Fellow of the Royal Society, and iMember of the Society of
Jlaiiquariei, in London.

I.nbsp;An Examination of Salts and Saline SuS^
JtameSyXktiT amazing Configurations and Cry fids,

ii.nbsp;An Account of various Animalcules
never before defcribed , and of many other

I S Grace the late Duke of
Montagu, (whofeName muft
be ever dear to all that knew him) was
pleafed to honour, with his particular
Notice, the Experiments and Obferva^
tionsdefcribedinthe following Sheets,
and frequently expreffed his Defire of
having them made public: and as your
Lordiliip feemed no lefs to admire
thefe wonderful Operations of Nature,
I take the Liberty to requeft your
Acceptance of a Work, whofe No-r
A 3nbsp;yelty

you, fome Entertainment, at the fame
Time it affords me the defirable Op-
portunity of profcfTmg my moft hum-
ble Refpe61.

covers in the Particles of Matter com-
pofing Salts and faline Subftances,
Properties whofe amazing Effeds
would furpafs all human Belief or
Conception, were we not convinced
of their Truth by the ftrongeft ocular
Demonftration. That beautiful Or-
der in which they arrange themfelves
and come together under the Eye,
after being feparated and fet at Li-
berty by Diffolution, is here defcrib-
ed and (hewn.——Did they amongft
them all compofe but one Kind of
Figure, however fimple, with Con-

DEDICATION. vii
dare it wonderful : What muft we
then fay, when we fee every Species
working as it were on a different
Plan, producing Cubes, Rhombs,
Pyramids, Pentagons, Hexagons, Oc-
tagons, or fome other curious Figures
peculiar to itfelf ; or compofing a
Variety of Ramifications, Lines, and
Angles, with a greater Mathematical
Exadnefs than the moil: fkilfui Hand
could draw them ?

Senfible of my own Ignorance, I
pretend not to account how this is
done : all I know is, that Chance or
Accident cannot pofTibly produce
Conftancy and Order, nor inert Mat-
ter give Adivity and Diredion to it-
felf. When therefore thefe Particles
of Salts are feen to move in Rank and
File, obedient to unalterable Laws,
and compofe regular and determined

viii DEDICATION.
Figures, we muft recur to that Al-
mighty Wifdom and Power which
planned out the Syftem of Nature,
direds the Courfes of the Heavens,
and governs the whole Univerfe.

The Experiments here defcribed,
and which the Reader is inftrucled to
make, muft I think generally enter-
tain ; but merely to entertain, is,
I hope, the Icaft of their Vforth.
They may poiTibly lead to the
Knowledge of what pafles in the
Formoticn of Gems, and the moft
beautiful mineral ProducStions: And
as every new Difcovery is an Encou-
ragement to farther Difquifition, the
Hints here given may perhaps fet abler
Heads at Work to improve Art on the
Principles of Nature. Examinations
by the Microlcope, in the Manner
here direded, may likewife be em-
ployed to afcertain the Truth and

DEDICATION. ix
Purity of many limple Subftances and
Coropofitions made ufe of in Medi^
cine, and deted Fraud and Impoli-r
tion.

The minute living Animals exhi-
bited in the Second Part of this Work,
will excite a confiderate Mind to ad-
inire in how fmall a Compafs Life
can be contained, what various Or-
gans it can aduate, and by what dif-
ferent Means it can fubfift. They
will alfo fhew that the Hand which
niade them is not confined to Size or
Form; and that it has not been
v/anting to beftow on Creatures al-
rnofl: invifible, and feemingly incon-
fiderable, every Member and Faculty
convenient to their Happinefs.—But
this is an endlefs Subjed, with which
I fliall detain you no longer, than to
pbferve, that were there wanting

x DEDICATION.
Proofs of a Deity, they might here
I think be found in great Abund-
ance.

Your Lordfhip's great Condefcen-
fion and Goodnefs, in honouring this
quot;Work and its Author with your Pa-
tronage, muft always be remembered
and acknowledged with the utmoft
Gratitude, by,

hoped the Book now publißed, will
be accepted favourably by the Curiousy and
particularly by thoje acquainted with the TJfes
of the Microfcope, as it opens to their View
an almoß inexhaußible Store of ObjeSis for that
Inßrument j and many who are Strangers to
it, may, 'tis likewife hoped, be excited by what
they read here, to lend fome Attention to fuch
of Nature s wonderful ProduBions as cannot
be known without it. The earnefl Wiß and
Beßre of the Author is, that all People would
fee with their own Eyes, and determine by their'
own Judgment 5 neither raßly dißelieving
•what is here related becaufe it may feem

furprizing, nor lazily giving it Credit on his
bare Word without maki'ng Experiments them.quot;
Jehes,.

As many of both Sexes, who have not had
the Advantage of a learned Education, are
notwithjlanding greatly defircus of Knowledge j
for the Sake offuch, this Treatife is written
in 'Terms mojl eafy to be underjlood-, and a
Jhort Account of the feveral Subftances here
examined is given for their Information.

Be legs Far don of the Phyficians and Che-
mifts, for encroaching now and then on their
Province, in the Courfe of the following Oh-
fervations and Remarks; and hopes they will
generoujly excufe any Miftakes he may have
fallen into, as he is neither Phyfician nor Che-
mift. 'Thofe too who are themfilves well ac-
quainted with the SubjeBs here defcribed, will
not, he hopes, he difpleafed at his endeavouring
to injlruB fuch as know them not.

He acknowledges his Obligations to many
ingenious Friends, wha have favoured him

fSe/r Obfervations from 'Time to Timet
Jeveral of which are irferted in this Worki
and Jhall always be thankful to any Gentle nan
who will fend him an Account of whatever be
thinks remarkable»

CHAP. I. Concerning the Configuration
and Cryftals of Salts and faline Sub-
ftances,nbsp;page I

Chap. VI. DireBions for making a Colledion
of the Solutions of Salts and faline Sub-
ftances, and preferving them always in
Readinefs to be examined by the Micro-
fcope,

Chap. VII. A general Explanation of the
Plates, with fome farther Thoughts on the
Cryftals and Configurations of Salt«, 37

Chap. :^III. White Vitriol,
Chap. XIV. Dijiilled Verdigreafe^
Chap. XV. Alumy
Chap. XVI. Borax,
Chap. XVII. Salt Ammoniac,
Chap. XVIII. m of Lead,
Chap. XIX. Salt of Tin,
Chap. XX. l^ns Veneris,
Chap. XXI. Flowers of Antimoyty,
Chap. XXII. Corrofive Sublimate, and Arfe-

125

138.

147

149

150

152

153
155

15S
160

162

163

Chap. XXV. Cheltenham Salt, ■
Chap. XXVI. Epfom Salt,
Chap. XXVII. Sal PolychreJImn,
Chap. XXVIIl. Glaubers Salt,
Chap. XXIX. Salt of Tartar,
Chap. XXX. Tartar Vitriolated,
Chap. XXXI. Flowers of Benjamin,
Chap. XXXII. Salt of Camomile,
Chap. XXXiil. Salt of Coral,
Chap XXXIV. Salt of Baum, or Balm, 165
^nbsp;'nbsp;Chap.

Chap. XXXVIIL Salt of Cucumber,nbsp;170
Chap. XXXIX , Salt of Peruvian Bark, 171
Ch?,p. XL. Salt of Liquorice,

CHAP. I. Of the Hair-like InfeBy p. 233
Chap. II. Of the Oat-Animal, 24.1
Chap. III. Eels in Pafte Viviparous, 244
Chap. IV. Eels in blighted Wheat,nbsp;250

Chap. VIL Different Kinds,, of Wheel Ani-
mals, :nbsp;292
Chap. VIiL Animalcules with Shells and
Wheels, ' 295
Chap. IX. 1'he Water Flea with branched
Horns, 302
Chap. X. T^he Bell-Flower Animal, or Plum-
ed Polype, 306.
Chap. XL he Satyr, 314
Ciiap. XII. Three Aquatic Aiiimals defcribed.

Chap. XIV. Eggs of the fnall Freß-Water
Snail, and Animalcules adhering to them, 324

Contents of the Chapters. x'lx
Chap. XVII, m FipeAnimah p. 349
Chap. XVIII. rheWatcrHog-Loufe,orSow,

Chap. XIX. Ofthe FreJh-Water Squillce, 3 56
Chap. XX. The brijiled InfeB,nbsp;363

Chap.. XXVII. A Letter from a Friend
containing many curious Microfcopical Ob-
f-rvations,nbsp;^go

^omj Account of a new conftruded Micro-
itope ujed tn the foregoing Experiments, 422

Remarks on a Micrometer to be applied to
Double Compound Microfcopss. By Mar-
tin Folkes, Efq-, F. R. S.nbsp;p. 426
A Defcription of Mr. Leeuwenhoek's Micro-
fcopes,quot; ' 434
Direólions for making the Reprefenfation or
fiSiure of any Medal or Coin, 436

I wifh nothing more heartily
te^ ^ ^han the real Advancement of ufe-
f^l Knowledge, by difcovering, as
far as poffible, the Operations of
i^ature in the Formation of Bodies, and
then- EfFeds on one another: and as the
reafonable Way of accounting for
their Eixedts muft arife from a Difcovery
and Con f,deration of the Figure, Size,
ijohdity. Weight, and Motion, of their
vol. ii.nbsp;b

conftituent Parts ; fince we do not, I think,
fuppofe Body to adl on Body by any other
Principles*: I have long imagined, that
if by an eafy and natural Separation of
fuch their conftituent Parts, it were poffible
to know the comparative Size and Figure,
■Solidity and Motion of the Particles com-
pounding Bodies, when fo feparated from
one another ; and if we could alfo learn in
what Order and Figure they naturally come
together, and re-unite after fuch a Separa-
tion, it might lay a Foundation whereon
fome able Builder, may ereft a valuable
Superftructure.

With this View I have been making Ex-
periments, almoft continually, for above
ten Years paft, on a great Variety of Sa-
line Bodies, Mineral, Vegetable and Ani-
mal, as well as many other Subftances,
both fimple and compound, whofe Parts
can be diffolved in Fluids, after a Method
which has never hitherto been defcribed by
any Author, or praftifed before myfelf by
any body that I have heard of. And tho'
I have found their original Particles undifco-
verable by any Microfcope, the Time I hope
has not been wholly mifemployed; fince
I have been enabled, by the Help of that
Inftrument, to behold the amazing Order

^ * Unlefs the new-difcovered Properties of Ekaricity be
jmagined owing to fome Caufes we are ncy yet acquainted

and Regularity, wherewith, after being fe-
parated by Diffolution, they come together
and^ re-unite under the Eye, when put in
Adtion by certain Degrees of Heat, in Con-
figurations iappropriated to each of them
refpeftively, and w ith a Conftancy that is
furprifing.

That particular Notice, wherewith the
Royal Society was pleafed to honour
thofe Experiments -f, encouraged me to
profecute them with all the Care in my
Power, to minute down every remarkable
Cucumftance in the Procefs, and to make
faithful Drawings of each Configuration.

Much has been already publiOied by fe-
veral curious Obfervers concerning the Cryf-
talizations and regular Figures of Salts,
and none I hope will imagine I am hereby
^deavouring to deprive them either of their
Difcoveries or their due Praife. But I pre-

fume my Experiments go a great deal far-
ther, both as to the Manner of Examina-
tion, and the Variety of Subjeds examined :
for by the Affiftance of Heat, which in a
greater or lefs Degree is perhaps a conftant
Agent in all the Operations of Nature,,
very different Configurations and Effefts are
produced than what can be caufed without
it, and our Information is thereby rendered
much more compleat and perfed:.

To give one iingle Inftance of this, which
takes place equally in moft other Subjedts:
The Cryftals of Alum are well known, and
their Figures (when a Solution of it is per-
mitted to cryftalize quietly and of itfelf)
have been truely defcribed and pictured bv
others to be odaedra, confifling of hexangu-
lar, triangular, and quadrangular Planes :
but nobody I believe has before difcover'd,
at leaft nobody hitherto has informed the
World, that the Particles of Alum, when
feparated by Dilfolution, and excited to
Adion by a certain' Degree of Heat, fo.
arrange themfelves as to compofe regular
and delightful Star-like Figures of different
Sizes, many whereof have long ftreaming
Tails, and refemble Comets: that it fhoota
forth in fome Places Figures like.Palifadoes,
and in others an almoft infinite Number
of parallel Lines, moft exquifitely ftrait,
i^xaft aiid fine; fome crofiing others at
right Angles, and compofing an Appearance
1nbsp;beyond

beyond Defcription beautiful. Vide Plate III.
No. I. Indeed the Produftion of the Star-
like Figures depends on a certain Nicety irt
the Heat continued for a certain Time,
which one is not always fure to hit precife-
ly 5 and therefore, though they appear very
frequently, they are not quite fo conftant
in every Trial as its other Configurations;
but I doubt not Praftice and Obfervation
will render them fo in Time.

I muft beg leave to call thefe Arrange-
ments of the Particles by the Name of
Configurations, thereby to diftinguifh them
from the Cryftalizations mentioned by
others, whereto they bear little or no Re-
temblance. Cryftalizations feem produced
by a Tendency or Attradtion of the Saline
Particles towards certain Points, about which
they combine in regular and determin'd
Forms, according to their refpeftive Kinds,
Configurations owe their Shapes m.oft pro-
bably to different Fits of Repulfion and
Attradion, (thofe two wonderfuF Princi-
ples which occafion moft of the Changes
in Nature) taking place at certain Intervals
and 111 certain Proportions, and operating
according to Rules that are conftant and
uniform, though little known to us at
prefent. Or if, to make the Subjed un-
derftood the better, I may be permitted
to fetch a Comparifon from a common
Suppohtion, without examining whether it
B 3nbsp;bs

be true or falfe, Cryftalization is like the
retiring of the Sap into the Roots of Trees
at the Approach of Winter, where during
the cold Seafon it remains dormant and
unadive : Configuration refembles what re-
fults from the Expanfion of the fame Sap
at the Return of Spring, when excited to
Adion by theSun's genial Warmth, itpuihes
every Way, exerts its vegetative Force,
and becomes produdive of Bads, Leaves,
Branches, Bloffoms and Fruits. But the
Drawings of one and the other compared
together and confidered, will render this
Difference more intelligible than all the
Words in Language.

The beautiful Regularity and Order al-
ways obfervabie in the Works of Nature,
are no where more evident than in the
Experiments I am mentioning; where the
invifible Particles of Matter, though difu-
nited by a Menftruum, and removed to Dif-
tances from each other, are no fooner ex-
cited to Adion than they mutually affift
one another to compofe Figures peculiar
to their feveral Kinds, with as much Cer-
tainty and Uniformity as Seeds of the fame
Plant produce Plants like one another, not
indeed precifely as to the Number or Po-
rtion of their Branches, Leaves or Flowers,
but in the general Growth and Fafhion,
and thofé other Particularities whereby each
Species is diftinguilhed.

Our Eyes are continually accuftomed to
fee the Productions of Nature when finifli-
ed, or brought a conliderable Way to-
wards it J and what contemplative Man
can behold them without Admiration and
Delight! but in thefe Experiments we are
enabled, by the Affiftance of Glafles, to view
her adlually at Work, forming under our
Eyes, and in a few Minutes, Bodies fo ex-
quifitely beautiful that nothing but feeing
can give any juft Idea of them; and that
too with fuch a Variety, as to the Plan
and Fafhion of each Kind, as is abfolutely
unconceivable.

Defcriptions of the Subjefts here treated
of would be unintelligible without the Af-
fiftance of Drawings. Drawings therefore
have been made, and Copper Plates en-
graven, at no fmall Expence, of the diffe-
rent Configurations hereafter mentioned:
which, though greatly deficient in Beauty
and Regularity, if compared with the Ori-
ginals, and only pretending to give fuch a ge-
neral Refemblance as may.diftinguifli each
Kind from other, will 'tis hoped prove fa-
tisfadory to thofe who lhall pleale to re-
peat the Experiments after me : for how-
ever ftrange they may appear, they are
no fanciful Reprefentations produced by the
Strength of Imagination, nor are they
taken haftily from one or two Trials, but
truely fhew what generally prefented in
B 4nbsp;great

great Numbers of repeated Obfervations.
Their Figures are indeed fo extraordinary,
that I fliould not dare to have laid them
before any body, much lefs to have pub-
lifiied them, vi^ere there not many Gen-
tlemen of unexceptionable Credit who are
living Witneffes of their Truth, and was I
not alfo able, almofl at any Time, to pro-
duce Configurations like thofe they were
taken from.

Thefe conftant and regular Workings of
Nature, which the Microfcope difcovers,
may poffibly condu6t us a Step farther in-
to her Receffes, and affifh us to judge of
Caufes and EfFedls in many Cafes where
at prefent we are greatly at a Lofs, iince
acjcofding to Dr. V/oodward-]-, quot; the Stea-
dinefs and Conftancy of Nature in all its
Produitions, and in the Formation of all
Bodies, happens from the Conftancyof the
quot; Procedure of the Agents that are inftru-
mental to the Formation of thofe Bodies,
and from the Unalterablenefs of the Cor-
quot; pufcles which ferve for conftituting and
compofing of thofe Bodies.quot; And we are
told by the Rt. Rev. Author of SyrisX,
that the '' Analogy, Conftancy and Uni-
quot; formity in the Phaenomena or Appear-
ances of Nature are a Foundation for gene-
ral Rules : and thefe are a Grammar for
if' the Underftanding of Nature, or the Series

quot; of Effefts in the vifible World, whereby
quot; we are enabled to forefee what will come
quot; to pafs in the natural Courfe of Things.quot;

As there is good Reafon therefore to
expeft, that the following Experiments
may conduce fomething towards account-
ing for many Caufes and EfFedts in Nature,
when duly confidered by People of true
Judgment, to fuch I freely fubmit them;
without pretending any thing more my-
felf than barely to relate Fads : but fhould
they ferve no other Purpofe than to pre-
fent a new Set of Objeds for the Micro-
fcope, full as wonderful and. entertaining as
any that have ever been yet examined,
affording by Mixture a Variety almofl in-
finite, eafily procured, and always ready for
Obfervation, there are many I flatter myfelf
to whom they will prove acceptable. And
I fhall endeavour to afiift as much as pof-,
fible the Curiofity of thofe who may be
inclined to repeat thefe Experiments after
me, by defcribing in the plainefl Terms
each Circumftance neceffary to be known,
either previous to, or during the Time of
Obfervation by the Microfcope, and dare
aflure them for their Encouragement, that
the Trouble is very little, though the Plea-
fure and Information refulting therefrom is
great.

The Method of preparing Salts and Saline
Substances, /ôr the viewing their Con-
figurations.

Diffolve the Subjed to be examined in no
krger a Qiiantity of River or Rain Water
than I am certain it is fufficient to faturate.
If it is a Body eafilydiffolvable I make ufe of
cold Water, otherwife I make the Water
warm, or hot, or even boiling, according
as I find it necefiary. After it is perfectly
diffolved, I let it reft for fome Hours, till, if
overcharged, the redundant Saline Particles
may be precipitated, and fettle at the Bottom,
or fhoot into Cryftals ; by which Means I
am moft likely to have a Solution of the
fame Strength at one Time as at another j
that is, a Solution fully charged with as
much as it can hold up, and no more; and
by thefe Precautions the Configurations
appear alike, how often fo ever tried:
whereas if the Water be lefs faturated, the
Proportions at different Times will be fub-
jedt to more Uncertainty ,• and if it be exa-
mined before fuch Separation and Precipita-
tion of the redundant Salts, little more will
be feen than a confufed Mafs of Cryftals.

The Solution being thus prepared, I take
up a Drop of it with a Goofe Quill, cut in

Fafliion of a Scoop, and place it on a flat Slip
of Glafs of about three Quarters of an Inch
in Width, and between three and four Inches
long, fpreading it on the Glafs with the
Quill, in either a round or oval Figure, till
it appears a Quarter of an Inch or more in
Diameter, and fo fliallow as to rife very
little above the Surface of the Glafs, When
it is fo difpofed, I hold it as level as I can
over the clear Part of a Fire that is not too
fierce, or over the Flame of a Candle at a
Diftance proportionable to the Degree of
Heat it requires, (which Experience only
can diredl,) and watch it very carefully, till
I difcover the Saline Particles beginning to
gather and look white, or of fome other Co-
lour, at the Extremities of the Edges. Then
(having adjufted the Microfcope beforehand
for its Reception, armed with the fourth
Glafs, which is the fitted for moft of thefe
Experiments,) I place it under my Eye, and
bring it exailly to the Focus of the Magni-
fier, and after running over the whole Drop',
I fix my Attention on that Side where I
obierve any Increafe or pufhing forwards of
cryftaUne Matter from the Circumference
towards the Center.

_ This Motion is extremely flow at the Be-
ginning, unlefs the Drop has been overheat-
ed, but quickens as the Water evaporates,
and m many Kinds towards the Conclufion
produces Configurations with a Swiftncfs

iinconceiveable, compofed of an Infinity of
Parts, which are adjufted to each other with
an Elegance, Regularity and Order, beyond
what the exafteft Pencil in the World,
guided by the Ruler and Compaffes, can ever
equal, or the mofl luxuriant Imagination
fancy.

When Aftion once begins, the Eye can-
not be taken off, even for a Moment, with-
out lofing fomething worth Obfervation :
for the Figures alter every Inftant till the
whole Procefs is over and in many Sorts,
after all feems at an End, new Forms arife,
different entirely from.any that appeared be-
fore, and which probably are owing to fome
fmall Quantity of Salt of another Kind,
which the other feparates from and leaves
to aft after itfelf has done : and in fome
Subjedts three or four different Sorts are ob-
fervable, few or none being fimple and ho-
mogeneous.

When the Configurations are fully form-
td, and all the Water evaporated, moft Kinds
of them are foon deftroyed again by the
Moifture or Action of the Air upon them ;
their Points and Angles lofe their Sharpnefs,
become uneven and defaced, and moulder
as it were away. But fome few are perma-
nent, and by being inclofed between Glaffes,
as I lhall dired hereafter, may be preferved
Months, or even Years, entertaining Objeas
for the Microfcope.

■A/quot;. It happens oftentimes that a Drop
of a Saline Solution can hardly be fpread on
the Slip of Glafs, by reafon of the Glafs's
Smoothnefs, but breaks into little Globules,
as it would do were the Surface greafy;
this was very troublefome, till I found a Way
of preventing it, by rubbing the broken Drop
with my Finger over the Glafs, fo as to leave
the Glafs fmear'd with it; on which fmear'd
Place when dry, another Drop of the Solu-
tion may be fpread very ealily in what Form
one pleafes.

It likewife fometimes happens, that when
a heated Drop is placed properly enough for
Examination, the Obferver finds he can dif-
tinguifh nothing: which is owing to Sa-
line Steams that rife from the Drop, cover
and obfcure the Objeit Glafs, and therefore
muft immediately be wiped away with a foft
Cloth or Leather.

'Tis I think an allowed Maxim, that Salts
aft not unlefs in a State of Diffolution, for
which Reafon I diffolved them in order to
obferve their Manner of ading. A certain
Degree of Heat is likewife moil commonly
employ'd by Nature in all her various Pro-
ductions : wherefore I imagined that by
^e Affiftance of Heat, applied in different
Degrees, I might in fome Sort imitate Na-
ture, and produce fuch Figures as Salts are
thrown into, not when they ceafe to aft,
which I apprehend is the Cafe when they

are formed into Cryftals, but evenwhilfl they
are ading : and this what I call their Con-
figuration does moft wonderfully fliew.

My Intention was to difcover as far as
might be, the natural Inclination, Progref-
fion and Figure of each refpeclive Salt under
Examination it was confequently necelTary
to avoid making ufe of any Diflblvent, which
by containing other Salts might create Con-
fufion, and produce Forms not conftant or
effential to the Subjed of Inquiry. River or
Rain Water has therefore moft common-
ly been my Diflblvent, being what I judged
leaft likely to prejudice my Experiments.
I am very fenfible neither Salts or other
Bodies are to be obtained unmixt and per-
fedly homogeneous : but I have taken Pains
to procure fuch of each Kind, as appeared
moft pure and perfe6l, I mean of the Am-
ple Salts J as for the Compounds I was
obliged to rely on the Chemift.

In all Examinations by the Microfcope
of Saline Solutions, even though made in
the Day-time, I always employ the Light
of a Candle, and advife every Obferver to
do fo likewife : for the Configurations be-
ing exceedingly tranfparent, are rendered
much more diftinguifhable by the brov/n
Light a Candle affords, than by the more
white and tranfparent Day-light; and be-
fides, either by moving the Candle or turn-
ing the Microfcope, fuch Light may be

It may be alfo proper to take Notice,
that no Kinds of Microfcope are fit for thefe
Obfervations, but fuch as have an open
Stage, whereon the Slips of Glafs with the
Liquor upon them may be placed readily,
and in a perfed horizontal Pofition and
moreover where they can be turned about
freely, and without difordering the Fluid.
Thofe Microfcopes where Sliders or Slips
of Glafs are thruft in between two Plates,
as in Wilfon\, See. be they in v/hatever Di-
reftion, cannot therefore properly be em-
ployed here.—The following 'Obfervations
were all made by a double Microfcope,
conftruded by Mr. Ctif, in Flcet-Jireet,
with fome Regard to thefe Experiments!
Its Figure refembles what is called com-
monly the Double ReflcBing Microfcope, and
like that it receives Light from a Speculum
underneath: but befides an Improvement
in the Pofition of the GlalTes, its Stage is
difencumbered with Legs, and quite open
for the Reception of Objeds without Trou-
pe ; Its Motion is not by Jerks, as in the
Microfcope juft now mentioned, but re-
gulated by a fine-threaded Skrew, whereby
^ IS adjufted to the Eye with great Eafe and
l^xadnefs j and all that try it will I believe
judge It not only the moft convenient Micro-
scope for this Purpofe, but likewife for gene-
• 9nbsp;^ ral

ral Ufe. Wherefore as this Inllrument, which
has been conftrudted fmce the Publica-
tion of the Microfcope made eajy, could not
be given there amongft the other Micro-
fcopes then in ufe, I intend at the End of
this Treatife to infert a Drawing and fhort
Defcription of it.

IT feems neceffary, in order to make-
the Matter in Hand underftood the bet-
ter, that fome Account be given of what is
meant by Salts and Saline Subjlances, toge-
ther with fome fhort Explanation of the
DifTolution of fuch Subftances, and their
Cryftalization afterwards j whereby the Dif-
ference between my Experiments and thofe
of others may become more evident.

Few will I prefume imagine, that I mean
by Salts fuch Subflances only as afford what
is called a Salt Tafte for Salts are of all
T-afles, and Sugar itfelf is no other than
a Salt extrafted from the Sugar Cane. But
Vve underftand by Salts, all Subftances what-
foever that are diffolvable in Water, or
whofe Parts become fo feparated thereby
as to difappear tlwrein j which, notwith-

ftanding the Water being evaporated, fheu'
themfelves again combined in fome fort of
angular Forms, v(?itb a Degree of Tranfpa-
rency, and to the Talle are more or lefs
pungent. To this may be added, that they
are fufible by Fire. .

. Salt, thus underflood, is one of the firll:
Principles of the Chemifts; and indeed has
good Reafon to be efteemed fo, as it en-
ters into the Compofition of all Bodies. It
is every v/here, and in every thing : for if
any Stone^ Plant, or Anim.al be burnt, a Salt
remains in the Arties, which tray be ex-
trafted by Water, and feparated from the
Caput Mortuum.

It is the Nutriment of Ariimals, Vege-
tables and Minerals, infomuch that Herbs,
Roots, Bread, amp;c. deprived of their Salts,
can neither fuflain, nourifh, or increale the
Bodies of Animals j and the Earth when di-
verted of it becomes abfolutely barren.
_ Vegetables and Animalsgt; whilfl: flourifh-
ing and alive, difcharge by Perfpiration and
other more fenfible Evacuations, the Excefs
and Excrements only of the halts whereby
they are preferved; but when they perifh,
the Chain whereby the Parts were kept to-
gether becomes broken, the Salts regain
their Liberty by Putrefaftion, fome fly
away into the Air, and the reft remain in
a Condition to enrich and render fertile

Taftes, Smells, and moft: other Effeds
of Bodies on one anoiher, feem occaiioned
by the Action of Salts, which by flriking
on our Organs produce SenfatioTts corre-
fpondent to their Figures, and by the fame
means afte£l all other Bodies.

Being tranfparent, and having a ftrong
attradive Power, they probably fupply both
Matter, ConfiHience and Form to Spars, Cry-
ftals, Diamonds,, and all other Gems and pel-
lucid angularly figured FofTils. When com-
bined and at Reft they are perhaps the Balis
of Cohefion and Solidity in moft Bodies,
the Pegs or Nails that hold the Parts of
other Matter together; but when put in-
to Motion by the Separation of their com-
ponent Particles, and their repulfive Force
(which is no lefs vigorous than their attrac-
tive Power) becomes exerted, they are the
moft adive Principles in Nature, like Knives
or Lancets .cut their Way through every
thing, and produce the moft furprizing
Changes. Whence the Chemifts. fay, that
in the Sun and in Sal fare all Nature's Pro-
duftions; and, that he who knows not Salts,
will never perform any thing in Art.

The Diftincftion of Salts into acid and
alkaline, into volatile, fixt, and eflential, I
fliall leave the Reader to confult chemical
Writers about.

H E Diffolution of Salts or falirte Bo-
dies is effeded by an Intrufion or In-
terpofition of the Particles of Water, or
fome other Diffolvent, between the Particles
that compound fuch Bodies; whereby their
Combination is deftroyed, and they become
feparated from each other.

Sir Ifaac Newton -f- accounts for the Diflb-
lution of fuch Subftances from the great
Principle of Attradlion, and the Manner
thereof is explained by Tgt;v. Friend, in his
PrceleBiones Ghemica, p. 6r, where he gives
a mechanical Defcription of the diffolving
of common Salt in Water 5 the meaning
of which in few Words is, quot; that the Cor-
pufcles of Salt being extremely fimple,
minute, and folid for their Bulk, are con-
fequently endued with a ftrong attradive
Power: (Attradion being,cceterisparibusy
always in proportion to the Quantity of
Matter:) the Particles of Water are there-
fore attraded more, vigoroufly by the fa-
line Particles than by one anotherfor the
watery Particles cohering but flightly,and
moving readily, when they approach the
Particles of Salt, rufh as it were into their

Pores, which are very numerous, the Tex-
** ture and Cohefion of their Parts become
** intirely broken and deftroyed, the Corpuf-
quot; cles are feparated, and float here and there
quot; in the Water.quot;

Water (or fome other Liquor) having
thus infinuated between the component
Particles of faline Bodies, defliroyed their
Cohefion, and removed them from each
other; if the minute difunited Particles are
fewer than what the Interftices of the Water
can contain, they remain fufpended in the
Fluid, though being extremely fmall and
tranfparent the Eye cannot difcern them ; for
notwithftanding Salts are fpecifically heavier
than Water, their minute Particles, when
feparated, having their Surfaces increafed
in proportion as their Bulk is diminifhcd,
are unable to overcome the Refiftance of
the Fluid, and confequently cannot flnk
therein. But if the faline Particles are
more in Quantity than the Interftices of
the Water can eafily contain, the Refidue
attract each other, form little Maflquot;es hea-
vier than the Fluid, and either fall to the
Bottom, or adhere to the Sides of the Veflquot;el,
and that moft commonly in the Form of
regular Cryftals.

' I ^ H E ufual Way of procuring Cryflals
_ X from any Salt or faline Subftance
is, to diflblve the fame in warm Water j to
filter the Mixture if there be any Foulnefs;
to evaporate till a Film is feen at Top j
and then to fet it in a cool place to flioot.
Heat enables the Water to diflblve and hold
up a greater Quantity of the Salt than it
Would do without it, and Cold afterwards
greatly affifts its forming into Cryftals.

The Cryftals thus formed, whether more
or lefs in Quantity, will always have fuch
Figure as is peculiar and conftant to the
Kind of Salt they are procured from; and
how often foever their Particles be fepa-
rated by Solution, they will come together
again, and reunite in fuch a Manner as to
gt;roduce Bodies exaftly of the fame regu-
ar Forms; which muft imply, that fuch
component Particles, whatever their Shape
or Texture be, are themfelves unalterable,
and that the Principle or Law whereby
they are brought together is uniform and
perpetual. Their Concretion may be ac-
counted for on Sir Ifaac Newton s Princi-.
pies, by the attraftive Force with which
all Bodies, and Salts more efpecially, by
reafon of their Solidity, arc endued ; where-,
by, when the Water wherein they float
C 3nbsp;is

is evaporated to fuch a Degree that the
faiine Particles come within the Reach of
each ether's attradive Power, and do ac-
tually attradl one another more vigoroufly
than the Fluid attradls them, they form
themfelves into Cryftals. And as to the
Regularity of their Figures, quot; that argues
(according to the fame great Man) that
the Particles of the Salt before they con-
quot; creted, floated in the Liquor at equal
quot; Diftances in Rank and File; and by
confequence that they a6ted upon one
'' another by fome Power which at equa
Diftances is equal, at unequal Diftan-
quot; ces unequal. For by fuch a Power they
quot; will range themfelves uniformly, and
quot; without it they float irregularly, and
come together as irregularly.quot; He alfo
fuppofes, quot; that the Particles not only
range themfelves in Rank and File for
concreting in regular Figures, but alfo by
fome kind of polar Virtue turn their ho^
m-ogeneal Sides the fame Way
As that Conftancy of Figure, obfervable
in the Produftion of Cryftals from the
fame Salt, proves their component Particles
to have fome determined and unalterable
Shape, fo the Difference of Figure pecu-
liar to the Cryftals of different Salts, in-
duces one to believe, that the com
Particles of each Kind differ no

Siiape from the Particles of every other Kind
than the Cryftals they compofe do.

The Particles of them all are indeed fo
exquifitely minute, that no human Eye or
Inftrument can poftibly difcern them, be-
ing finer, in feveral Kinds, even than the
Particles of Air, forcing their Way through
Metals, Glafs, and other Bodies, where
the Air can find no Entrance. Conjeftures
have notwithftanding been made concern-
ing their Figures ; fome fuppofing them
exaftly of the fame Shape in little, as the
Cryftals they conftitute by their Combi-
nation are in a larger Size; whilft others
infift, that their Shape is intirely different
from what appears in the Cryftals ; the
Figures whereof arifs, as they imagine,
from a ftronger Attraction on fome Sides
of the fame Particles than on others,
whereby the Concretions on thofe more
attractive 'Sides are greater : for, fay they,
if the Particles of Salt that fwim in a Fluid
attrad each other mutually, and by their
Figure have a greater attradive Power
in fome Parts than in others, and if their
Contad be greateft in thofe' Parts, fuch
Particles will form themfelves into Bodifes
wuh given Figures, or, in other Words,
Will conftitute regular Cryftals.

24 Component Particlu of Salts.
Giilielminus obferves, that the fenfible Cryf-
tals of any Salt, however large or minute
they may be, have always the fame Fi-
gures ; the Co-ordination of the Parts not
depending on the Quantity of the com-
ponent R^atter: that Nitre, for Example,
in its Efflorefcences from Walls, difpofes
itfelf into very llender Bodies of the like
Figure exadly as its larger Cryftals; and
that not only Cryftals too fmall for our Eves
to fee, but even the minuteft, Particles'of
their Salt, that were diflblved in the Water
before their Cryftalization, have the fame
Figure as the larger Cryftals have. Whence
he fuppofes the firft Principles of Matter
whereof the Salt is compofed, and which
on Account of their Srnallnefs no Force
can polfibly divide, to have fuch deter-
mined Figures, a^ they can never change,
impofed on {hem at their Creation. And
for this he quotes Mr. Leewwenhoek, who
aflerts, that if) Solutions of Cyprian Vitriol,
and Qf Tartar, he has feen Particles, which
tliough not larger than the twenty thou-
sandth Part of the'Thicknefs of a Hair,
were exactly figifred like their larger Cry-
ftals ; and ^hofe Figures in two or three
Minutes increafed to an hundred times their
former Bulk, ftill retaining their Figurp,
however they were enlarged in Length and
Preadth.nbsp;■ . o

Component Particles of Salts. aif
for the Separation of a Salt from the Fluid
wherein it is diffolved, but an Inclination
of the Planes of the fmalleft Particles to
unite ; which Inclination being alike in all,
they join one after another on every Side:
by which means the Size grows larger, but
the Figure alters not. Thofe in common
Salt he affirms to be minute Cubes, in
Vitriol Parallelopipeds, and in Nitre hexa-
gonal Prifms.

Hence he infers, that the Figures of the
Cryftals prove not only the Exiftence and
Shape of their component Particles, but
withal demonftrate that the Cryftals are
themfelves produced by an appofite Union
of fuch-like figur'd Particles, whofe Figures
cannot be deftroyed unlefs by Annihilation.

That the moft minute Cryftals difcerni-
ble by the Microfcope maybe obferved grow-
ing under the Eye, and enlarging their Di-
menfions many thoufands of times without
an Alteration in Figure, I dare affirm from
my own Experience: but I pretend not
thereby to determine the real Shape of the
original Particles of any Salt, or to under-
ftand the other Properties concerned in their
Combination. After all my Experiments, I
am too fenfible of my own Ignorance to fet
up any Hypothefis : that I leave to abler
Judges, on future Trials ; begging Leave
inftead thereof to fubmit the following
Queries to be confidered at Leifure.

O not Attradion and R.epuirion feem
to be the principal adtive Powers
whereby the natural Changes in bodies are
produced ?

Are not thefe Powers inherent, proba-
bly, in all Matter, however their Agency
may be fufpended, diminiihed, augmented,
or otherwife diverfified ?

May we not fuopofe, that by the. firft
of thefe Powers the original Particles of
Matter be brought together and conjoined,
in the Formation of nioft compounded Bo«
dies ? and does not the Deilrudtion of fuch
Bodies, or the Separation of their compo-
nent Particles, feern probably greatly owing
to the latter ?

Is there not Reafon to believe, that the
Particles of Matter conftituting Gold, Stone,
Wood, Flefh, amp;c. are difterent from each
other ab Originej and, confequently, that
there are different Kinds of fimple material
Particles ?

quot;Muft not thefe Particles (however un-
conceivable their Minutenefs be) have fome
determined Figures and Sizes ? May not
fuch Figures and Sizes be different, and
endued with different Degrees of the at-
tractive or repulfive Force ? and may not
the Difference in Bodies as to Coherence,
-. . 6nbsp;Soli-

Solidity, Duration, amp;c. be owing to the
various Intermixture and quot;Combination of
Particles either alike, or unlike in Size and
Figure f ?

May there not be a Kind of Polarity in
the original Particles ? or, may they not
attradl at fome Points and repel at others,
and that in various Proportions, according
to their Inclination towards each other, their
Diftances, their Points of Contadt, or other
Circumftances ? May not fuch Attraction
or Repulfion be excited, or fufpended, by
Heat, Cold, Motion, Reft,nbsp;And as

Light has alternate Fits of eafy Reflexion
and eafy TranfmifTion J,, occafioned by the
different original Properties of the different
Sides of its Rays (as Sir Ifaac Newton

quot; All the Phaenomena in Nature are produced by
Motion. There appears an uniform working in Thing»
great and fmall by attraSing and repelling Forces. But the
particular Laws of Attraaion and Repulfion are various.
The minute Corpufcles are impelled and direfted, that is
^ fay, moved to and from each other, according to various
Rules or Laws of Motion. Some Bodies approach together,
fly afunder. and perhaps fome others do neither.
fYnbsp;«'f^w'««. it is vifible

that the Particles of Water floating in the Air are moved
towards the Particles of Salt, and joined with them. And
When we behold vulgar Salt not to flow fer deliquium,
»quot;y we not conclude that the fame Law of Nature and
Motion doth net obtain between its Particles and thofe
p; floating Vapours ? A Drop of Water affumes a round
^gure, becaufe its Parts are moved towards each other :
Dut the particles of Oil and Vinegar have no fuch Difpofition
te.nbsp;ofCLOYNE's Syris, Page 11 o.

has fhewn) ; may there not alfo be alter-
nate Fits of eafy Attraction and eafy Re-
pulfion, occafioned by the Conjundtion, or
Oppofition of the attractive or repulfivc
Sides in the Particles of Matter ? May not
the Succeffion of fuch Fits be extremely-
quick, as in the Vibration of Bodies, amp;c. ?
and may they not be prevented, diminifli-
ed, circumfcribed, augmented, propagated,
or communicated with almoft infinite Va-
riety (as to the Modification) according to
the Conftitution of the Bodies wherein they
are excited, and the Aptnefs or Unaptnefs of
other Bodies near them ?

May we fuppofe the Attraction and Rc-
pulfion of Magnetifm, Gravity, and Elec-
tricity, to be different Powers, or different
Modifications only of the general attractive
and repulfive Powçr fuppofed refident in all
Matter

Do not Heat and Motion feem moft likely
to excite Repulfion ; and are not Cold and
Reft moft favourable to Attraction ?

V/hen the Particles of Subftances eva-
porate, become volatile, or fly away, is not
! uch Volatility pvving to the repulfive Force
of the Particles, fomehow or other put into
Action ? And is not the Explofion of Gun-
powder, amp;c. occafioned probably by a Fit
of Repulfion, excited fuddenly and violently
by Fire, in the component Particles of the
Gunpowder ?

Suppofing that Salts are diffolved, or their
Parts feparated, (according to Sir Ifaac
Newton^ Theory, and the beforemen-
tioned Explanation of Dr. Friend,) becaufe
the Particles of Water are more ftrongly
attradted by the Particles of Salt than by
one another, and rufh between and dis-
unite the faline Particles : may not the re-
pulfive Power of the faline Particles, as to
one another, be exerted at the fame Time ?
or may not a Fit of Repulfion inftantly fuc-
ceed the former Fit of Attraftion * ? And,
if the repulfive Power be of equal Force
in each of the Particles, will they not be
repelled to equal Diftances from each other,
and confequently be difpofed in Rank and
File : and when their next Fit of Attrac-
tion takes place, will they not unite accord-
ing to their Arrangement, and conftitutc
regular Figures ?

Without fuppofing fuch Fits of Repul-
fion and Attradlion, will it not be very
difficult to conceive, how the Particles of
Salt, which, notwithftanding their mutual
Attradion and Contaél, became feparated
each from other by their flronger Attrac-

quot; Unlefs by fome fuch means, it is not eafy to imagine
that the Particles of Water Ihould be able to enter the
interftices between the conflitoent Particles of Salts : for the
fnbsp;be fmaller even than thofe

bodies, which Air cannot pafs through, and confequently
thcu- Interftices muft be ftill much fmaller.

tion of the Particles of Water, ihould after-
wards, when carried to Diftances from each
other, where their mutual Attraction muft
be rendered much weaker, forfake the Par-
ticles of Water (which they had attraded
and joined themfelves to fo ftrongly) come
together again, and combine more firmly
than they did before * j for Cryftals are not
near fo eafy to diflblve as Salts before they
are cryftalized ?nbsp;ƒ

Does not the Power of Attraction in-^
creafe as the Diftances between the Par^-'
tides decreafe ? Is it not of great Strength,
when they are brought in Con tad ? and
would not moft Bodies be abfolutely folid,
and their Parts almoft infeparable, was not
Hardnefs an efi^ential Property in Matter,
which (by rendering the Particles incom-
preffible) prevents their Contad otherwife
than in Points, and occafions numberleis
Pores or Interftices between them ?

. May not the attradive and repulfive
Power be in proportion to the Surface rather
than the Solidity, (as it is found in Mag-
nets) ; andinconfequence thereof, are not the
fmalleft Particles endued with the ftrongeft
Attradion and Repulfion?

* When a Glafs Tube, made eleftrical by rubbing, at-
trafts a downy Feather, foon afterwards repels it, and drives
it continually away until the Feather has touched fome
other Body; after which it immediately attrafts, and then
repels it; have v/s not a plain ocular Demonllration of al-
ternate Fits of Attradlion and Repulfion

If the Particles of Matter have Sides and
Angles, will they not touch in more Points,
and form Bodies more folid and durabls
when joined together laterally, than when
connected by their Angles ? And if the
Surfaces of fuch Bodies are fmooth and
polifhed, will not their'Junction be much
the firmer ?

When one Salt is faid to be converted
into another, or appears in the Figures of
another, by the Addition of fomething
thereto; may it not be fuppofed, that by
the Intervention of other amp;aped Particles,
the Particles of the firft Salt are prevented
from cohering by the -.fome Sides and An-
gles as they did before j and that by the
Mixture of thefe Figures the new Forms
are produced Some Solutions will mix
and form Cryftals and Configurations by
Combination : in others, however blend-
ed, the Cryftals of each Kind appear al-
ways feparate.

^ Are not tranfparent Bodies compofed pro-
bably of homogeneous Particles, or Parti-
cles of the like Size and Figure, arrang-
ed in fome uniform Direction, whereby
their Interftices being rendered regular, are
ntly adapted for tranfmitting the Rays of
t'Jght ? And is not the Tranfparency of all
laiine Cryftals and Configurations moftlikelv
to be. owing to the fame Caufe I

Do not the Colours of Bodies alfo depend
on the Arrangement of their Particles, for
the more or lefs ready Reflexion, Refrac-
tion, Tranfmiflion, or Retention of the
Rays of Light ?

DireSiions for making a ColleBion of the Boluquot;
tions o/'Salts ^/z^/Saline Substances,
and preferving them always in Readinefs to
be examined by the Microfcope,

AS the Curious may be defirous to
colleft and keep by them the feveral
Sorts of Salts mentioned in this Treatife,
whereby they may at any time amufe them-
felves or entertain their Friends at a Mo-
ment's Notice ; I fhall put them in a Way
that will entirely anfwcr this Purpofe, foun-
ded on my own Experience.

Let a Drawer or Box be made three
Inches in Depth, ten Inches wide, a;nd
fourteen Inches long in the Clear : at about
an Inch and a quarter from its Bottom
place a thin Board of the exad Length and
Width of your Drawer, horizontally, on
four little Pillars faflened in the Corners ;
this Board having firfl of all round Holes
cut through it, in Rows, of a Size to re-
ceive Glafs Phials that hold one Quarter

of an Ounce, and fufficiently large for them
to go eafily in and out. Such a Board will
conveniently admit of twelve Rows, each
Row having eight Holes.

Being thus furniflied with a Repofitory
for your Colledion, and provided with
ninety-fix Phials of clear Glafs to place in
thefe Holes, where they will ftand in Order
without Danger of tumbling down or be-
ing otherwife difplaced, put into each Phial
as much of any Salt or faline Subftance,
reduced to Powder, as you are certain will
he fufficient to faturate about half the
Quantity of Water it can contain ; for 'tis
heft to prepare no more at once, as thereby
you will leave Room for making Mixtures
and trying Experiments, which if the
Bottles are quite full you cannot do fo well.
Then with a Tea-fpoon, half fill your
Phials with boiling Water, immerging them
all the while up to the Neck in a Bafon
of Water, likewife boiling hot *, and hold
them there till the Salt is all diftblved, or

This done, faften with ftiif Pafte a fmall
Piece of Paper on the Side of each Phial
near the Neck, that it may eafily be feen;
having previoufly marked the Papers 1, 2,
3gt; 4, 5. in a numerical Order. Fit

the Phials with good found Corks, on which
you muft likewife mark the fame Numbers,
that you may not miftake the Bottles they
belong to: and do not think it enough to
mark the Corks only, for many of the
Salts will deftroy the Marks upon the
Corks, and by that means leave you in the
Dark as to what they contain, unlefs
there are Papers alfo marked, to help you
out.

Make then an exad: Catalogue of them,
fetting down each Particular under a Number'
correspondent to that on the Bottle it is in ^
whereby you will at any time find readily
v.'hatever Solution you want to examine,
Yoa may range your Bottles in what Order
you think fit: that in this Treatife is per-
haps as good as any.

Thefe Preparations will keep good manr
Years ; and when any Phial is almoft out
it may eafily be replenifhed, fo as to pre-
ferveyour Colledlion always compleat. You
muft not expedf to fill all your Bottles
immediately; forty or fifty Sorts will be
perha|3S as many as you will foon be
able to procure; and therefore, if you fliall
be fatisfied with them, your Box may be
contrived in the above Manner to contain
only fome fuch Number. But a diligent
Enquirer will be able to add to them from
Time to Time, and would not willingly be
limited in his Refearches. Suppofe how-
ever

ever you have only forty Sorts -, by diffe-
rent Mixtures and Comportions of them
with one another, you may produce many
thoufands of Subjedls for Examination, and
be continually difcovering new and won-
derful Configurations : from this rich Store,
by combining different Salts, and in diffe-
rent Qiiantities, innumerable Varieties mav
be form.ed, as from the different Arrange-
ments of the twenty-foUr Letters of the
Alphabet, all the Sounds of Language may
be fignified.

Here is an unbounded Field, which I
only point out to the Curious, without de-
fcribing the Beauties I have frequently met
with in my Rambles there. 'Tis ënough
for me to fhew the Configurations and
Cryftals of Salts fimply and fingly ; I re-
commend to thofe who have more Leifure,
to examine them all differently combined.

Solutions thus prepared will be always
ready to fliew the Configurations forming
under the Obferver's Eye ; a Sight no one
can. behold without AdmJration and De-
light. It would likewife be very defirable
to preferve the Configurations themielves,
after they are compleat and perfe£l, or in
their different Stages : but this in general
cannot be done, for much the greater Part
of them are broken and deftroyed by the
Air foon after they are produced. A few
however are durable, and may be kept a
D 2nbsp;long

long while in good Perfedtion, if another
Slip of Glafs, of the fame Length and
Breadth, be placed over that the Configura-
tions are formed upon, with the Interpo-
fition only of a very thin Slice of Cork
between them at each End, to guard the
Configurations, by keeping the GlafiTes
afunder, from being any ways rubbed or da-
maged. A little Glew, flrong Gum, or
flicking Pafte, applied to each Side of the
Slices of Cork, will fallen the Glafles fo
well together as to make of them a Sort
of Boxes or Cafes, including the Configura-
tions, and defending them from any Injury,
if the open Sides be fhut up, by parting a
narrow Slip of Paper over them : but then
Pin-holes muft be made through the Paper;
for if the Air be entirely excluded, the Con-
figurations will foon decay.

I have now by me feveral of thefe little
Cafes of Glafs, containing Configurations and
Cryftals that appear nothing at all theworfe
for keeping, though they have been prepar-
ed at leaft four Years. Thefe are always
ready to fhew in a Minute, without any
farther' Trouble, and are a very pretty and
curious Set of Objedls. The GlalTes for
them are all cut by the Glazier of the fame
Size exadlly, viz. one Inch and three Quar-
ters long, and almoft an Inch broad. They
muft be free frbm Scratches, Flaws, or Air
Bubbles.

The Salts whofe Configurations or Cry-
ftals may be thus kept, are common Salt of
fome Kinds, not of all : Alum, fome of
the Vitriols, Sacchariim Saturni, Ens Veneris,
Salt of Amber, and fome others, which
are eafily known by their not breaking or
difiquot;olving away foon after they are pro-
duced»

A general Explatiation of the Plates, with
fome farther 'Thoughts on the Cryjlals and

Having declared already what I
mean by Configurations, and given
a full Account how to prepare faline Sub-
ftances for that Purpofe, and to make a
proper Colle6lion of them, little more is
requifite at prefent than to explain briefly
what the fol owing Plates defign.

Each Figure reprefents a Drop of the
Solution of that Subftance whofe Name it
bears; and is calculated to ftiew the Procefs
of its Appearances, from the firft beginning
to cryftalize about the Edges, to the full
and compleat Conclufion of all its feveral
Changes.

As Heat excites Aftion, and fets the faline
Particles in Motion, thofe Particles, whilft

floating in a heated Fluid, may be fuppofed
to have a confiderable Liberty of exerting
their attradlive and repulfive Properties, as
they approach each other in their Fits of Re-
pulfion or Attraction; or according to the
fortuitous Appofition or Approach of their
attradive or repulfive Points to each other;
whence a Commotion mufl necelfarily arife,
fome attrading and others repelling, till fuch
time as the Particles can difpofe them-
felves in the Order and Figure that muitl
neceffarily refult from their original Forms
and Properties : which Forms and Proper-
ties being fuppofed unalterablegt; how often
foever they are diffolved or feparated, they
will conftantly unite again in the very fame
Manner ®. And accordingly, in many of the
jFollowing Solutions innumerable little Maf-
fes may be difcovered, hurrying about moft
violently, and in all Diredions, before there
appears the leaff Tendency towards fhooting
jnto regular Figures.

■ The Solution being more Ihallow, and
the Attradion greater, about the Edges of
ihp Drop, than-near its Middle, the floating
Particles of Salt tend towards the Edges
in great Abundance, and begin there, mofl;

■ * Should the Particles wear away, or break in Pieces, the
^•».twe of Things depending on them would be ctianged.
Water and Earth compofed of old worn Particles and Frag-
jnents of Pariicks, would not be of the'fame Nature .and
■Texture now, with V/ater and Earth compofed of intire
particJes in the Begin.ning. Nenvtons. Opticks, p. 376.

commonly, to com.bine in fuch Cryftals
as are peculiar to the Subje£l; the Sides
and Angles of which Cryftals formed Vvdth-
in the furrounding Fluid are regular, po-
liftied, and tranfparent: and their oppo-
fite bides would be the fame alfo, were
they not terminated by the Edges of the
Drop, and unable to form themfelves upon
the dry Glafs.

This ufually is the Beginning of the
Procefs; and thus far the Power of iVttrac-
tion feems almoft wholly to prevail : a
Power whereto . Cryftalization appears al-
moft intirely owing; Repulfion, on the
contrary, may be deemed the firft Agent
in producing Configurations: or to fpeak
more plainly, Attradion, by making all the
Partic es within a certain ' Circumference
move towards fome certain Points, and
combine together in ar-regular Order, pro-
duces Cryftals; Repulfion, by puftiing them
outwards from fome certain Points, in a re-
gular Order, occafions Configurations, when
they are brought together again by Fits of
Attraction.

Should it be objeded, that our Configu-
rations may alio be produced by Attrac-
tion only, I muit prefume to think that is
fcarcely poflible ; for the Shoots that firft
appear do not only pufti forwards vigoroufly
in the Procefs, but divide and fubdivideinto
innumerable Lines and Branches j which
D 4nbsp;Divifion

Divifion and Subdivifion feem diredly con-
trary to the Effedl of an attractive Power;
fince Attraction can hardly be fuppofed to
make Particles of the fame horhogeneous
Matter feparate. I am however inclinable
to believe, that the Fits of Repulfion, which
pufti out the aforefaid Lines and Branches,
maybe attended or itnmediatelyfucceeded by
Fits of Attraction, laterally, in the Particles
compofing them; whereby the interme-
diate faline Particles difperfed in the Fluid
between the faid Lines and Branches are at-
tracted to the Sides, combine with, and
become a Part thereof. For was it other-
wife, when the Fluid is quite evaporated.
Particles of Salt would be found between
the Lines, which they are not in any Quan-
tity. Such a Propulfion forwards and At-
traction fideways, at, or nearly at the fame
Inftant of Time, may eafily be imagined, if
we fuppofe two oppofite Sides of the faline
Particles endued with an attractive, and two
other oppofite Sides of the fame Particles en-
dued with a repulfive Property, in fome fuch
Sort, as every Ray of Light is confider'd by
Sir IJaac Newton, in his Obfervations on the
douole Refraction of Ifland Cryftal, as hav-
ing * four Sides or Quarters, two whereof
oppofite to one another incline the Ray to
be refrafled after one Manner, and the other
two oppofite Sides incline the Ray to be re-
fraCted after a different Manner.

Cryftals and Configurations are frequently
feen together in the fame Drop, and form-
ing at the fame Inftant. As foon as the
Cryftals become difcernible by the Micro-
fcope, they are either Cubes, or Rhom-
boids, or Columns, or pyramidal, or trian-
gular, or fome other certain Figures ; and
to what Bignefs foever they may become
enlarged, they fhew, from their very firft
Appearance, the fame Sides and Angles that
are feen afterwards when at their utmoft
Size, no Alteration of Figure attending their
Increafe in Bulk. But the Configurations
change their Forms every Moment, pufliing
forwards in new Shapes continually, and
leaving no Refemblance of the Forms that
prefented firft : infomuch, that no better
Guefs can be made (in a Subjed never
before examined) what Configuration will
be form'd thereby, from feeing its firft
beginning Shoots, than from feeing the
Germen or feminal Leaves of an unknown
Seed one can pafs a Judgment what other
Leaves, Flowers and Fruit fuch unknown
Seed ftiall produce.

From the firft pufhing forward of the
Salt there is a continual feeming progref-
five Motion and Change of Figure ¹ : but

1nbsp; Notwithftanding this Manner of Expreffion, in Con-
formity to the Appearances of Things, 1 fuppofe the Con.
figurations of Salts are produced according to certain Laws
of Repulfion and Attraûion, whereby the floating Parti-
cles

as Motion can not be pidlured, I have en^
deavoured to fupply that DefeCt, by repre-
fentin^, in feveral Parts of the fame Drop,
the different Stages or Appearances that
are mofl remarkable during the vt^hole Pro-
cefs, and by giving a particular Account
thereof in the Defcription.

The cryftaline Shoots that prefent about
the Edges of the Drop demand our firft
Examination j and it Is advifable from their
very Beginning to keep the Eye conft-antly
£xt upon them, and to obferve their Growth.
In fome Subjects the Configurations pufh
cut from thefe Cryftals into an Infinity of
regular Branchings; but in others, and thofe
efpecially of the mineral Kind, the Cryf-
tals ihooting from the extreme Edges in-
to the ambient Fluid, preferve themfelves
feparate and entire, eveia through all the
Changes that happen, and by their Tranf-

dc;; of fiich Salts become arranged in certain determined
ptgures, according to their refpcitive Kinds, by Juxta-pofi-
tion. Accretion or Appofition, and not by any Protrnfion or
friooting forward.! in the Manner of the Growth of Plants.
And therefore though ^nniijing, footing out, branching, prt-
truriix?, and fuch like Terms, are frequently made ufe of in
the Courle of this Treatife, in order to avoid Circumlocu-
tion, and to render the Subjcft more familiar : the Reader is
clefired to take Notice and remember, that fuch like Expref-
fions are not to be underllood literaliy in the itridl Senfe of
the Words, as fuppofing any thing iimilar to Vegetation;
any more than among People well ft:illed in All/onomy the
gun is fuppofed aftualiy to moye from Eaft to Weft, to rife
ill a Moining and to go down at Night, though they fre-
Qutritly I'peak of its moving fo, of its rifing, and its going
tiovyn, in Confoimity to common Appearance.

parency, and polifhed Sides and Angles,
bear a near Refemblance, when enlarged
by the Microfcope, to the Shootings (in the
Fiffures of Rocks and Mines) of Spars,
Cryftals, and feveral Kinds of angular and
figur'd Gems, and ferve moreover to point
out after what Manner fuch Bodies are alfo
probably formed in a furrounding Fluid
and poffibiy too of limilar Materials: for
there feems nothing unreafonable in fup-
pofmg that different mineral Salts, diffolv-
ed in fome Fluid exfuding from Rocks
or Mines, and tinged with metalline Mat-
ter, may, through the wonderful Chemif-
try of Nature, fupply the different Sub-
fiance, Hardnefs and Colour of Spars, Cry-
ftals, and precious Stones; in fome fuch
like Way as their Refemblances are pro-
duced from the Solutions of fuch Salts J.
Nor are the Hardnefs of preciouis Stones,

• Cryftals and all angular Bodies concrete in the Midft
of a refolvent Fluid or Menflruum. The Fluid whereia
Cryftal is concreted, is to Cryftal as common Water is
to Salt. (Stem's Prodromus, Eng. Edit. Page 64.) That is,
fhe Cryftal Particles are feparated and float in fuch Fluid, as
the Particles of Salt do, when diffolved in common Water.

t Mines, or Beds of Metal, are met with conftantly, if
fought after, near the Places where precious Stones are
found. The Ruby is fuppofe4 by fonie to take its Teint
from Gold, by others from Iron ; the Emerald and Sapphire
from Copper, but by different Menftrua; the Topaz from
Lead or Iron, Qranates from Iron, Js'f. and a Mixture of
two or more Teints from different Metals may poffibiy give
Colour to the Amethyft, the Hyacinth, the Opal,nbsp;A

greater or lefs Proportion of metalline Matter may alfo ren-
der the Gem deeper or paler, harder or fofter.

their being void of any fahne Tafte, and
their Indiffolubility, fufficient Objections
againft Salts being the Bafis of Diamonds,
Rubies, Emeralds, Granates, ^c. fince it
is obfervable, that Glafs, in whofe Compo-
fition Salt is a principal Ingredient, proves
alfo undilfolvable, is endued with a con-
fiderable Degree of Hardnefs, and (as its
component Salts cannot aCl unlefs diffolved)
is confequently infipid, or rather abfolutely
taftelefs.

Whoever fliall pleafe to repeat thefe Ex-
periments after me, will I believe be fa-
tisfied, that the Cryftals fhooting from a
Solution of diftilled Verdigreafe, which
is a Vitriol loaded with Copper thofe Cryf-
tals I mean whofe Roots are at the Ex-
tremity of the Drop, and their Points in the
ambient Fluid, refemble nearly the fhoot-
ings of Emeralds both in Figure and Co-
lour : that the Cryftals of Ens Veneris, a
Preparation of Iron, vsronderfully emulate
the Topaz,

When the faline Particles combitie, without any metal-
line Admixture, the Concrete appears colourlefs, and
probably forms pure Cryllals or Diamonds. The extreme
Hardneft and Luflre of the Diamond refult perhaps from
the almoft abfolute Homogeneity and Purity of its component
Particles, whofe Sides or Planes having admitted no foreign
Particles between them, touch in many Points, and be-
come thereby alrooit infcparable. Saline Particles in fuch
Purity meet, however, but very feldom, and in fmall Quan-
tity : but as mineral Salts abound almoft every where, and
efpecially about Rocks and Mines, they frequently appear
in Shoots or Maffes, blended more or lefs with talcky or other
Matter, and probably conttitutc our Cryftals, Spars, l^c.

No Kinds of Matter that we know of,
except Salts, have a Tendency to fuch-likc
Figures : but Salts when at Liberty always
appear in them. The Tranfparency of
Salts is alfo another Property almoft pecu-
liar to themfelves and the Bodies we are
fuppofing them to compofe : and therefore,
notwithftanding in thefe our hafty and im-
perfect Experiments the Shoots are fo mi-
nute as to require a Microfcope to difcern
them, and fo tender that the Air in -a
fhort Time deftroys them, may not Nature,
who proceeds furely, though flowly, pro-
duce Bodies from a better Combination of
the fame Kinds of Materials, of Size pro-
portionable to the Quantity of fuch Mate-
rials, fimilar in Figure and Colour, hardly
feparable, and of long Duration ?

I have dwelt the longer on this firft
Part of the Procefs (which the Drav/ings
point out in the Shootings of dijlilled Verdi-
greafe, Plate II. 1, i : in thofe of Alum,
Plate III. ^ ^and of Ens Veneris, Plate IV.
a a) fince every Obferver muft be highly
pleafed, to behold the beautiful Appearances
of Emeralds, Diamonds, amp;c. rifing as it
were from their native Bed, forming their
regular Sides and Angles under his Eye, and
glittering with a Brilliancy and Colouring
hardly to be imagined.

appear forming within the fame come next
under Examination : and thefe, from their
very firft becoming difcernable, being en-
compafled on every Side by a Fluid re-
plete with faline Particles, (which, fwim-'
ming at Liberty, are attrafted or repelled
from every Quarter, till the Points of greateft
mutual Attradion meeting in Contad, com-
bine according to theirrefpedive Figures'}-:)
Thefe, I fay, have all their Sides moft com-
monly regular and compleat, with fuch
Number and Difpofition of polifli'd Planes
and Angles as fully diftinguifti from what
Salt they are derived.—Thefe are the Cryf-
tals that were before mentioned to retain
their Figure however their Size enlarges 3
They, and they alone, are properly to be
termed the Cryftals of fuch Salt, and many
of theni in Elegance of Form and native
Luftre excel the Workmanftiip of the moft
expert Jeweller. Thefe are intended to
be reprefented in the Alum Solution at f,
and in that of Ens Veneris at b b. They
are alfo (hewn again by themfelves, and in
a larger Size, under thofe and fome of the
other Drawingsi

t All foflil Cryflals, Gems, and other Bodies that have
regular Planes and Angles, without an Appearance of being
broke off froA any Root or Stem, are probably formed in
the fame Manner.

After the Cryftals about the Edges are
grown large, and thofe farther within the
Drop have likewife pretty nearly attained
their full Size; in the Solutions .1 meart
where fuch Cryftals do form; for feveral
Kinds produce Configurations but no Cryf-
tals ; and, on the contrary, in fome few,
niz,. of Sal Gem, common Salt, though
Abundance of Cryftals are produced, no
Configurations at all appear : After, I fay,
the Cryftals are formed, the Configurationsr
begin to ihoot, proceeding fomewhat llow-
ly at the firft: but they quicken by De-
grees, and dart at laft, in many Subjedlsv
quite over the whole Drop, as fwift aa
Lightning ; and that efpecially if the Drop
has been too much or over fuddenly heat-
ed. Therefore when the Configurations
once begin, the Eye fhould never be taken
off, till they are entirely finifhed. Some
Defcription of them is given under each
particular Subjedt, and they are reprefented
in the Drawings, as the third Stage of the
Procefs, fignified by c, D, e, F, G, in the
Alum Drop, and by c and d in the Drop of
Ens Veneris.

Thefe Configurations are no lefs con-
ftant in their Forms than the Cryftals are,
infomuch that each Subjed is eafily dif-
tinguifhed by them. They feem compofed
likewile of the fame tranfparent ftiining
Particles: but the Figures they produce

are fo extremely different, that every con-
fiderate Obferver mufl judge them owing
to fome very different Property in Nature.—
I have ventured to mention AttraClion
and Repulfion, as two Principles that we
may fuppofe concerned in producing thefe
different Appearances, but am very far from
being obflinate in this Opinion, or un-
willing to recede from it, whenever any
more probable Caufe can be affigned. I
am fufhciently fenfible how liable we are
to be miflaken, and how very little we
know even of the moft common Things.
The very Elements that are continually
about us, the Fire, the Water, the Air we
breathe, and the Earth we tread upon, have
many Properties beyond our Senfes to reach,
or our Underflanding to comprehend : and
when we imagine we know any one Thing
perfectly, I am afraid we flatter and de-
ceive ourfelves very grofly. It is our Hap-
pinefs, however, and our Duty, to beflow
fome Time and Pains in making ourfelves
acquainted with the Productions and Changes
that Providence continually brings about
in a regular and conftant Manner. We
are able to fee EffeCts, though their Caufes
are beyond our Knowledge: but as no
Effect can be produced without fome Caufe,
when we behold Order, Harm^ony, and
Beauty arife out of Confufion, by means
of certain aCtive and unalterable Properties,

wherewith the Author of Nature has en-
dued the original Particles of Matter ; thougk
we cannot underftand the mechanical Ope-
ration of thefe Properties, or know really
what they are or can perform^ we fhould
raifé our Contemplations and Adoration to
that Eternal, Omnipotent, Supreme Firft
Caufe, who is incomprehenfible in all his
Works : and here, perhaps, here only, our /
Ignorance may commendably become the
Mother of our Devotion.

In fhort, if the Cryftals of faline Sub-
ftances are wonderful, their Configurations
are infinitely more fo : their Variety and
Beauty no Words or Language can poflibly
exprefs ; and trying to give the Pidlures of
them is like endeavouring to paint the LuA
tre of a Diamond, or the Brightnefs of the
Sun-fliine.

It happens in fome Kinds of SolutionSj,
that after'the Cryftals are formed, the Con-
figurations perfefted, and when every thing
feems over, and all is quiet, other new Con-
figurations, arid Cryftals too, prefent them-
felves, in Figures very different from the
former, and what probably are owing to
Salt of another Kind that was latent in the
Mixture.

f~^EM-Salt diffolved in warm Water, and
^^ a Drop applied to the Microfcope on a
Slip of Glafs, either holding it over the Fire
for a little while to haften the Experiment,
or leaving the Water to evaporate at leifure,
affords the feveral Figures that appear in the
firff Plate, I.

The Figures of Spring-Salt, or Bajket-
Salt * , obtained by the fame Method, are
ftiewn at III.

The Figures of thefe three Salts differ
very little: each of them producing Bodies
of the like Forms; viz. folid Cubes,
fquare Plates, and hollow Pyramids, hav-
ing Bafes that are either exaCt Squares, or
Rectangles, and whofe Hoping Sides dimi-
nifh gradually upwards by a kind of Steps,
fome terminating in a Point, and others
appearing truncated, or ending with plane
Surfices. Each Kind of thefe Salts does
not however produce the fame Figures in
equal Plenty, for Gem-Salt affords moft
Variety; Sea-Salt abounds chiefly with

* This does not mean that all Salt made from Springs is
Bcjket-Salt, but only that our BaJketSalt is one Kind of
Sai; made from Springs«

Moft Writers reprefent the Cryftlls of
thefe Salts as Cubes ; and fuch in Truth
they feem originally to be : I mean, when
fo minute as juft to become diftinguiftiable
by the greateft Magnifier : large Mafles of
Sal-Gem, and fometimes of Sea and Spring-
Salt, are feen in cubical or reftangular
Figures, made up without doubt of innu-
merable minute Cubes. But in all Exami-
nations by the Microfcope of the Solutions
of thefe Salts, the Bodies that form and
grow under the Eye are, in the general,
not Cubes, but hollow Pyramids : though a
Prepoffeffion that the Cryftals of fuch Salts
are Cubes, makes thefe Figures, even under
Infpeftion, often imagined fo to be: for
the fquare Out-line, which is only the Bafe
of an hollow Pyramid (if great Attetition
be not employed) is apt to give the Idea of
a Cube: and the different Ranges or Steps,
which by a gradual Diminution upwards
compofe the Hoping Sides of the Pyramid,
are eafily miftaken, from their great Tranf-
parency, to be no other than Lines upon
the Surface of the Cube. Indeed a few
Cubes are feen now and then amongft the
other Forms, but their Number is far too
fmall to conclude the general Figure from :
thofe very Cubes in fome Pofitions have
E 2nbsp;- likewife

I have examined various Species of thefe
Salts from different Parts of the World, and
particularly feveral brought from Egypt,-
Hungary, Germany, amp;c. by my worthy and
ingenious Friend Dr. Richard Pocock, Arch-
deacon of Dublin, and F. R. S. which,
tho' red, brown, white, amp;c. and feemingly
of very different Contexture, fome appear-
ing fibrous, others fparry, talcky, amp;c. yet,
when diffolved and examined, much the
greatefl Part of the regular Bodies produced
in them all were of the fame general Fi-
gure, /. e. hollow Pyramids-, with little
farther Difference, than that fome were
more tranfparent and fharper at the Top
than others. It may therefore reaibnably
be concluded, that an hollow Pyramid,
either pointed or fiat, is the general Figure
■ of all FoJJile, Sea, and Spring-Salts, when
after being diffolved, and a fmall Degree
of Heat given, their Particles are brought
together, and unite again according to the
Order and Difpofition of Nature whichquot;
hollow Pyramid is compofed of minute
Cubes moft regularly and wonderfully com-
bined And this has been demonfiratcd

even to the naked Eye by the Salt made
after Mr. Thomas Lowndes's new Method,
where Multitudes of fuch regular pyrami-
dal hollow Bodies may be found, compofed
as it were of a Number of little Stairs ; and
fo large, that each Side of their fquare
Bafe is at leaft a Quarter of an Inch in
Length

None of thefe Salts afford any Branch-
ings out: the Appearances round the Edges
of the Drop, when Heat is applied, being
nothing elfe but a Congeries of faiine Par-
ticles hurried together with very little Re-
gularity, and producing no new Forms:
for which Reafon thefe Combinations are
not reprefented in a Drop, as all that ftioot
into Figures more different are. But not-
withftanding the general Shape of thefe
Bodies is nearly the fame, there are parti-
cular Differences very v^'ell worth obferving,
which the Drawings endeavour to exprefe.

is fuffered to fnoot into its true Form, its Cryftals are found
of a .cubical Figure of various Sizes: and many of thefe
fmaller Cryltals are united together into hollow Pyramids
with a fquare Bafe. Thefe Pyramids are truncated, being
not finilhed at the Top, but having there fixed a Cube of
Salt of a more than ordinary Bignefs.

* Mr. Lowndes fays, quot; in the Salt made by the Sun, as
quot; well as by my Way, you will never fail of feeing very
quot; many little Pyramids, which are compofed of a Parcel of
quot; fmall cubical Grains piled up in a moll exaft Order, and
quot; cemented together with wonderful Nicety : and the
quot; Crowns of thefe Pyramids are always Cubes of a much
quot; larger Si?e than any of the rell.quot; VifJ. Brine Salt imr
prsued, p. 16.

Ä - A fquare pyramidal hollow Body, fome-
what opake, whofe four Sides are
floping Triangles, and meet in a Point
af Top.

h - h body with four equal floping Sides,
terminated by a Plane at about half the
Height of the former : not much tranf-
parent, but hollow.

C - h Body rifing about the Height of the
lafl:, in the Manner here fhewn, and
very tranfparent except as the Lines
imply.

s - An hollow Pyramid, whofe Bafe is a
Redtangle, and whofe Sides are flop-
ing and terminate in a Point the
whole femi-tranfparent.

ƒ - A narrower hollow Reaangle, with
floping Sides not much tranfparent,
riflng about half as high as the pre-
ceding, and then ending in a flat Sur-
face that is very tranfparent.

g - Another hollow Figure, having a red-
angular Bafe, very tranfparent, with
flopingquot;Sides as in the Pidure.

h'hn hollow Body, whofe Top is a large
tranfparent Square, and whofe Sides are
darkifh in the Middle, but very tranf-
parent at the Ends, whereby the four
Corners become alfo tranfparent.
/-A very pretty tranfparent truncated pyra-
midal Figure, whofe Top is alfo a tranf-
parent Square, and whofe four Corners
appear to open and feparate.
k - K folid Cube, femi-tranfparent.
/-Another Cube, which by its Pofition, if
carelefsly examined, will probably be
iniftaken for an Hexagon.
m- K fquare Plate of fome Thicknefs, but
tranfparent: its Situation makes it feem
a Rhombus.
nn - Two oblong Plates, extremely thin and
tranfparent, with a Spot in the Midft
of each.

0 - A fquare Pyramid, hollow, and pretty
tranfparent, wherein a Kind of Steps
appear gradually leffening upwards.
P - Another Figure about half the Height of
the preceding, whofe Top a very
tranfparent fquare Plane, and whofe
four floping Sides are graduated and
conjjderably tranfparent.

After the Defcriptions already given, 'tis
'Tieedlefs to fay more of the four following
Figures, q, r, s, t, than that they alfo are
hollow pyramidal tranfparent Bodies, with
fuch different Graduations as themfelves
pretty tolerably reprefent.

•V, w - Two of the large hollow Pyra-
mids of Mr. Lowndes^ Salt, drawn in fuch
a perfpedtive View as may heft exprefs
their real Figure ; each having a fquare
Eafe, and four triangular Sides that are
nearly equal. Many fine Lines appear run-
ning acrofs thefe Sides parallel to the Bafe,
which, on a ftrifl; InfpeCtion, are found
to be a regular Graduation of Steps, leffen-
ing from the Bottom upwards. Thefe Py-
ramids do not commonly end in Points, but
are terminated by a cubic Figureeach Cor-
ner of their Bafe is alfo frequently fupport-
ed by a Cube, but of a fmaller Size ; and
ftill lelfer Figures of the fame Shape appear
along the linear Edges, in Number equal to
the Steps, and clofing the Angles where
they join. There are Graduation? within-
fide thefe Pyramids correfpondent to thofe
without, like the Underwork of a Pair
of Stairs. The Size here exhibited is

It is very well worth remarking, that
amongft the many pyramidal Figures pre-
fenting themfelves in a Drop of the Solu-
tion of thefe Salts, every one feems to ftand
ereft upon quot;its hollow Bafe, and appears,
when under Infpcftion by the Micro-
fcope, exadly in the fame Manner as repre-
fented in the Plate: but this is a Deception;
for in Double Microfcopes, compounded of
three convex Glaftes after the ufual Man-
ner, all the Parts of an Objed are feen in-
verted ; that is, the Top appears at Bottom,
the left Side on the right, amp;c. The Lights
and Shades being alfo inverted, the finking
Places appear to rife, and the rinng Places ■
to fink in : fo that in Truth the hollow
Bafe of the Pyramid is really uppermoft
and next the Eye, tho' it feems to be quite
otherwife. And in Confirmation of this,
I was allured by Mr. Lowndes, that in the
making his Salt, nothing is more common
than to fee the Pyramids forming upon the
Surface of the Brine, and always with their
truncated Ends downwards

* We are told in the Memoirs of the Royal Academy ef
Sciences for the Year 1700, that Monfieur Homherg ftievved
a little Pyraaiid of Salt, formed in a Cryftallization. It
was but low in Proportion to its Bafe, hollow within, and
its Bafe was uppermoft during the Time of its Formation ;
which Monfieur Hamherg thus accounts for. There was
formed, fays he, at firft, a little Cube of Salt (the Figure
Salt natvwally afFefts) on the Surface of ths faked Water.

We begin our Experiments with that
pative foffile Salt, ufually called Rock-Salt
from its Place of Growth, and from its
Clearnefs Sal-Gem; as it is probably the
Principle or Bafis of feveral other Salts.

Sea Water owes its Saltnefs moft likely
to vaft Quantities of this Salt diffolved there-
in J which, being extradled by different Me^
thods, becomes either Bay-Salt, or what
we commonly call Kitchen-Salt: and Springs
running through or over Beds thereof, and
becoming faturated therewith, afford by
Boiling and Evaporation all our Inland or

This Cube did not fink, though heavier than the fait Water,
any more than a Needle, if laid on Water gently, would do.
and for the very fame Reafon : for when a Needle is placed
in fuch a Manner on Water, a little Hollow is made about
it, tilled with Air only, in which it lies as in a little Boat;
becaufe the Bulk of the little Hollow and Needle together
is lighter than Water of the fame Dimenfjons. A fimilar
Hollow was formed about this- Cube of Salt, which enter-
ed a little into the Water without finking j its upper Sur-
face was dry, and rofe above the Surface in the Hollow,
though not fo high as the general Surface of the Water
round n. Other Cubes of Salt cryftallizing along the four
Sides of this dry Surface began lo form a fmall hollow
Square, or which the firlt Cube compofed the Bafe. Thefe
little Cubes, when joined together, becoming heavier than
the firft fingle one, and being encompaffed with lefs Air ia
Proportion, from their Junflion to the firft by their inner
Sides, funk ftill deeper in the Water, that is, to the upper
Surface of the little Cubes which adhered to the firft Cube.
New Cubes of Salt adding themfel ves to thefe, funk the Bo-
dy yet lower down ; and others continually joinino- them af-
ter the fame Manner, by enlarging the hollow Sqliare, ftill
plunged it more and more, and formed the inverted Pyra-
mid; which growing at laft too heavy, funk to the Bottom
of the Water, and then increaled no more.

Bajkei-Salt fo that, in Reality, Rock-Salt^
Sea-Salt, and Spring-Salt, are derived fi'om
one and the fame Original in the Bowels of
Rocks and Mountains ; and, upon the ftrift-
efl: Examination, they feem to differ no
otherwife than by fome adventitious Mix-
tures, as our Experiments evince, by fhew-
ing tlaat neither of them form any branch-
ed Configurations; but when their Particles
combine again after Diffolution, they con-
ftantly compofe the fame Kinds of pyra-
midal Cryftal Bodies, with Bafes that are
either exafi: Squares with four equal Sides,
or elfe having two oppofite Sides longer than
the other two, but always making a right-
angled Figure,

This Salt is conveyed by Springs and
Rivers wherever their Waters can find a
Paffage. Its fineft Particles rifmgwith Ex-
halations from the Sea and other Waters,
are likewife difperfed univerfally, and fa-
turate the Surface of the whole Earth: where
entering the Roots of Plants, they promote
Vegetation, help to compofe their folid
Parts, afcend with their Juices, and, ac-
cording to their Mixture with them, pro-
duce that amazing Variety of Taftes, Smells,
and other Qualities. Some of this may be
recovered in its original Form, by Art, from
moft Kinds of Vegetables; while the reft
becomes fo changed by being blended with
other Subftances, as to appear in the Shoots

or Cryftals peculiar to each Sort of Plant,
and probably conftitutes its effential Salt.

'It is alfo taken continually into the Sto-
machs of Animals, their Food abounding
with it, and affording them proper Nutri-
ment by the Means thereof. It diffolves in
and circulates with their Blood and Hu-
mours, and becomes fo highly fubtilized by
the Heat and Adlion of an animal Body,
that the greateft Part of it is rendered vola-
tile, ar.d can hardly be reduced again into
its original Figure, though fome of it may
alway^ be found unaltered in the Blood,
Urine, And the Fertility which Dung
produces in barren Soils, is owing to the
Abundance of it contained therein : _ for
though Salt in its natural State is prejudicial
to Vegetables, it becomes fo tempered, after
having pafied through the Bowels of living
Creatures, and been intimately mingled with
their putrifying Fffices, that it caufes them
to thrive exceedingly.

No Menftruum is yet found to diffolve
Geld, unlefs one of the Salts we are treating
of be an Ingredient therein ; they being
the only known Diffolvents of Gold, as
'Nitre is of Silver: but, on, the contrary.
Common Salt, Rock-Salt, or Spring-Salt,
mixed with Aqua Fortis or Spirit of Nitre,
will prevent its dilfolving Silver, though
fuch Mixture proves the readieft DifTolvent
of Gold.

The peculiar Excellence of thefe Salts
for the Prefervation of Flefh, Fiili, amp;c. is
too well known to need Defcription ; and
their other extraordinary Virtues, when pre-
pared in different Ways, are too many to be
mentioned here. Glauber aiferts, that com-
mon Salt is the moft ufeful and moft ex-
cellent of all the reft, being the Princi-
ple whence all other Salts, either known
or unknown, are chiefly derived, and may
by Art be produced. By a little Labour and
Fire, and the Addition of fome metallic
Sulphur, it may, he fays, be converted into
Alum or Vitriol; by Fire, Air, and Sulphur,
into Salt-Petre ; by the Help of a fiercer
Fire, into an alkalious Salt, and by deftroy-
ing its Acridity, into a Salt fit for enriching
Land, and extreniely ferviceable to fandy
and barren Soils

Common Salt diflfolved in fharp Vinegar,
and a Drop thereof a little heated, fhoots
fome pretty Configurations from the Edges»
and affords Cryftals of the Figures juft now
defcribed, extremely clear and beautiful,
though fmaller than ufual. Thefe frequently
are joined together with a curious Variety
of Compofition, which the Ci7ftals of the
fame Salt difl'olved in Water never exhibit
for they commonly form feparate and dif-
pofed at Diftances from each other.

Diffolved in Spirit of Wine,. it likewife
produces Configurations, but very different
from thofe in Vinegar, with Cryftals fmall-
er than ordinary, and having, little or no
Tranfparency.

Dr. Boerhaave fays, thefe three Species
of Salt diffolve alike in three Times and a
Quarter of their own Weight of Water * :
hut I have found a confiderable Difference
in different Waters, and in different Portions
of the fame Salt.

r-piHlS Salt being diffolved in Water*,
I a Drop of the Solution ftioots from
its Edges, with very little Heat, into flattifti
Figures of vafious Lerigths, exceedingly
tranfparent, and with Sides that are ftraight
and parallel, Thefe are ftiewn .in their dif-
ferent Degrees of Progrefiion, at the Letters
a, b, c, d, e, Plate I. N^ IV. where a repre-
fents how they firft begin.

Many of them appear cut floping at the
Ends down to a ftiarp Edge, in the Man-
ner of a Chiffel, and are fome wider and
others narrower. Several alfo are found

With one Corner taken off obliquely, and
that in different Angles; leaving the other
Corner fometimes quite a Point, and fome-
times having a little Breadth.

After Numbers of thefe are formed, they
will often diffolve again under the Eye and
entirely difappear -, but if one waits a little,
new Shoots will pufh out, and the Procefs
go on afrefh. Thefe firfl Figures fometimes
enlarge only, without altering their Shape,
and fometimes form in fuch Sort as the
Drop reprefents ; but if the Heat has been
too great, they fhoot haflily into nume-
rous Ramifications, very regular and beau-
tiful, but which we have not attempted
to draw, from the great Difficulty of doing
it. There feems all the while a violent
Agitation in the Fluid j and moft commonly,
towards the Conclufion, a few Oûaëdra
(compofed of eight triangular Planes, or
two quadrangular Pyramids joined Bafe to
Bafe) appear ; which belong probably to
fome other Kind of Salt intermixed with
the Nitre : Pyramidal Figures of common
Salt are likewife fometimes feen; and of
thefe I have now and then found the greateft
Plenty when the Nitre has feemed moft
white and pure, which I pretend not to ac-
count for, unlefs common Salt has been
employed to make it fo.

The regular Cryftals of Nitre are repre-
fented underneath the Drop, greatlv magni-
fied

nified according to iny Method of Exaiaii-
nation, though indeed lefs than what mdy be
found when large Quantities are prepared in
the common Way; and confifl: of fix pa-
rallel Sides or Planes, which compofe Bo-
dies of different Lengths, and differently
terminated at the Ends. There is alfo a
confiderable Variety as to the Equality and
Inequality of thefe fix Sides. The moft
common Cryftals are fomewhat flat, and
have two broad parallel Planes oppofite to
one another, and four that are much nar-
rower J two of which (viz, one that goes
Hoping from the upper, and the other frortl
the under Plane) meet on each Side, and
conftitute a pretty fharp Edge. One End
of thefe is commonly cut off floping on
both Sides along its whole Breadth, but
feldom in the fame Angle. Fid. Fig. i.
Sometimes however there are four broader
Planes, and only two narrower j and now
and then the Sides are pretty equal j and
their Bafe is nearly an equilateral Hexagons
The feveral Differences in the Drawing are
likewife to be met with, as well as fome
others, but the rareft as well as the prettieft;
is that at Fig. 6.

The beft Way to obtain thefe Cryftals for
the Microfcope, is by faturating fome warm
Water in a Spoon w^ith Nitre (not with
more however than it can perfeftly diffolve) j
when in a few Minutes little Concretions

will be feen forming at the Bottom, which
being taken up on the Point of a Penknife,
before they are grown too large, and placed
with a little of the Fluid on a Slip of Glafs,
will be found, if they are not broken by
the Removal, to have amongft them fome
or all of the Figures fhewn in the Drop,
and again reprefented in a larger Manner
underneath the fame. And though the
Cryftals thus obtained are exceeding fmall,
they are much more intire, diftinft, and
true, than what by concreting in vaft (^an-
tities become Millions of Times bigger,
as they are frequently feen in the Shops.
Amongft thefe too may be found many
Cryftals perfedl at both Ends, by having
been formed wholly detached in the fur-
rounding Fluid, whereas thofe wc get by
any other Method are almoft conftantly
broken at one End, from their having been
fixed thereby to the Side or Bottom of the
Vefiel they were formed in, or elfe to one
another.

cut oflf more obliquely, and compofing
an hexangular Plane. The Sides of
this Column are four broader and two
narrower Planes, whereas the prece-
ding confifted bf two broader and four
narrower.

Sides : one End broken, and the other
forming an hexangular Pyramid, whofe
Sides are correfpondent to thofe of the
Column.

both whofe Ends are Pyramids, having
Sides that correfpond with thofe of the
Column.

One Particularity in Nitre is, that its
Cryftals are perforated from End to End
all along, juft within the Corners where the
Planes interfedt; as may be proved in the
larger Shoots, by the Breath's pafling thro'
them eafily on blowing. Thefe Channels
are pointed out in Figure 2, by the fix
Dots at its End; they are likewife fliewn
more perfedly at Fig. 7. which reprefents

This Salt is found juft under the Turf
about Fatnefs in the Northern Parts of the
Kmgdom of Bengal, and probably in other
Places thereabouts, whence it is brought
to us in great Abundance by the Eaji-.
India Co?npany ¹ : but all produced in Europe
appears either like a kind of Efflorefcence
adhering to Rocks and Walls, being what
the Ancients called Aphronitmn, and what
IS called by us Natural Salt-Petre, of which
the Quantity colledled is but fmall; or is
elfe extrafted by Art from certain Earths
and Stones, the Ruins of old Buildings,
the Dung of Pigeons, and the Excrements
and Urine of other Animals: the Man-
ner of doing which is related by feveral
Authors.

Examin'd chemically (and to ufe the Che-
mifts Terms) it appears compounded of a
volatile acid Spirit, and a fixt alkalious Salt.
Jmch a Spirit the Air abounds with: and
pis Spirit by penetrating into, and becom-
ing incorporated and fixt by the alkali-
ous baits of Lime, and fome Sorts of Earth
and btone, is probably the active Principle
tnat produces Salt-Petre. It is alfo very
likely owing to the fame Principle, that Salt-

Petre may conftantly be obtained from the
Mortar and Rubbifh of old Walls, which
have been long expofed to the Air; and that
the fame Materials, after being divefted of it
by Art, will afford a farther Quantity by
lying a few Years together. The extreme
Hardnefs of the Mortar in fome old Build-
ings, where it is found more difficult to be
broken than even the Bricks or Stones it
ferved to cement, feems likewife occafioned
by its being fo fully impregnated with this
Spirit ^ or Principle, that it becomes.in a
manner petrified: and the alkalious Salts
wherewith the Excrements of Animals
abound, ferve probably, in the like Manner,
to fix and embody the fame Spirit, and
conftitute Salt-Petre. Some have under-
taken to make it likewife from Lime, Pot-
Afhes, amp;c. but hovv'foever it be produced,
it may always be diftinguifhed by its hex-
agonal Shoots.

Let us now confider what other Pro-
ductions of Nature appear in this hexago-
nal Figure; and we fliall find that all
Cryftal, unlefs either ftraitened for Room

* May not wbr.t we call a volatile Spirit confift of Pani-
cles exceedingly minute, and of fome determinate Figure ;
whofe Property it is to repel each other, from certain Pcints,
in certain Direfiioiis, ai!4 to certain Diftances; whereby
they are unable to combine together, unlefs by penetrating,
mixing, and becoming embodied with other Matter, whofe
Pores they can ftrike into ? and may not their repulfive
Power be increafed by Heat or Motion ?

or overcharged with foreign Matter, is con-
rtantly formed into Pyramids of fix Sides,
or into hexagonal Columns terminated witia
fuch Pyramids, and refembling the Nitre
Shoot 5. And as thefe Cryftals fhoot moft
commonly from Pvocks of calcarious Stone,
may not their Form be owing to the fame
volatile Spirit, more ftrongly fixed and em-
bodied, and compofing a m.ore hard and
tranfparent Subftance, by an Admixture
with fome Matter different from that where-
with it compofes Nitre? And if, inftead
of exfuding from Stones, and adhering
thereto by one End, ufually called a Root,
thefe Principles happen to concrete in fome
Fluid, or other foft Bed, where both Ends
are equally at Liberty to fafhion themfelves
according to the Inclination of their compo-
nent Particles, may we not fuppofe they
may then produce * thofe fparry or cry-
ftaline Pyramids, joined Bafe towards Bafe
by the Intervention of an hexagonal Column
which are known by the Name of
Diamonds, from the Place where found
moft plentifully ; and which in Figure re-
ferable exadlly the Shoot of Nitre 6 ?

are always hexangular, or with fix Points
nearly refembling the Bale of the Column
of Nitre i, or thin Slices of fuch a Column
cut ofFtranfverfely: and as freezing is ufually
imputed to the Redundance of Nitrous Par-
ticles in the Air, thofe who embrace that
Opinion will probably find little Difiicul-
ty in fuppofing this Form of Snow occa-
fioned by the fame Principle that gives an
hexagonal Figure to Nitre: and perhaps
they are not miftaken in fuch a Suppofition,
though there is fome Reafon to believe they
may be fo as to the Abundance of the Par-
ticles of Nitre they imagine exifting in the
Air.

The continual Perfpiration of growing
Vegetables; the Putrefadion and Diffolution
of thofe that perifli over the Face of the
whole Earth, all which abound with vola-
tile acid Salts the continual Exhalations
from Seas, Lakes, Rivers, and other Vi^aters,
which carry alfo up with them Abundance
of the finefl Particles of Mineral or Sea
Salts; the Steams and Vapours from Metals
and other Subftances: all thefe compofe to-
gether the volatile acid Spirit wherewith th§
Air is filled, and which probably is the ac-
tive Principle that gives the Figure, and
fupplies Part of the Matter to Cryftals,
Snow, and Nitre.

* The Flakes found now and then with twelve Points, are
probably two Flakes, whofe flat Surfaces are ftuck together,
with their Rays ajternatelv diipofed.

But the Particles of this acid Spirit are
no more the Particles of Nitre, than Nitre is
the Gunpowder which it compofes by the
Addition of Sulphur and Charcoal. And
the Truth of this feems confirmed by the
Impoflibility of obtaining a fingle Grain of
real Nitre, from any Quantity of Snow or
Ice : whereas Nitre being but little volatile,
fome of it certainly would be found if it was
really there. However, though no Nitre
can be found, after the volatile Salts that
link'd the Particles of Water to one another
are driven out by Heat, and the Water be-
comes fluid, it is obferved to be much harder,
or lefs fit to make a Lather with Soap, than
it was before its being frozen, from its re-
taining fome fmall Portion of the acid faline
Particles, in the fame Manner as any Water
may be rendered hard, by putting into it a
few Grains of common Salt, or a few Drops
of any acid Spirit.

'Tis probable thefe acid Spirits are pro-
duced every where; but being extremely
volatile, and eafily driven away by Heat,
they foon become diffipated in thofe hot
Regions, under, or nearly under the Sun's
airedt Rays, unlefs they are immediately
embodied by mixing with fome other Mat-
ter ; and confequently, thofe Countries
nearer the Poles, whereunto they are driven
by the Sun's Heat, muft abound with them,
more or lefs, in proportion to the Ability or
F 4nbsp;Inabi-

Inability of the Sun's Rays to drive them
again from thence : and thefe extremely
minute and adive Particles, being continu-
ally in Motion, ftrike into, penetrate, and
fix between the Pores of all Bodies capable
of receiving them. Thus, mixing with
faline Exfudations from, or certain Salts
contained in Earths, Stones, amp;c. they may
probably incorporate therewith, and con-
crete into the hexagonal Shoots of Cryilal :
filling up the Interftices of Water, and
becoming therewith embodied, they com-
pofe that hard Subftance we call Ice ¹ ;
which differs nothing from Cryftal in Clear-
nefs, and perhaps would h ave the like Form,
did not the Quantity and Situation of the
Fluid prevent it ; fince we find that Water,
falling in fmall Drops, is concreted with
the fame Particles into an hexangular Fi-

Thefe Particles ftriking into the Bodies
of living Animals occafion the Senfation of
Cold : if their Quantity be great, they pro-
duce firft a fevere Pain, and then a Numb-
nefs, by impeding the Circulation of the Ani-
mal Fluids ; and if they are not driven away
by Heat from Motion or olherwife, or their
Cgt;uantity be much increafed, they ftop the
Circulations entirely, and bring on certain

1nbsp; The freeging or fudden Change of Water into Ice,
gives the heft Idea, how Cryftal, Gems, amp;c. may be form'4
and that too perhaps in a very fudden ivianner.

Death : and animal dead Bodies frozen be-
come as hard as Stone. Hence it appear^,-
that freezing is not the Refult merely of the
Abfence of Heat, but is really owing to
fome active and penetrating material Prin-
ciples, which by mixing with other Bodies
become thereby fixt: and the Exiftence of
fuch Principles in the Air is farther appa-
rent from the rafting of Metals, the Erofion
of Stone, Glafs, amp;c.

The Sappofition that Salt-Petre is com-
pounded in a great Meafure of this fame vola-
tile acid Spirit exifting in the Air, is ftrength-
ened, not only by the Manner of its Pro-
duftion, but alfo from its ftriking the
Tongue, when tafted, with a pungent Sen-
fation of Cold, like what this fame Spirit
in the Air gives : Moreover, a volatile acid
Spirit may be obtained from it in confider-
able Quantity, whofe Particles are fo active
and powerful, that they penetrate, disjoin,
and feparate the component Particles of all
Metals except Gold, as well as Stones and
moft other Bodies.

Suppofing fuch Spirit one of the chief
Principles of Salt-Pkre, may not its exceed-
ing Volatility, when fuddenly and violent-
ly excited to Adion, by the Fire contained
in Sulphur kindled by Charcoal, produce all
the prodigious Effeds of Gunpowder * ?

and alfo by certain Mixtures in the Air,
become the Caufe of Thunder, Lightning,
and other wonderful Pha;nomena ?

The foregoing Conjeftures, into which
I fear I have been led too far by my Sub-
jeft, may it is hoped be forgiven, as they
are fubmitted entirely to the Confideration
cf better Judges, without the leaft Defign
of impofing them on any one.—But to re-
turn to the known Properties of Salt-
Petre.

It is faid to be the only Diffolvent of Sil-
ver, as Sea-Salt is of Gold : for Silver is dif-
folveable in no Menftruum yet known,
unlefs there be Nitre in it; and yet if Salt
be added thereto, the Mixture will no
longer diffolve Silver but Gold. It pre-
ferves the Flefh of Animals from Putre-
fadtion as well as S^a-Salt, and has the fin-
gular Property of giving it a red Colour
In Diftillation alfo, the Fumes that arife
from Nitre are red,

* The Roots of Madder mixed with the Food of Animals
tinges their Bones of a curious Red. Vide Phihfoph. Tranf.
In!» 442, and 443, where Experiments in Proof thereof ate
given by Mr. Belcher, F. R. S. The fame is likewife con-
firmed N° 457, by farther Experiments made by MonJ,
Du Hamei du Mmceau.

ing univerfally in the Air, and pervading
the whole terraqueous Globe. This, they
tell us, is an uniform Matter, or firft Prin-
ciple, diftributed every where throughout
the Earth aiid Atmofphere; though of a
Nature fo extremely fubtile, that it never
becomes fenfible, unlefs compounded with
other Subftances; but incorporating rea-
dily with different Kinds of Matter, it com-
pofe s, they fay, therewith all the Variety
of Salts, Cryftals, Gems, Metals, and Mi-
nerals; the Colour, Figure, Solidity, and
other Properties whereof are owing to the
Difference of fuch Admixture.

This is fometimes called * the Sal Acidum
Foffile, at other Times the Vague Acid.
Compounded with Earth, and an oily Mat-
ter, it is thought to be the Bafis of Sulphury
of Alum with a cretaceous, and of Vitriol
With a metalline Subftance. It is alfo fup-
pofed to be the faline Part or Principle of
aH Salts, which Monf. Romberg reduces to
three Kinds only, viz. Nitre, Sea-Salt, and
Viiriol.nbsp;^

The Configurations and Cryilals of Vi-
triol vary according to its different Kinds :
and its Difference in Kind is fuppofed owing
to different Adrnixtures of the fame, or dif-
ferent metallic Matter, with that acid Salt
(or Spirit) which is the Bafis of all Kinds of
Vitriol, Thus, wdien Copper is diffolved
by and incorporated therewith, the Vitriol
produced is blue; v/hen Iron is the Metal,
the Vitriol is green; and Lead, Tin, or
Lapis Calaminaris mixed with Iron is ima-
gined to render the Vitriol white. There is
ftill farther Variety ; but Iron appears to
be a conflant and principal Ingredient in
the green and white, as Copper is in the
blue,

LL Vitriol of this Colour is fuppofed
jr ^ to receive its Teint from Copper;
the befl is produced in Hungary and the
Ifland of Cyprus.

A Drop of the Solution heated a little,
and examined as before mentioned, pro-
duces Cryfi;als round the Edges, very fhort

at the Beginning, but increafing gradually
as reprefented Plate II. (in the Drawing
called Blue Vitriol) at the Figures i, 2, 3,
v/hich denote their Difference of Form, and
the Progrefs of their Growth, Thefe cryf-
taline Shoots are folid, tranfparent, and
regular, and refletfl the Light very beauti-
fully from their poliflied Sides and Angles.
As the watery Part evaporates. Numbers
of long flender Bodies refembling Hairs
are feen here and there, fome lying Side
by Side, as it were in little Bundles (vid. 4.)
and others crolTrng one another, in fuch
manner as to feem all radiating from a
Center, and compofmg ftar-like Figures,
which fee at 5, 5. This Salt proceeds but
flowly, and requires fome Patience before
the Configurations begin to fhoot: which
they do at laft, and that towards the Middle
of the Drop moft commonly, after a very
pretty Fafhion, as at 6 ; and it is to be ob-
ferved, that here alfo the principal Lines
iffue from a Center. Any farther Defcrip-
tion of the Drawing feems unneceffary : but
it is remarkable, that none of the regular
Cryftals are found in this Way of Examina-
tion, though they are to be obtained in
good Plenty by the ufual Method of Eva-
poration,

One of thefe regular Cryftals, of the
Size they are commonly found in the Shops,
is reprefented by the two Figures A and B,

If a Piece of Iron be left for fome fhort
Time in a Solution of blue Vitriol, its Sur-
face will appear of a Copper Colour, and
is really covered with Particles of Copper,
either precipitated upon, or attracted by
the Iron, to which they firmly adhere, and
whofe Pores they feem to fill. This may
ferve to ihew after what manner fome
Springs of Water are able to perform what
is ufually called a Tranfmutation of Iron
into Copper; which indeed is nothing more
than a gradual Diflblution of the Iron, whofe
Place becomes as gradually fupplied, and
its Figure affumed by the minute Particles
of Copper floating in the faid Water: fo
that, although a Mafs of Copper may be
found, after a Length of Time, inftead of
a Mafs of Iron, there is no Tranfmuta-
tion in the Cafe. The whole Fa6t feems
only to imply, that the minute Particles of
Copper wherewith the Water is flored, be-
ing much fmaller than the Pores or Inter-
ftices between the Particles of Iron, do firft
of all get into and fill up the faid Interftices.
We have then a Mafs compounded of Iron
and Copper; but the Iron Parts thereof
becoming gradually corroded and wafhed
away by the Water (the mineral acid Salts
it contains rendering it a Menftruum there-
to) their Places are immediately occupied

by Particles of Copper, which the Water
brings along with it continually ;. and a
Body of Copper at length is fubftituted in
the room of the Iron that was corroded
and wafhed away. The Petrifaftion of all
Bodies that were originally of fome other
Subftance than what they now appear to be,
was probably produced after a like Manner •
for it feems highly improbable that any
Subftance whatever can, ftriftly fpeaking, be
converted into a Subftance of fome other
Kind, however Appearances may happen to
impofe upon us.

Dr. Brown informs us in his Travels, of
two vitriolic Springs, called the old and
the new Ziment, rifing from a Copper Mine
in Hungary, which in fourteen Days turn
Iron left in their Waters into Cooper, and
that too more pure, dudtile, and malle'^ble
than any Copper extraded from the Ore:
that he took out with his own Hands from
one of thefe Springs the Figure of an Heart,
which had been put thereinto eleven or
twelve Days before, and found it as per-
fect Copper as it had been Iron when put
in. Some, he adds, will not allow this
to be a Tranfmutation, but argue. That
the Waters being faturated with a Vitriol
of Copper, and finding a Body fo eafy to
receive it as Iron is, it infmuateth thereinto
lo tar as to divide and precipitate the Iron,

leaving its own Subftance inftead thereof quot;^.
And this moft certainly is the Fad:, though
the Dodtor feems to doubt it; the Purity of
the Copper may be brought in Proof, and
is not to be wondered at, for the minute
Particles thereof, that floated in the Water,
and were depofited in the Pores of the Iron,
muft neceflarily be lefs blended with fo-
reign Matter than any Copper in its Ore
can be.

There are Copper Mines in the County
of Wicklow in Ireland, called the Mines of
Crone Banom, or Corona Alba, on the North
Side of the River Arklow, where the \¥ater
raifed from the Mines, that ufed to run
away in Wafte, has lately been converted
to great Profit: for by placing Iron Bars
on Beams of Timber fixed for that pur-
pofe acrofs large Pits or Cifterns, (floored
with fmooth Flags and lined on the Sides
with Stone and Lime) through which the
Water runs, the Iron becomes incrufted
in a few Days with Particles of Copper :
which being fwept oftquot; from Time to Time,
and falling to the Bottom, are, when a
Quantity is colleded, taken thence, in
a fine brown Powder, confifting of Copper
and the Rufl: of Iron 5 which affords, when

fmel^d and purified, a rich Copper, lo f.
per Ton more valuable than what is ob-

This was difcovered, by obferving, that fome
iron Tools of the Workmen, which had
iallen accidentally into the Water, were after
a while incrufted with Copper.

A Chain of thefe Pits is already made,
each I o Feet in Length, 4 in Width, and 8
in JJepth: and as many more may be funk
y People pleafe, there being a continual
^upplyofWatertorun through them all.
1 iiey make ufe of foft Iron, which attrafts
tne Copper Particles beft, diflblves, mixes,
and participates with them in form of a
brown Duft. A Ton of Iron in Bars pro-
duces one Ton, nineteen Hundred, and two
garters of brown Duft; and each Ton of
Duft fmelted, afi^ords 16 Hundred Weight
of pi^e Copper. There are at prefent about
500 Tons of Iron in the Pits. A large Bar

N. B. Whilft the minute and invifible
^articles of Copper are floating at Liberty

in any Menftruum, they are ftrongly at-
trafled by Iron ; infoffiuch that if a Needle
or the Point of a Knife be held but for a few
Minutes in a Solution of blue Vitriol, or it
blue Vitriol be wetted and rubbed upon
Iron, it will prefently be cafed over with
Copper : and yet when thefe lame Particles
are colleaed into a Mafs cf Copper, there
feems no Attraction between that Mafs and
a Mafs of Iron, nor has the Magn'et any
fenfible Effed on Copper.nbsp;__

^ Copper affords a blue or a green Tinc-
ture, according to the Menftruum wherein
it is diffolved; and therefore is fuppofed to
fupply Colour to the Emerald, Sapphire,
Turquoife, Lafis. Lazuli, Lapis Armenus,
and moft other Stones and Minerals jhat
are either green or blue, as well_ as to
the Subjea we are at prefent treating ot.
The amazing Variety of Blues and Greens
deducible'from- this Metal, and the Chan-
ges of one. into, the other, are exceeding-
ly worth the-while of every curious _Per-
fon to fatisfy himfelf about by a Tram of
eafy Experiments;' the Way of making
which may be found innbsp;^Treatife

of Colour's, in Boerhaaves Chemiftry, as
tranflated by Dr. Shaw, Vol. II. page Sf,
, amp;c. and in H/7/'s Letter, printed at the End ot
his Theophrajlus, on the EffeBs oj difierent
UenfiruumsonCopper-, where we areinformed,
that, of the Mineral Acids, Spirit of Sea-Salt,

Spirit of Nitre, and Aqua Regia, produce
with this Metal different Kinds of Green :
Oil of Vitriol, Oil of Sulphur, and Aqua
Fortis, different Degrees of Blue: that,
amongfl the vegetable Acids, diftilled Vi-
negar, Juice of Lemon, and Spirit of Ver-
digreafe (which is a Vinegar abforbed by
Copper) afford different Greens: that, of
the fix'd Alkalies, the Salt of V/ormwood,
Pot Afhes, and Oil of Tartar per deliquium,
give all a deep and delightful Blue; as do
alfo, among the volatile Alkalies, Spirit of
Sal Armoniac, Spirit of Urine, and Spirit of
Hartfliorn : that, of the neutral Salts, crude
Sal Armoniac produces a fine Blue-, na-
tive Borax a deep, and Sea-Salt a Whitijh'
Greejt.

quot; A Solution of Copper in any of the
beforementioned Acids, fo weak as
to leave the Menflruum colourlefs like
Water, may in an Inftant, by the Af-
fufion of a few Drops of Oil of Tar-
tar per deliquium, be converted into a
glorbus Blue, or by a like Quantity of
Spirit of Nitre into a beautiful Green:
nay, by this means made Blue, may be
yet changed into Green by a larger Quan-
tity of the Acid : and even when thus
made Green, again converted into its for-
mer Blue, by a yet larger Quantity of the
Alkali.

The blue Tindures of Copper made
in the fix'd Alkalies, may alfo be di-
G 2nbsp;quot; vefted

vefted of their Colour, and rendered co-
quot; lourlefs and pellucid like Water by Acids,
quot; if the Proportions be carefully regarded.
quot; The blue Liquor here is made colourlefsy
as the colourlefs Liquor was before made
Blue ; and the pellucid Liquor thus pro-
duced, will exhibit all the Phaenomena
before defcribed in that originally colour-
lefs. To this it may be added, that even
the ftrong blue and green Solutions are ea-
fily changed from Blue to Green, and from
Green to Blue in the fame Manner * quot;.
And how far Copper can difFufe its
Tindure (or its Parts become divifible)
may be learned from Mr. Boyle, who found
a fingle Grain of Copper, diflblved in Spirit
of Sal Ammoniac, would make 256806
times its own Bulk of clear Water of a blue
Colour; would give a manifeft Tinfture to
above 385200, and a faint, yet diftinguifh-
able one, to more than 530620 times its own
Bulk f.

OU R Green Vitriol contains a great
deal of Iron, but appears not to hold
any Copper, which makes its Colour difii-

■» Hill's rheophraftus, page 188, 189.
t Vide Boyle Abridged, Vol. I. page 408.

cult to account for : fmce all mineral Sub-
ftances, whofe Colour is. blue or green, have
been generally fuppofed to derive their Co-
lour from Copper.

When diffolved in Water, it conftantly
drops to the Bottom a yellow ferrugi-
nous Sediment; which being taken away,
the remaming Liquor, after a due Time of
Keft, affords Cryftals much clearer and of
a finer Green than the Vitriol was at firft.
Ihele hemg diffolved again throw down
another yellowifti Sediment, but in much
leis Quantity than before, and when cry-
tahzed anew appear of a ftill more live-
ly Colour. And by repeating this Opera-
tion, they may be rendered perfedtly tranf-
parent and of a delightful Green; tho'
after all fome Iron will ftill be left, which
fubjedls them to contradt a Ruft, if expofed
to the open Air,

A Drop of the Solution, moderately heat-
ed, and applied to the Microfcope, be-
gins to cryftalize about the Edges, and

Pquot;^ fuddenly and
lialtily, towards the Middle, in the Man-
ner represented by Figure 4, which begins
at and thrufts forwards and fideways
at he fame Inftant, with wonderful oX
and Regularity, to the other Extremity b,

where the whole Procefs is at an End. Its
regular Cryftals are rarely found in this Ex-
amination, but a Couple of them, as obtain-
ed by diflblving a Lump of our Subjeft in
boiling Water, and leaving it at Reft for
a Day or two, are placed at the Side of
the Drop. The firft of them A, is one out
of a great many that were formed on the
Side of the Glafs wherein the Solution ftood,
and adhered thereto. Thefe being pro-
duced in the clear Part of the Liquor, above
the ferruginous thick Sediment which
had been precipitated but was not taken
away, were much greener and more tranf-
parent than the Vitriol firft diflblved. Ex-
cepting fome Irregularities, they were all of
the fame Shape, with Sides nearly corre-
fponding.

The Figure B reprefents an Oftaedron,
that being the general Shape of many Cry-
ftals formed in the yellow thick Sediment
at the Bottom, a Fortnight or three Weeks
after, the clearer Part of the Liquor having
been poured away: and confequently the
Difference of Figure between this and the
former muft be imputed to the much
greater Proportion of Iron in this than
that.

Our green Vitriol, or Englifti Copperas,
is made from the Pyrita, that are found
in great Abundance on the Shores of Suf-
Jex, Efex, Kent, amp;c. Thefe Bodies are

of a ponderous and compad Subftance, con-
tain Metal and Sulphur, have a rully fer-
ruginous Outfide, but internally appear,
when broken, fometimes of the Colour of
Brafs, Silvery fometimes, and fometimes like
Iron; the Matter compofing them is dif-
pofed in Strise, or a linear Dirdion di-
verging from a central Point to the Cir-
cumference, if the Stones have any thing
of a circular or cylindric Figure ; or lying
parallel and perpendicular to the flat Sides,
if their Form be flattifh. After being
long expofed in Heaps to the Air and
Rain, the Salts begin to ad, vitriolic Ef-
florefcences pufli out upon the Surface,
they become brittle, fall to Pieces, and
diffolve into a Liquor. This Liquor, when
boiled two or three Days in a leaden Caul-
dron, (Pieces of Iron being thrown in from
Time to Time during the boiling and dif-
folving in the faid Liquor) is dilpofed af-
terwards in convenient Velfels, where it
ftands for about a Fortnight to cryftalize
into Vitriol. A great Work of this Kind
is, or was not long ago, carried on at
Deptford.

rr^.HE White Vitriol from Gojlar in
Jl Germany, as well as that from Hun-
gary, contains fome little Copper, but the
common Sort with us has no other Metal
in it befides Iron, unlefs, as fome fup-
pofe, there is alfo a fmall Quantity of Lead
or Tin. The Iron contained in the Greeii
and White, as well as the Copper in the
Blue, is not in any conftant Proportion, but
frequently more or lefs in different Pieces of
the fame Parcel, which occafions fome Va-
riety in Experiments made therewith.

A Drop of the Solution of white Vi-
triol begins to fliioot at the Edges, by a
gentle Degree of Heat, either in fmall an-
gular Figures, or minute curvilinear Spi-
culse, both which are reprefented in Plate
II. at i, i. The former of thefe fpread-
ing confiderably in Breadth, and protrud-
ing very flowly forwards, produce thofe
lineated Figures ftiewn at 2 on one Side
of the Drop, which are formed by two
Planes inclining to one another in an An-
gle of about 120 Degrees: the latter, viz.
the Spicules, fpreading likewife and flat-
tening at the Ends, ftiew themfelves nearly
as reprefented by 2 on the contrary Side.

Some of them however fhoot farther into
the Drop, in the Manner fhewn at 3, 4,
and 5 : and many fo (hot out have other
fmaller ones protruded from their Sides,
parallel to one another, and forming an
Angle with their main Stem of about 60 De-
grees, as at a, a : when the Procefs is nearly
over, many extremely minute Spicula arife
in the Interfpaces; fome uniting in, or ra-
ther fhooting from Centers, and making
a very pretty f radiated Appearance, like
what was. before obferved in the Blue Vi-
triol ; whilfl others of the fame Spiculce are
feen fcattered and difperfed about the Drop
in all Direitions, as at 8. Thefe Spicula
may be termed a Charadteriftic of the Vi-
triols, being ufually found in all of them,
when examined by the Microfcope w4th
Care; but as fometimes the Green is feen
without them, I have taken no Notice of
them there.

The Figure fliewn at 6 is feldom to be
met with, but when the Fluid Part of the
Drop is fuifered to evaporate without any
Heat; and it feems nearly to approach the
regular Cryfials, which are next to be de-
fcribed.

As a Solution of our prefent Subjedl does
not fo eafily cryftalize by the common

t It is obfervabie. that many of the Pyrita exhibit
L^nes diverging from a Center, exadlly in the fame Man-

Methods, after trying feveral Times to make
it do fo without Succefs, I have contented
myfelf with examining the * Gilla or Sal
Vitrioli made by the Chemifts: two Figures
whereof, A B, as magnified above a thoufand
times in the Area, are given at the Side
of the Drop. They appear to be qua-
drilateral Columns, the Inclination of whofe
Sides is oblique, having generally a qua-
drilateral Pyramid at each End, formed of
triangular Sides correfponding to thofe of
the Column, as at A; but fometimes thefe
triangular Planes interfedt, in fuch a Man-
ner that the Angle at the Apex is com-
prehended under only three of them, as
at B.

Vitriol in confiderable Abundance is found
in Subftance and of difiquot;erent Colours,
blue, green, white, and red, in feveral
Parts of Hungary, Germany, and other
Countries : but very little, if any, native
Vitriol is ever found in Mafles or Lumps
in England-, ail produced here being ob-
tained by Art from the Pyritce, and of the
white the greateft Part comes to us from
Abroad. The Appearance of fuch White
Vitriol is extremely like Loaf Sugar; it has a
fweetilh difagreeable ftiptic Tafte, and when

* Thefe Salts or Cryftals are obtained by the Help of
Spirit of Vitriol, or, asnbsp;direds, by diflblving White

It would be endlefs to enumerate all
the Ufes of Vitriol. Sir Kenehne Digby's
fympathetic Powder, fo famous in its Day
for the Cure of Wounds, v/as nothing elie
but Vitriol expofed to the Summer's Sun
for feveral Days and powdered. But a-
mongft all the reft, its being an Ingredient
abfolutely neceffary for the making of Ink
is not the leaft to -be regarded. Any
Vitriol that contains Iron will ferve to
this Purpofe, of what Colour foever it be :
the Green however is commonly preferred,
as holding a greater Quantity of that
Metal: but the White fometimes is not
lefs ftocked with it, and then will do full
as well. Galls unripe, or gathered when
they are of a blueifti Colour, before they
come to their full Growth, being beaten
to Powder, and infufed in Water, give the
Water a ftiptic Tafte, without altering its
Colour much ; but a proportionable Quan-
tity of powdered Vitriol, or a Solution of
Vitriol, being mixed therewith, turns it in-
ftantly as black as Ink, and wants only
a little Gum to make it Ink indeed.
A Decodlion of the dried Leaves of red
Rofes, of Sage, Oak Leaves, or the Rinds
of Pomegranates, produces the fame Ap-
pearance therewith. It alfo in like Man-
ner blackens an Infufion of Green Tea;

and therefore a few Tea Leaves put to
fteep for fome Minutes in any Mineral
Water made hot, will readily difcover if
it contains Vitriol, by fuch its Change of
Colour : the Proportion of the Vitriol may
likewife be gueffed at by the Deepnefs or
Palenefs of the Tindure.

On writing with a Solution of Green
Vitriol, nothing is feen upon the Paper
when dry: but by rubbing it over with
a Decodlion of Galls, what was written
becomes black and legible. Spirit of Vi-
triol wiped gently upon this, makes it
vani£h again immediately : Oil of Tartar
per deliquium reftores the Letters once more,
though not black but yellowifh -f-.

A ftrong Decodion of red Rofes mixed
with a Solution of Vitriol produces a black
Ink, which on dropping Spirit of Nitre
into it becomes inftantly red, and is far-
ther convertible into a greyifti Liquor, by
adding a little of th? volatile Spirit of Sal
Armoniac.

Good Writing Ink being not always or
every where to be procured, it will not
perhaps be unacceptable to give here an
eafy Way of making it, which I can re-
commend from many Years Experience.

Galls bruifed, two Ounces of green Vitriol
or Copperas, and two Ounces of Gum Ara-
bic grofly powdered. Let the Mixture be
well fhaken or ftirr'd about now and then,
and in twenty-four Hours it will be fit
for Ufe. It is moft conveniently made in
a wide-mouthed Bottle that will hold near
double the Quantity, where it may fome-
times be ftiaken together brifkly; but be
fure you let it fettle again before you pour
any off. When you have ufed all that
can be got off clear, a little more than half
the Quantity of the fame Ingredients will
make you another Quart.

What is written with this Ink looks pale
at firft, but after a few hours becomes of a
fine black, and I believe will never change.

VERDIGREASE is a blueifh green
Efflorefcence ¹ or Ruft, produced
on Plates of Copper, by corroding the
Surface thereof with that penetrating
Spirit which the Hulks of Grapes
abound with after they have been prelVd
and laid together to ferment. This Rufl

being digefted with diftilled Vinegar ni
a confiderable Degree of Heat, and dif-
folving partly therein, aifords a Liquor of a
moft beautiful green Colour, which after
Evaporation, being fet in a cold Place, pro-
duces tranfparent and elegant green Cryftals,
that are called ufually by the Name of
Dijiilled Verdigreaje, but are really a Vitriol
loaded with the pureft Particles of the
Copper.

If thefe Cryftals are diflblved in, warm
Water, and a Drop of it be applied to the
Microfcope immediately, it ufually produces
Abundance of the regular Figures i, 2, 3, 4,
5, 6, 7, (exhibited at the Side of the fourth
Drawing, Plate 11.) without forming any
confiderable Configuration: but if the
Solution is fuffei-ed to ftand quiet for a
few Hours, and a Drop of it be heated over
the Fire on a Slip of Glafs, till it begins to
concrete about the Sides, and then examined,
ftiarp-pointed folid Figures (bifeCted by a
Line through the Middle, from which they
are cut away towards the Edges) will be feen,
flaooting forwards, as reprefented i, i, i :
which Figures are oftentimes ftriated very
prettily from the Middle Line to the Edges,
obliquely, as 2, 2, may ferve to Ihew. They
both arife frequently in Clufters, and flioot-
ing from a Center, as at 3, 3.

fo, feveral regular Cryftals appear forming
in different Parts of the Drop, of the moil
lovely Emerald Colour, and reflefting the
Light from their Sides and Angles, which
are as exadly difpofed and finely poliflied as
if they had been cut by the moft fkilful
Jeweller. Thefe Cryflals are fliewn in the
Drop at 4, 4, but much better, becaufe
magnified a great deal more, at the Side of
it, by the Figures i, 2, 3, 4, 5, 6, 7.

No Configurations form themfelves in the
Middle of the Drop till the Fluid be nearly
evaporated, but when they begin to form
they proceed fomewhat haflily, and there-
fore mufl be attended clofely. Their com-
mon Figure refembles two long /y^ crofling
each other in an Angle of about 60 De-
grees, and fhooting Branches every Way:
each of which again protrudes other Bran-
ches from one, and fometimes both its Sides,
making together an Appearance like four
Leaves of Fern conjoined by their Stalks,
as at 5, 5. Separate Clufirers of the fame
fharp-pointed Figures, as thofe at the Edges
of t le Drop, are formed alfo frequently in
the Middle of it, as 6. Sometimes alfo they
put on another Form like the Leaves of
Dandelion, as at 7. Very beautiful Figures
are likewife produced by a Kind of Combi-
nation of fharp Points and Branches, in the
Manner reprefented 8, 8.

All the beforementioned appear of a mofl
lovely green Colour, but deeper or paler
according to the Time of their Produftion ;
the firft produced being conftantly the
deepeft. Towards the End of the Procefs
fome circular Figures are formed, extreme-
ly thin, and fo llightly tinged with green
xhat they are almoft colourlefs, but with
Lines radiating from a Center to the Cir-
cumference, like the ftar-like Figures of
Alum hereafter to be defcribed. Thefe are
fliewn 9, 9. When all feems in a Manner
over. Bundles of Hair-like Bodies appear fre-
quently fcattered here and there through-
out the Drop, in the fame Manner as de-
fcribed in the blue and white Vitriols.

f I'^HE Configurations of this Salt abound
J^ with Beauty and Variety, and prove
more or lefs perfeft according to the Strength
of the Solution, and the Degree of Heat
employed in making the Experiment to
judge of which a little Experience will be
found needful.

The Solution, however fated with Alum,
will not be found over-ftrong after ftanding

fome Days, for in that Time it will have
precipitated many Cryftals to the Bottom,
whereby the Liquor is fometimes left too
weak for our Purpofe; but then, by holding
the Phial over or near a Fire, the Cryftals
• will again diffolve, and be taken up a-new
into the Fluid. 'Tis not however advife-
able to make ufe of it as foon as this is done,
unlefs we v/ant to produce nothing elfe
but Cryftals : for if, after this, it be em-
ployed before it has had a little Time to
cool and fettle, it is very apt to form into
Cryftals only: but when it has ftood about
half an Hour, a Drop, placed on a Slip of
Glafs and heated properly, exhibits com,
monly at the beginning a dark Cloud, which
appears in Motion fomewhere near the
Edge, and runs pretty fwiftly both to the
Left^ and Right, until it is either ftopped
by the Intervention of fome regular Cry-
ftals, or elfe proceeds onwards both Ways
at once, and nearly of the fame Height,
till having furrounded the whole Drop the
two Ends rufh together and join ; the Pro-
grefs towards which is attempted to be
fliewn, P/^/^ III. Nquot; I.

. This cloudy Part of the Drop, that feems
violently agitated whilft it is running round,
appears on a ftnd; Examination to confift of
i^alts fhot into long and very flender Line.,
much finer than the fmalleft Hair, which
crofs one another at right Angles, and Fornx-
ol.ilnbsp;H

as they go along, from their internal Edges,
Rows of folid Cryftals compofed of many
oblique plain Sides b b, and which have
all a Tendency towards the Figures of
the regular Cryftals to be defcribed pre-

^^quot;fiut it happens frequently, that in fome
Parts of the Drop many minute and circu-
lar Figures are feen, rifing at fome little
Diftances from the Edge, whilft the above-
mentioned Operations are performing in
other Places thereof; which minute Figures
enlarging themfelves continually, appear at
laft of a ftar-like Form, or with Lines radi-
ating and diverging from a Center, in the

After the Bufinefs is over about the Edges,
a good deal of Patience will be requifite to
wait for the Configurations in the Middle
of the Drop, which feldom begin till the
Fluid feems almoft wholly evaporated; when
on a fudden many ftrait Lines appear puftiing
forwards, whofe Sides or Edges are jagged,
and from which other fimilar ftrait and
lagged Lines ftioot out at right Angles with
the'^firft) thefe again have other fmall ones
of the fame Kind ftiooting likewife from
themfelves, and compofe altogether a moft
beautiful and elegant Configuration, the
Order of which is attempted to be ftiewn

Each of thefe Lines increafing in Breadth
towards its End, appears fomewhat club-
headed, ^^e ee.

Sometimes inftead of fending Branches
from their Sides, many of thefe Lines rife
parallel to each other, refembling' a Kind of
Palifadoe, and having numberlefs minute
tranfverfe Lines running between them, as
at F.

But the moft wonderful Part of all, tho'
not produceable without an exadt Degree
of Heat and right Management, is the dark
Ground-work ftiewn at G, which confifts of
an almoft Infinity of parallel Lines, having
others crofting them at right Angles, and
producing a Variety fcarce conceivable from
Lines difpofed in no other Manner: the
Diredion of the Lines (which are exqui-
fitely ftrait and delicate) being fo frequently
and differently counter-changed, that one
would think it the Refult of long Study and
Contrivance.

During the Time this Ground-work is
forming, certain lucid Points prefent them-
felves to view (on one Side thereof moft
commonly) which Points grow larger con-
tinually, with Radiations from a Center,
and become Star-like Figures, in the Man-
ner of thofe before mentioned. Several of
them likewife flioot out long Tails, which
give them the Appearance of Comets : and
at the End of all, a dark Lineation, in
H 2nbsp;various

various Direftions, darts frequently through,
and occupies all or moft of the Spaces be-
tween them, making thereby no ill Repre-
fentation, when viewed by Candle-Light,
of a Night-Sky, illuminated with ftiining
Stars and tailed Comets, and rendering
the whole Scene extremely vvhimfical and
pretty.

Nor do thefe Configurations break away,
or diffolve, foon after their being form-
ed, as many others do; but may be pre-
ferved on the Glafs in good Perfedion for
Weeks or Months, if Care be taken neither
to exclude the Air wholly from them, nor
put them in a moift Place : for in either
Cafe they will be foon deftroyed.

Being deflrous to preferve fome exceeding
fine Star and Comet-like Figures, I faften-
ed another Glafs of its own Size upon the
Slip where they were formed ; having firft
placed thin Pieces of Cork between, to pre-
vent the Glafles from touching, and after
all ftopped the Ends and Sides with Sealing
Wax, thereby to keep out the Air, which
I imagined would fpoil them : but contrary
to my Expedation, in two Days the Figures
were all obliterated; whereas another Con-
figuration, covered with a Slip of Glafs to
preferve it from being touched, but whofe
Sides were open to the Air, continued in
great Perfedion at leaft two Years, and then
too was fpoilcd by Accident.

how to produce andpreferve. loi
The fame Thing likewife happens to
Saccharum Saturni, Ens Veneris, Salt of Am-
ber, and fome other faline Subftances, whofe
elegant Configurations may be long preferv-
ed between Slips of Glafs kept afunder as
above direCted, provided the Air be not pent
up with them, and that the Place you put
them in be dry. I have at this Time feve-
ral Configurations formed fom^e Years ago ;
and it will fave much Trouble, and be moft
agreeable to People not overfl:ock'd with.
Patience, to have always as many kinds as
one can thus ready, to fliew fuch Friends
whofe Curiofity may not be fufhcient
to make them attend to the whole Pro-
cefs.

A great deal of ExaClnefs and Nicety is
requifite as to the Degree of Heat, to make
one and the fame Drop produce all the Con-
figurations prefented in the Plate ; tho' you
will certainly meet with feveral of them in
every Drop you try, unlefs the Heat be too
long continued; in which Cafe the Fluid
becomes hardened by the Fire into a kind
of tranfparent Gluten, which never flioots
at all, is not ealily diflblveable, or to begot
off the Glafs without fome Pains. On the
other hand, if the Heat be violent, though
not long, it fhoots too fail, with much Ir-
regularity and Confufion.

The regular Cryftals are often formed in
the fame Drop with the other Configura-
tions, as at ƒ. But if not, they may eafily
be produced, either by ufing a Solution
made with hot Water, before it cools; or
by placing a Drop of a well-faturated Solu-
tion, when cold, on a Slip of Glafs, and
fufferihg the Fluid to evaporate without
any Heat at all. Cryftals will alfo be form-
ed by Precipitation after the Solution has
ftood fome Time.

After numberlefs Obfervations to deter-
mine the Cryftals of Alwn, I find amongft

Some are exadly regular 06taedra, com-
pofed of eight equilateral Triangles, as the
Figure A.

But as they lie moft frequently on one of
their triangular Bafes, they appear in the

folid Angles cut off, forming thereby a
Figure of fourteen Sides, eight of which
are Hexagons, and the other fix Squares,
as C.

The Figure D frequently prefents itfelf,
and feems dfo compofed of fourteen Planes
(viz. 12 quadrilateral, and two hexagonal)
the Planes underneath being fuppofed to
correfpond in Number and Figure with
thofe that appear above.

E reprefents an eight-fided Figure, con-
fifting of two triangular, two hexagonal,
and four quadrilateral Planes, two whereof
flope downwards from the upper hexangular
Plane, and the other two upwards from the
under one.

The Figure at F is compounded of eight
Planes, the undermoft whereof is a large
equilateral Triangle, from each Side of which
afloping quadrilateral Plane proceeds. Thefe
Planes are Trapezoids, each of them having
a Side in common with that of the Triangle,
another ftiorter one parallel thereto, and two
others floping one towards the other, and
towards t ae Side of the Triangle, in a Di-
rection of about twenty Degrees.

The Plane which lies parallel to the
Triangle (which Plane in the prefent Fi-
gure is next the Eye) is hexagonal, three
of its Sides being made up of the fhorter
parallel Sides of the Trapezia : the other
three (which are lefs than thefe, being cut
down perpendicularly, fo as to meet the
Angles of the large Triangle) form three
other fmaller Triangles, each whereof has
one Side in common with the Hexagon,
and the other two with the neighbouring

Our Alum is obtained from a blueifti mi-
neral Subftance refembling Slate, which
after being calcined and fl:eeped in Water

for a due Time, that Water when boiled
fuffieiently in Pans of Lead (the Lees of Sea-
weed Afhes called Kelp, and the Quantity
of Urine being mixt therewith) produces
Shoots of Alum, after ftanding a few Days.
But as fuch Shoots are feldcm clean enough
at fixft for Sale, they coinmonly are wafo-
ed with or diflblved again in Water freed
from their Impurities, and fet to concrete
a-new.

Vaft Quantities are made in Torkjhire
and Lancajhire, moft of the Hills between
Scarborough and the River Tees, as well as
thofe near Frejion, abounding with this
Mineral; the Salts of which being diflTolved
and put into Aftion by the Moifture of the
Air, if thereto expofed, without being cal-
cin'd, the Mineral falls in Pieces, and yields
a Liquor whereof Copperas or green Vitriol
may be made

Alum may alfo be procured from certain
Earths by pretty much the fame Means.
An Earth of this Kind now lies before me,
which was brought from A.frica, where a
confiderable Trad of Land is faid to be of

• At Mtfettle in Bohan'ta are Mines of black SdiJIus,
whence they make great Quantities of Alum and Vitriol;
and from a Gkla Pyritofa found in the fame Mines, they
obtain much Sulphur. I am obliged to Dr. 'James Mouv/ey
for this Information ; and for Specimens of both the Sub-
ilances, which he ccllefted upon the Spot and fent roe.

the fame Sort It taftes exaftly like Alum,
and in the South Sea Year, 1720, a Quan-
tity was imported in Hopes of making it
turn to good Account: but the Mifchiefs
fuffered from other Projeds at that Time,
difcouraged People from embarking in thisj
and we have heard no more of it lince;
nor indeed, as Alum can be made fo cheap
from Materials found at Home, does it feem
worth \Vhile to fend fo far on the fame Ac-
count.

Alum feems fo nearly a-kin to Vitriol, that
the Addition of Copper or Iron is only want-
ing to make it the fame Thing; as may be
proved by a Diftillation of it into an acid
Spirit with either of them, whereby it be-
comes good Vitriol. On the other hand.
Vitriol, when freed from its metallic Parti-
cles, becomes aluminous, and yields on Dif-
tillation a Spirit undiftingui£hable by the
niceft Scrutiny from that of Alum -f.

• I have alfo an aluminous Earth brought from Maryland,
and given me by Mr. Brook.

Borax is a faline Subftance, very
difficult in Solution unlefs in boiling
Water, and even then requiring, accord-
ing to Boerhaave, twenty Times its own
Weight.

When a Drop is given to be examined by
the Microfcope, if it be held too long over
the Fire no Cryftals will flioot, but it will
harden upon the Slip into a tranfparent Mat-
ter much refembling Glafs. The beft Way
is to give it a briflc Heat for about one Second
of Time, and then applying it, the Cryftals
will quickly be feen forming about its Edges,
as in Plate III. Nquot; II. where their Begin-
ning and Progrefs are fo reprefented as to
need no farther Defcription.

In the middle Parts of the Drop no Cry-
ftals at all arife, but there are feveral tranf-
parent circular Figures, that from mere
Specks grow gradually bigger, till they re-
femble Imall Drops of Oil floating upon the
Surface of Water: thefe allfo are ftiewn in

This Salt is faid to be found in India,
Perfta, and Tartary, and to be brought
from thofe Countries rough and foul, in

Lumps or Cryftals, of a yellowifti and
fometimes of a dirty green Colour: but we
really know little thereof with Certainty.
The Venetians made great Profit heretofore
by purifying it for Sale but that Trade
at prefent is chiefly carried on by the Dutch;
though I am told the Secret is become
known, and has lately been praftifed with
good Succefs in England. It ferves the fame
Purpofes of fufing and foldering Gold and
other Metals, as the Chryfocolla of the An-
cients did, for which Reafon it is frequent-
ly called by the fame Name, though theirs
was quite another kind of Subftance, the
Knowledge whereof is probably loft to us..
Its glalTy Quality renders it ufeful in dying,
to give a Glofiinefs to Silks; and Dr. Shaw
proves (in the twentieth of his Chemical Lec-
tures, Experiment 3d.) that by means of
this Salt a Kind of Glafs may be made
of an extraordinary Degree of Hardnefs ; and
imagines the Arts of Enamelling, and of
imitating precious Stones, may be greatly
improved thereby -f.

* Vid. Siaws fraujlation of Boerhaa've's ChemiJIry, Vol. I.
p. no, in the Notes.nbsp;,

t Rough Borax is called Tincal, or Tincar. Geoffroy fays,
a fait, muddy, greenilh Water, found in fome Copper Mines,
evaporated to a certain Degree, then kept for feveral Month-i
in Pits, whofe Sides and Bottoms are plaiftered with the Mud
of the fame Mines mixt with Animal Fat, the Pits being alfo
covered with the fame Plaifter, produces the Lumps or Cry-
ftals of unrefined Borax.

When refined and pure it is brought in
large cryftaline Shoots clean and white,
about the Clearnefs and Hardnefs of Alum,
wherewith it is fometimes adulterated: to
the Tafle it is almofi: infipid, but fomewhat
fmooth and oily, and the more fo the lefs it
has been purified, for in its foul State 'tis
confiderably fat arid greafy.

A regular Cryftal of fuch purified Borax,
as taken by the Microfcope, is fhewn on the
Side of the Drop at A.

Some Years ago my worthy Friend Mr.
Feter Colinfon, F. R. S. favoured me with a
Subftance faid to be brought from Perfa,
and called Native Borax : 'tis in fmall, irre-
gular, flattifh Pieces, of a greyifh white Co-
lour, wherein, if nicely examined, abun-
dance of fhining Particles may be difcerned :
it is light and porous, of a very brittle
Confiftence, fomewhat urinous, and more
pungent in Tafte than the Kind before
defcribed. A Solution of this did not fhoot
at all into Cryftals, but in many Exami-
nations filled the whole Drop with figur'd
Bodies like that at B ; which, from being
barely vifible, enlarged pretty faft, to a
Size (when viewed by the fourth Magni-
fier) as big in Appearance as the Figure
here exhibited.

WHAT the Ancients called by this
Name, is fuppofed to have been
a Salt generated in the Earth or Sande,
from the Urine and Dung of Camels (made
ufe of by the Multitudes of Pilgrims that
reforted to the Temple of Jupiter Amnion)
which, being fublimed by the Sun, pro-
duced this Kind of Salt; and the Difufe of
that Cuflom for many Ages, is imagined to
be the Reafon why none of it is now found.
What we have at prefent is undoubtedly
factitious, being made of Urine, Sea-Salt,
and Soot. It is fuppofed to come from Egypt
or Syria, in round Cakes near three Inches
thick, and about half a Foot in Diameter :
in Colour it is greyifli on one Side, and
appearing, for the moft Part, black, or ra-
ther footy on the other. When broke, the
Infide (if good) is white, tranfparent, and
cryftaline, and in Appearance much like
Camphire. We are told, that in thofe
Countries they colleCt a Soot from the
burning of Camel's Dung, which they
fprinkle with a Solution of Salt made in
Urine of the fame Animal, and then fub-
iime in Glafs Veffels, till a Cake is thrown
up to the Top of each, correfpondent to
the Shape of the Glafs, which they muft

break in order to get it out.—All this may
perhaps be true, but I am apt to think it is
made much nearer home, and by more eafy
means.

Some of this Salt diffolved in Water, and
a Drop thereof placed on a Slip of Glafs,
to be examined by the Microfcope, will be
found to Ihoot with a fmall Degree of Heat j
which muft be very carefully obferved, for
if more Heat than juft enough be given
to it, the Configurations will run into one
another, and make the Whole appear in

It begins with ftiooting from the Edges
great Numbers of ftiarp, but thick and
broad Spicule, from whofe Sides are pro-
truded as they rife many others of the
fame Shape, but very fhort, parallel to each
other, but perpendicular to their main Stem,
as at i. Plate III. Nquot; III. Thefe Spicula
arrange themfelves in all Diredions, but
for the moft Part obliquely to the Plane
from whence they rife, and many are fre-
quently feen parallel to one another : which
Particulars the Figure endeavours to ex-
prefs at i, 1.'-As they continue to pufti

forwards (which they do without increaf-
jng much in Breadth) fome flioot from
them the fmall Spicules only, as at z.
Others, after they are nearly come to their
full Growth, divide into two Branches, in
a Manner different from all otli^r Kinds

of Salt I have ever feen, by the Splitting
of the Stem, longitudinally, from the Top
almoft to the Edges of the Drop, but with-
out any Shootings from the Infide, as is re-
prefented at 3.-Other Branches, befides

the fmall Spiculee mentioned above, protrude
longer ones of the fame Form, from whence
others alfo proceed : which others ftioot alfo
fmaller ones from them, and fo on to many
Gradations, as at 4.

Before the Middle of the Drop begins
to fhoot, feveral exceedingly minute Bodies
may be difcerned at the Bottom of the
Fluid. Thefe rife to the Top in a Httle
while, and as foon as their Form can be
diftinguiihed, whilft yet extremely fmall,
they plainly wear the fame Shape exad:ly,
which they afterwards appear in when grown

Growth is very quick, and pretty equal
for a Tim.e, but at length fome one Branch
gets as it were the Maftery, and fhooting
farther than the reft, forms the Figure
6. The other Branches enlarge but little
afterwards, all the Attradion feeming biafled
to this alone, from which more Branches
being protruded, and they again protrud-»
ing others, the whole appears like Fi-
gure 8.

'Tis not uncommon to fee in the Middle
of the Drop fome different Configurations,
where, inftead of the ftrait Stems defcribed

above, there is formed a Kind of Zigzag,
with Spicule? like thofe in the other Figures,
as at 7.

To obtain the Cryftals of this Salt, 'tis
neceftary to place a Drop of a frefti Solution
(made in warm Water) before the Micro-
fcope, without giving it any other Heat
than the Warmth of the Water. The re-
gular Cryftals will then appear as reprefent-
ed at the Side of the Drop A, B, C. The
laft of which Figures C is produced from
the fécond B, by new Formations at each
Corner of the crofs Branches, when the
whole Procefs is nearly ended : but thefe
Cryftals are rarely feen, unlefs the Solution
be examined as foon as made.

Salt Ammoniac is particularly remarkable
for rendering Water wherein it is diflblved
colder than any other Salt can do, and even
equal in Degree to Water that is near freez-
ing. Monfieur Geoffroy placed a common
Thermometer of eighteen Inches long in a
Phial wherein he had put a Pint of Water,
and let it remain therein a fufficient Time
to adjuft itfelf to the Temperature of the
Water : he then put into the Water four
Ounces of Salt Ammoniac, and in lefs than a
Quarter of an Hour the Liquor in the
Thermometer defcended two Inches and
nine Lines. He then tried the fame Expe-
riment with Salt-Petre inftead of Salt Am-
moniac, uflng the like Precautions, and the

Liquor defcended one Lich and three Lines,
Vitriol made it defcend not quite an Inch,
and Sea-Salt but two Lines.

Monfieur Romberg orders a Pound of
Salt Ammoniac and a Pound of corrofivc
Sublimate to be feparately reduced to Pow-
der ; then, after mixing them well together,
he direfts them to be put into a Glafs Bottle^
and a Pint and a half of diftilled Vinegar
to be poured thereon. This done, and the
Compofition being fhaken together brifkly,
it will become fo cold, that a Man can but
ill endure the Veifel in his Hands even in
the Summer-time. He fays, that once, as he
was making this Experiment, the Mixture
happened to freeze ; and Monfieur Geofroy
tells us the like Accident befel him once
on diflblving a large Quantity of Salt Ammol
niac m Water, fome Drops on the Outfide
of the Glafs freezing: the wet Straw where-
on it ftood, was likewife faftened thereto
by Ice. But though he try'd many times he
could never produce Ice again.

It is not my Purpofe to enumerate the
lèverai Ufes of this Salt ; I ihall therefore
conclude with obferving, that it is extreme-
ly pungent, converts Aqua Fortis into an
Agua Regia, caufes Tin to adhere to Iron,
and diflblved in common Water, is, I am
mformed, a Secret for fbe taking away of

This Salt, which from the Sweetnefs
of its Tafie is ufually called Sugar of
'Lead, is prepared from Cerufe or White Lead
digefled with diftilled Vinegar in a Sand
Heat to a Diflblution : then evaporated till a
Film arifes, and fet in a cold Place to cry-
ftalize. It is therefore Lead reduced into
the Form of a Salt by the Acid of Vinegar,
for Cerufe is itfelf nothing elfe but the
Ruft of Lead corroded by Vinegar,

A little of this Salt diffolved in hot Water,
which it immediately renders milky, after
Handing a Quarter of an Hour to fublide, is
in a fit Condition for an Examination by the
Microfcope. A Drop of it then applied on
a Slip of Glafs, and held over the Fire to
put the Particles in Adion, will be feen
forming round the Edge a pretty even and
regular Border, of a clear and tranfparent
Film or glewy Subftance (See Plate IV.
quot;^quot;l.aaaa.) which, if too fudden and
violent Heat be given, runs over the whole
Area of the Drop, and hardens, and fo
quot; fixes, on the Glafs, as not to be got off with-
out much' Difficulty. But if a moderate
Warmth be made ufe of (which likewife
muft not be too long continued) this Border
■ .nbsp;prpr

proceeds a litle Way only into the Drop,
with a Kind of radiated Figure compofed
of a Number of fine Lines, or rather
Bundles of Lines, beginning from Centers
m the interior Edge of the Border, and
fpreading out at nearly equal Diftances from
each other every Way towards the Exterior,
i b b b. However it is obfervable that
the Diftances between the Lines are filled
up with the glewy Matter, nor do the Lines
themfelves feem detached therefrom, but
are formed together with it. From thefe
fame Centers are produced afterwards a
-Radiation alfo inwards towards the Middle
of the Drop, compofed of Parallelograms
ot different Lengths and Breadths ; from one
and fometimes both the Angles whereof
there are frequently feen Shootings fo ex-
ceedingly flender, that they are perhaps the
beft Reprefentation pofTible of a mathema-
tical Linei which appear like a Prolonga-
tion of one or both the Sides. The Extre-
niities of thefe Parallelograms are moft
commonly cut off at right Angles, but they
are fometimes alfo feen obliqUe. The whole
ot this Defcription is fhewn zt c c c c.

Centers with the like Radii iffuing from
tliem, and fome of the glutinous Matter
ior ^eir Root, are fometimes formed in
the Drop, intirely detached from the Edges,
and m thefo it is very frequent to find a Sort
ot fecondary Radii proceeding from fome one

of the primary ones, and others from then;î
again to a great Number of Gradations,.
forming thereby a very pretty Figure, the
Reprefentation of which is given at D.

Give me Leave now to obferve, that ra-
diated Figures of Spar much refembhng
thefe, and which probably owe their Form
to the fame Principles, are fometimes found
in Lead-Mines, of which I have at this
Time a Specimen before me.

Notwithftanding it may feem wandering
from my Purpofe, I ftiould think myfelf
greatly wanting in my Duty towards Man-
kind, if I clofed this Chapter without warn-
ing them of the Mifehiefs that may arife
from taking this or any other Preparation
of Lead internally, as the poifonous Quali-
ties of that Metal are not to be fubdued or
cured, and thofe who have much to do with
it feldom fail fadly to experience its bad Ef-
fets. I am fenfible this Salt has frequent-
ly been prefcribed in Quinfies, Inflamma-
tions, and other Diforders where great
Cooling has been judged neceflary : But
Dr. Boerhaave declares he never knew it
given with Succefs, nor durft himfelf ever
prefcribe it internally, from his Knowledge
that there is fcarce a more deceitful and de-
ftrudive Poifon than this, which returns to
Cerufe as foon as the Acid is abforbed there-
from by any thing it may meet with : and
that it proves afterwards a m.oft. dangerous-

«hd incurable Poifon. Ccrufe, tlie fine white
Powder of Lead, drawn with the Breath into
the Lungs, occafions a moft violent and
mortal Afthma j fwallowed with the Spittle
it produces inveterate Diftempers in the
Vifcera, intolerable Paintings, Pains, Ob-
ftruftions, and at laft Death itfelf: which
terrible Effedts are feen daily amongft thofe
who work in Lead, but principally amongft
the White-Lead Makers

The Fumes of melted Lead are a Secret
with fome for the fixing of Quickfilver, and
rendering it fo folid that it may be caft into
Moulds ; and Images may be formed of it,
which when cold, are not only hard, but
fomewhat brittle, like Regtihts of jinti-
mony -f.

Salt of Tin is obtained in the fame
Manner as Salt of Lead, bv digefling
the calcined Metal in diftilled Vinegar, and
fetting it, when poured off, in a cool Place,
for the Salts to fhoot: which they will do
in the Form of Cubes.

• Boerhaarveh Chemifiry by Sba'vo, Vol. II. pag. 2
t Vid. Sherley on the Origin of Bodies, pag. iSf

This cubic Salt being diffolved in Water,
and a Drop of the Solution placed under
the Microfcope, in the Manner before di-
re6led, produces fuch an Appearance at
the Edges of the Drop a a reprefent,
confifting of Odaedra, partly tranfparent,
ftanding on long Necks, at fmall Diftances
from each other, with angular Shoots be-
tween them. At the fame time folid and
regular opake Cubes will be feen forming
themfelves in other Parts of the Drop, vid.
b b. Plate IV.

Thefe may be difcerned when their mag-
nified Size is extremely fmall j and their
Bulk increafes under the Eye, continually,
till the Water is nearly evaporated.

In the Midft of the fame Drop, and in
feveral Places thereof, very different Figures
will be likewife formed ; particularly great
Numbers of flat, thin, tranfparent, hexan-
gular Bodies, c c c, fome amongft which
are thicker, as e; and a few appear more
folid, and with fix floping Sides, rifing to
a Point as if cut and polifhed, vid. d.

The Figure ƒ is compofed of two high
Pyramids united at their Bafe *. Some, in
this kind of Form, are found truncated at
one of their Ends, and others at both;

• Dr. Wood-ward va. \ihHijl. ofFoJfih, Vol.1, p. 222, fays.
That Grains of Tin, and the Cryftals from it, in the Mines,
are quadrilateral Pyramids: and this feveral of them now
before me prove.

but_ then they appear Hke flat Bodies, not
having the four Sides of a Pyramid j as a
few of them in the Drawing 'fhew.—Seve-
ral of the hexagonal Bodies may be obferved
with floping Sides, forming a fmooth trian-
gular rifing Plane, whofe Angles point to
three intermediate Sides of the Hexagon,
Did. g: and fome have a double Triangle,
as another of the Figures fhews.—h repre-
fents one of the folid Cubes.

The. Drawings in this Plate fliew, that
notwithfl;anding the feeming Aflinity of the
two Metals, the Configurations of Salt of
Tin bear not the leaft Refemblance to thofe
of Salt of Lead. In convulfive and epi-
leptic Cafes, Salt of Tin is given internally
with good Succefs.

A S Chemifts give the Name of Venus
Copper, one would imagine their
Em Vfneris to be a Preparation of that Metal;
whereas it is in reality a Sublimation of the
Salt of Steel or Iron* with Sal Ammoniac-,

and therefore might be called Ens Marfis
with better Reafon. It muft however be
acknowledged, that blue Vitriol was em-
ployed formerly inftead of Salt of Steel;
and That, being impregnated with Copper^
rendered the Name lefs improper: but the
Ens Veneris our Shops afford at prefent, has
nothing of Copper in it.

It diffolves eafily in Water, and gives to
the Solution fated with it a Colour refem-
bling that of Mountain Wine : which Co-
lour its Cryftals likewife retaining, appear
(as they form before the Microfcope) like
the moft beautiful Chryfolites or Topazes,
feemingly cut with the greateft Elegance,
in Shape as the Plate fliews ; and reflecting
an extraordinary Luflre from their polifhed
Surfaces, if the Candle be fo fhifted as to
favour its being feen.

After the Solution has ftood an Hour or
two to fettle, (for if ufed immediately its
Foulnefs will prove inconvenient) a Drop
thereof placed on a Slip of Glafs, and warm-
ed a little over the Candle, begins fhooting
from the Edges with folid tranfparent An-
gles, as (in the Drawing) a a. ^ Plate IV.
'I'hefe, if only a gentle Heat has been given,
will fometimes form, then diflblve, and
afterwards form again.

The Cryftals b b within the Drop, and
underneath the fame i, 2, 3, 4, 5, 6, 7, are
likewife beft formed by a gentle Heat, and

may be difcovered in the Fluid, when their
magnified Appearance is no bigger than a
Pin's Point, gradually increafing every Mo-
ment with regular Sides and Angles, polifli-
ed Surfaces, and the Brightnefs of precious
Stones. If too violent an Heat be given,
inftead of fuch Cryfials, compound Figures
will be formed, very fuddenly, refembling
that at c, confifling of parallel fi:ralt Lines,
pointed with large folid Spear-like Heads
of Cryflal, along the Sides of which are
placed, at right Angles, great Numbers of
fmall Cryfbals of the like Shape as the
Drawing fhews.—If the Heat has been
little, though the fame Kind of Forms will
be prefented, they will not appear till the
Moiflure be nearly dried away, when they
will fhoot out with amazing Quicknefs.
Some fmaller Compofitions are alfo not
unufually feen, as at d.

But the Singularity of this Preparation is,
that in fome Part or other of the Drop, you
Will feldom fail to find a very regular and
well-fafhioned two-edged Sword of Cryflal,
forming under the Eye, in fuch Shape as e
reprefents, though more exadt and well-
proportioned : for fufpecling fuch a Figure
i^ight be fuppofed imaginary, lefs Regula-
rity has been defignedly given it, than it
Will be really found to have. Sometimes
two, three, or more, fuch cryflaline Swords
are feen in the fame Drop.

The regular Cryftals of this Subjed foon
lofe the Sharpnefs and Elegance of their
Form; but its compound Configurations,
whofe Beauty and Regularity are not to be
conceived from Defcription, though vi'hen
the Fluid is nearly evaporated they feem
blunted and indiftind, yet afterwards, when
the Moifture is quite gone, they recover
their former Appearance, and may be pre-
ferved a long while, by the Method before
direded, 36. Salt of Amber, and fome
other Salts, lofe and recover themfelves after
the fame Manner.

/quot;TT^ H E Flowers of Antimony are colleded
JL in Form of a white Powder, from
the Fumes of burning Antimony, by means
of a Glafs Veffel placed over it j and are
fuppofed to contain the moft adive Salts
and Sulphurs of that Mineral. The great-
eft Part of thefe Flowers, when they are
well ftirred about in Water, fink to the
Bottom thereof, leaving the.Salts difiTolved
and fufpended therein ; and on placing a
Drop of fuch Water on a Slip of Glafs, and
giving it a gentle Heat, Numbers of flender
1 onbsp;and

and extremely ffiarp-pointed Spicule will be
feen forming at the Edges of the Drop, as
Plate IV. a a a. At the fame time mi-
nute Particles of the Powder,quot; that were alfo
fufpended in the Fluid, will be brought
together by a mutual Attradlion, and unite
a little farther within the Drop, in Confi-
gurations refembling a fine Mofs or Coral-
line, very beautiful and curious to be-
hold : uid. b -The Middle of the Drop
ufually remains clear and void of every
thing.

Antimony (the Stibium of the Ancients)
is found in many Countries : it is compofed
of glittering, brittle Strict like Needles, the
Colour of poliflied Steel; fometimes run-
ning parallel to each other, and fometimes
lying in different Diredlions.—If taken as a
?»ledicine in its native Condition, it is fup-
pofed very harmlefs, occafioning no fenfible
Diforder in the Body: but, after the Che-
mift has tried his Art upon it, it becomes
capable of purging or vomiting with great
Violence, even in a very fmall Quantity, and
therefore fhould be adminiflered with much
Caution. Its Operation is however extreme-
ly uncertain; the fame Dofe at fome Times
feeming to have no Effect at all, which
at other Times will operate upwards and
downwards in fuch Manner as to threaten the
Patient's Life. This makes moft Phyficians
afraid to meddle with the more elaborate

Prepafations of it j though 'tis generally
knowiedged, that if the Manner of theiif
Operation was certain, or their Violencö
could be fufficiently reftrained, great Cures
might be expelled from them. Several
Nojlrurm, exhibited in very fniall Dofes,
tinder different Forms, and cried up as al-
moft univerfal Remedies, are believed, not
without Probability, to be Preparations of
this Mineral; from the like Uncertainty iii
their Operation, and the Violence where^
with they fonietimes aft.

As this Uncertainty is too notorious to
fee denied, the Difpenfers of thefe Medi-
eines plead, that the Manner of their Ope-
ration depends entirely on the Conftitution
and Diftemper of the Patient, but always
tends to produce a Cure : for, fay they, if
vomiting be moft neceffary, the Medicine
will prove emetic, and that juft fo long
and with fuch a Degree of Force as is
fequifite to bring away the morbid Mat-
ter; on the contrary, if purging be moré
conducive to a Cure, the morbid Matter
will be carried downwards; and if the
Difeafe requires neither purging nor vo-
miting, neither will be excited, but the
Diforder will be cured by Perfpiration or
fome other infenfible Way.—The Truth
of this I have nothing at all td do with,
but refer the Confideration of it to thofe
to whom it more properly belongs : per-
mit

tnit me only to obferve, that whatever
Drug can operate as this does, muft be
capable of producing great Good or Harm
in animal Bodies, according as its Powers
can or cannot be diredted or regulated: and
confequently, whoever can difcover Means
to corredl its Violence, and render it a per-
fe(5tly fafe Medicine, will deferve greatly of
Mankind.

I fhall conclude this Head with taking
Notice, that the Star-like Shootings on the
Regulus of Antimony, about which fome
Chemifts make much ado, are nothing more
than the natural Configurations of its
Saltsnbsp;-nbsp;,

Mercury, purified Nitre, (or the
Spirit of it) calcined Vitriol, and
Sea-falt, are the Ingredients from which
Gorrofi-ce Sublimate, or Mercury Sublimate, is'
prepared; which is one of the moft violent

* Regulus of Antimsny made up in a proper Perm and
r f nnbsp;PtrMual Pill, becaufe it receives very

Diminution, tho' carried through the Stomach and
»owels fifty timei, and will purge every time take it
as onen as you pleafe. Antimomd C»ps are made jifccs,
e cf this Regulus, which for a iQng Time will render

and deadly Poifons we know, lacerating and
excoriating the Vifcera, by its keen and
adive Spiculse, till a pangrene and Death
enfue ; unlefe- proper. Remedies are immedi-;
ately :ufed to prevent it. ; .

A Drop of the Solution of this Subli-
mate in Water, appears by the Microfcope
to begin fnooting froin the Edges, as at
a, Plate IV. immediately after which, dilFe-.
rent fhaped Bodies are feen pufliing onward
towards the Middle,; fome quite ftrait and:
extremely ftiarp like the Points of Needles,
others widening: themfelves towards their
Extremities,, and bending in fuch Manner
as to refembls Razors with keen Edges:
amongft thefe many are jagged and in-
dented like Saws, fome on one Side only,quot;
and fome on both Sides ; all which Par-
ticulars I hope the Drawing will render
intelligible, vid, b b. Thofe that widen
towards their Ends, ftop their Progrefs,
when advanced to the Condition reprefent-
ed : but fuch as are ftrait and tapering to a
Point proceed very flowly towards the
Middle of the Drop, and fometimes much
beyond it, forming long Spikes moft ex-
quifitely fliarp-pointed, vid. e e.—A few
.extraordinary Figures appear fometimes,
ferrated on both Sides, but in a contrary
Direftion, and ending with a very ftiarp
Point, as is ftiewn at f. Others are like-
wife feen, now- and then, having four Sides,

with keen Edges that run tapering to a
Point, and form an Inftrument like the
long Head of a Spear exceedingly fliarp-
pointed, as at d.

When the Water is nearly exhaled,
another Sort of Configurations are formed
very fuddenly, confifting of innumerable
little Lines difpofed in a very curious and
■wonderful Manner, as the two Figures ƒƒ
endeavour to reprefent. And often (though
not always) one or two Configurations
Ihoot out, when one would think all over,
refembling what is ftiewn at g, but much
more elegant and regular, and refleóling
(I fuppofe from the extreme Thinnefs of
the component Salts) with great Brilliance
and Luftre all the beautiful Colours of the
Rainbow, if the Candle be placed to Ad-
vantage. Which Circumftance, together
with the Shape of this Configuration, in-
duces me to call it the Peacock's Tail.
The Configurations ƒƒ refledt Prifm Co-
Jours alfo, but in a much lefs Degree of
Perfedion

The Compartment B is intended to
fliew, what happens frequently to this and
many other Solutions, when a Drop is
placed on a Slip of Glafs, for Examina-
tion by the Microfcope: that is to fay,

fome fmall Part of the faid Drop becomes
fo feparated from the reft, as to make a
fort of fmaller Drop, wherein a more mi-
nute kind of Configurations are formed,
upon the fame Plan as the larger ones in
the Drop itfelf. And this the Reader may
conceive better, by viewing the Pifture be-
fore him, than by any Defcription in my

As Corrofive Sublimate and Arfenic are
two Poifons nearly alike in their Opera-
tion and fatal Confequences, I think it
beft to treat of them together in this
Chapter.

The Fumes that rife from ¹ Cobalt, in
making of Smalt from that Mineral, being
collefted under the Appearance of a whitilh
Soot, that Soot, by a farther Procefs, is
converted into the common White Arfenic,
which is what I now am fpeaking of.
It is brought to us in flattifti Pieces of
feveral Pounds Weight, and when newly
broken appears tranfparent like Glafs or

* Cehak is a hard and heavy mineral Subftance, common-
ly cf a blackilh grey Colour, fomewhat refemblirg the Ore
cf Antimony, but lefs fparkling and more difficult to break.
Some of it has Spots of a Purple or rather crlmfon Co-
lour, which are called the Floimrs of Cobalt. When
roafted or calcined in a revcrberatory Furnace with cer-
tain Proportions of Pot Afhes and common Salt, it pro-
duces a d6rk blue, glaffy, or cryftaline Matter called
Zaffer or Smslt, and the Fumes coUeaed in this Procefs
afford by different Management the White, TellofK, and

Cryftal, with a browniih Hue; but, after
a few Days, it becomes opake, acquires a
milky gloify Whitenefs, and looks like
white Enamel. When reduced to Powder it
appears extremely white, and is frequently
fold in the Shops by the Name of Ratjhane.

Notwithftanding this Subftance certainly
abounds, with Salts, as its cryftaline Ap-
pearance and its cauftic and corrofive Qua-
lities fufficiently evince, they are fo ftieathed
or locked up (as the Chemifts exprefs
themfelves) in their Sulphurs, that they
are very difficult to be feparated and brought
to View. Dr. Mead fays. White Arfenic
is entirely folubje, if one Part of it be
fufficiently boiled in fifteen Parts of di-
ftilled or Rain W^^ater which (with what
I ftiall mention prefently) gives me Reafon
to imagine there may be a Difference in
Arfenic, from perhaps a different Way of
preparing itj for notwithftanding I have
boi ed fmall Quantities, for a long while
together, in much larger Proportions of
Water, to the Confumption of the greatefi
J¹art, I always found moft of the Arfenic
at the Bottom undiffolved. Nor amongft
the Chemifts could I ever obtain any of
Its Salts, which I was greatly defirous to
•examine by the Microfcope f.

Mead on Poifons, 3d Edit. pag. 217.
t A Phyfician of great Eminence gave me once a fmall
;!eni.-tranrparent brown Mafs, ftiot out in Angles, which

Sometimes, indeed,- in a Drop of the
Water wherein Arfenic has been boiled, I
have difcovered a very few fmgle Oâaëdra,
confifting of eight triangular Planes, or two
Pyramids joined Bafe to Bafe ; which un-
doubtedly is the true Figure of its Cry-
ftals, as I have fmce been fully convinced
by the Affiftance of an ingenious Friend,
who found Means to diffolve an Ounce
of the nohite cryftalline Arfenic in about
three Pints of Water, of which, after eva-
porating a confiderable Part, he brought
a Phial-full to me. It was then a very
clear and ponderous Liquor, without any
Appearance of Cryftals: but in a few
Days, I found the Sides of the Phial,
even as high as the Surface of the Liquor,
pretty thickly covered with very mi-
nute Cryftals, adhering firmly to the
Glafs, fo as not eafily to be removed, but
diftindl and feparate from one another. On
examining them with Glaffes, I found them,
to be Oâaëdra, uncommonly hard and in-
foluble. After near fix Months I don't per-
ceive their Size to be at all enlarged, or their
Number to be increafed. A Drop of the

a Chemift had prefgnted to him as the true Salt of Arfenic,
and Ï had great Hopes by this to have gratified my Curi-
ofity : bur when I came to try it, I found it abfolutely i35-gt;
foluble even in boiling Water, after its being reduced to
Powder; and from its Appearance, its Hardnefs, and other
Circumftances, I am very fufpicious it was no other thai»
• conunon Spar,

Solution, examined on a Slip of Glafs,
either heated over a Candle, or left to
evaporate of itfelf, notwithftanding its be-
ing fated with the Particles of Arfenic,
produces no Configurations, and hardly any
Cryftals, leaving only a white Powder be-
hind it upon the Glafs : v/hofe Particles,
whilft the Water gradually evaporates, ap-
pear like minute Globules, even fmaller thaa
thofe of the Blood.

This V/hite ylrfenic is much more dan-
gerous than the yellow or red, being a
deadly Poifon to all living Creatures: the
Symptoms it brings on are much the fame
as thofe of Corrofive Sublimate, viz. Sick-
nefs. Fainting, Convulfions, cold Sweats
intolerable Heat and Thirft, Erofion of the
Stomachquot;-and Inteftines, Inflammation, Gan-
grene, and Death. But its Aftion is flow-
er than that of Sublimate, for its Salts are
lo iheathed by its Sulphurs, that they bemn
not to operate, till thofe Sulphurs become
rarified by the Heat of the Body, and fet
^fie Salts at Liberty; infomuch that a Pa-
tient may be faved after it has been fwal-
;owed half an Hour, by drinking large
^^antities of Olive-Oil, or melted fre^

oy Uifcharges upwards and downwards, an
Abatement of the Symptoms fhews the Poi-

mended in this dangerous Cafe, along with
the foregoing Remedies, as a Corredor of
this Poifon, and fo likewife is Milk. The
fame Method is advifeable where Sublimate
has been fwallowed, but then it muft be em-
ployed very fpeedily, or no Relief canbeex-
pedled. After either of thefe Poifons has
been difcharged, drinking Milk for a few
Days, and a gentle Purge or two, are very
proper to complete the Curenbsp;^^

• Dr, Blair, In hh Letter to Dr. Mead, on the Effefls
of Arfcnic upon human Bodies, gives two remarkable
Cafes • the one of a Woman, who was killed by this Poi-
fon mixed with Flummery ; which (he eating about eleven
0'Clock at Night, was feized immediately with violent

in the Morning, when fhe died convulfive. The Poifon
iiad been fo well wrapt up in the Flummery, that on
her being opened the Oefopbagus was no ways altered .
lut thé Doftor was furpri7;ed to find the Stomach fo fu I
cf Liquor having been informed fhe had eat or drank
very bttle the Day before the Poifon yeas given. It
contained a greeniamp; Subftance, without any Colour or
Appearance of fuch a digefted Mafs as ufes to be m
Ihe Stomach, with feveral thick Coagula about the Big-
nefs of Walnuts, fufpending fome fmall Quantities of »
profs Powder. When this Liquor was emptied,
W found redtlife and blackilh ftris all over the Piloru9,
fo many infiamed Lines refembling the Branchings
of Blood-yeifels, upon which the grois, whiffti, hari
Powder lay in fuch Quantity that after bein^ell dried
it weii-bed between a Scruple and half a Igt;ram. AH
.i!ong the Inteftines, as he laid them open down to the
Anul, he found fo much of the fame Kind of Liquor,
Without either Colour, Confiflence, or Smell of an Ex-
crement, as filled a Quart Bottle: which feemed extra-
ordinary, confidering the great Evacuations before hei

The Fumes or Steams of Arfenic are ex-
ceedingly pernicious, and commonly diftin-
guifli themfelves by an abominable linking
Smell like Garlic; tho' OttoTachenius {^js',
in his Hippocrates Chemicus, that after many
Sublimations of Arfenic, on opening the
Veffel, he fucked in fo grateful and fweet a
Vapour that he greatly admired it, having
never experienced the like before: but in
about half an Hour, his Stomach began to
ake and became contracted, a Convulüon of
all his Limbs fucceeded, he made bloody
Urine with incredible Heat, was feized with

Primae Vilt;e muft have been moft violently compreffed, to
fqueeze fuch Quantities of Liquor into the Stomach and
Inteftines.

The other Cafe is of a Lady, who on tafting (by
Miftake) only fo fmall a Qnantity of White Arfenic as
adhered to the Tip of her finger, found herfelf with-
in two Hours in great Diforder, grew faint, fell in a
Swoon, and loft her Senfes before (he could be laid in
Bed. A Phyfician being called, prefcribed an Emetic,
which made her vomit a large Quantity of 'quot;uch Sort of
greenifti Liquor as in the former Cafe ; after which Ihe
voided by Stool feveral Globules of greenilh Coagulum,
of the Bignefs, Colour, and nearly the Confiftence of
pickled Olives. Thefe Difcharges being over, and Alexi-
pharmics given, Ihe ftveated plentifully, and flept well,
and when (he awaked her Skin was fpeckled with livid
and purplilh Spots. She recovered in a few Days, and
became perfeftly well. The Doftor obferves, that thefe
greenilh Coagula are what Arfenic ufually produces, when
'nternally given; the Knowledge of which may be of
Ufe to thofe who may have Occafion to open Bodies on
Sufpicion of their having been poifoned thereby. Sec
mairt Miß. Qhßr'uations, pag. 62.

Cholic Pains, and cramped all over for an
Hour or tw^o; when thefe ugly Symptoms
svere taken away by his drinking Milk and
Oil, and he became indifferently well; they
quot;were followed however by a flow Fever like
an Hedtic, which fl:uck by him the whole
Winter, and of which he recovered very
flowly by a proper Regimen in Diet

The extreme Subtilty and Penetrability of
thefe Steams are remarkably manifefl: by
their furprizing Effedt in the Experiment

• Glauber tells us, in his Treatife de Salihus, that C«-
lalt and Arfenic, though violent Poifons, are yet harmlefs
unlefs taken in Subftance, but if exalted by a Sublimatioa
with Saks and rendered volatile, the very Fumes of them
will kill, as is well known to thofe who prepare the
Water called Jqua gradatoria from a Mixture of Vitriol,
Nitre, and Arfenic, the leaft Vapour or Fume whereof
xnftantly afFi.as the Heart with the moft horrid Tremors,
and exceedingly diforders the Brain itfelf: a Candle
will likewife be nearly extinguilhed in the faline Fumes
thereof.

In Dr. Mead's Mechanical Account of Poifons, 3d Edit,
pag. 225, are thefe Words, quot; I had once in my Pof-
'' feffion, given me by an ingenious Chemift, a clear Li-
quot; quor, which though ponderous, was fo volatile, that it
quot; would all ily away in the open Air without being
quot; heated ; and fo corrofive, that a Glafs Stopple of the
quot; Bottle which contained it, was in a ihort Time fo
quot; eroded, that it could never bs taken out. The Fume
quot; from it was fo thin, that if a Candle waj fet at fome
quot; Diftance from the Bottle, upon a Table, the Heat would
quot; direft its Courfe that Way; fo that it might be poifonous
quot; to any one that fat near to the Light, and to nobody
quot; befides.quot; The Doftor very humanely conceals this
Conipofition, kit an ill Ufe might be made thereof.

* As fome of jny Readers may pofiibly not know the Ex-
periment here referred to, I ihall give it by Way of.
Note, which thofe acquainted with it may if they pleafe
pafs over.

Orpiment half an Ounce, and one Ounce of Quicklime,
being powdered feparately, then mixed together, and put
into a Matrrfj with five or fix Ounces of Water, ftop the
Veffel clcfe, and digett in a gentle Sand Heat for ten or
twelve Hours, lhaking the Mixture ofteji. The Liquor,
when fettled, will be very clear.

This being prepared, write, with a ftrong Solution of
S.accharutn Batumi made in common Water, on a Piece of
clean Paper, and when it is dry nothing will be feen at
all. Put the Paper with this invifible quot;Writing betweea
the very beginning Leaves of a Book; then v»ith a Brufh
or Piece of Spunge, dipt in the Liquor prepared with Or-
piment, wet another Paper, and place it at the End of
the fame Book, oppofite to the firft Paper. Shut the Book
nimbly, and with your Hand ftrike on it two or three
fmart Blows; and if it be very thick fqueeze it in a Prefs,
or fit upon it a few Minutes: after which, on opening
the Book, you'll find the invifible Writing black and legible,
by the fubtile Penetration of the Steams of the Orpiment
through all the Leaves.

Quench burning Cork In Spirit ofWine, and when 'tis
finely powdered make Ink, by mixing a fufficient Quan-
tity of it in Water a little thickened with Gum. Write oa
ƒ Paper with the Solution of Saccbarum Ssturni, and when
tis dry and invifible, write again upon the fame Placc
with your Cork and M'ater, which will appear like com-
mon Ink; when 'tis dry rub it over with fome Cottoa
^vetted in the Preparation of Orpiment, and immediately
the Writing that was vifible will difappear, and the in-
vifible Writing will prefent itfelf very legible inftead there-
of' Thefe are pretty Experiments, which I feveral times
have tried ; but they Ihould be made in the open Air,
and with great Caution, the Fumes of the Orpiment ftink-
ing moft abominably, and being prodadive of great Mifp
fhiefs if taken into the Lungs.

3er into a beautiful Refemblance of Silver^,
but renders it brittle at the fame Time.

A R s E N T C being the Poifon moft commonly made Ufe
of by wicked People to deftroy others, and by defpairing
Wretches to put an End to their own Lives, I (hall 1 hope
fceexcufed, for adding this Note of Inftruaion how to make
Trjai of any Subftance fufpefted of being Arfenic: and like-
wife how to judge of the Symptom? it produces when taken ;
colleaed from the recent unhappy Cafe oïUt. Blandy.

This Gentleman was poifoned by Arfenic, given him by
his own DaLgluer in Water Gruel; at the Bottom of a
Pan of which a Servant Maid finding an onufual white
gritty Subftance, and fufpeaing Mifchief, from having feen
her Miftrefs ftirnng fomething into it, ftie Ihewed it to an
Apothecary, who faved a little Quantity of the Sediment,
which was dried, and examined by Dr. Addington.

The Doaor's Account of White Arfenic upon the Trial
of Mifs Blandy, was, that when powdered it has a milky
Whitenefs, is gritty and almoft infipid. Part fwims on the
Surface of cold Water like a pale falphureous Film, but
the greateft Part finks to the Bottom, and remains there
undiffalved. Thrown on red-hot Iron, it does not flame,
but rifes intirely in thick white Fumes, which have the
Stench of Garlic, and cover cold Iron held over them with
white Flowers. The Powderhe examined did exaaiy the fame.

He boiled ten Grains of powdered Arfenic in four Ounces
of clean Water, which he filtered, divided into five equal
^arts, and put into as many Glaffes.—On pouring into the
firft Glafs a few Drops of Spirit of Sal Ammoniac, it threw
dov^ a few Particles of a rale Sediment. Some Lixivium
of Tartar poured into the fécond, produced a white Cloud
hanging a little above the Middle of the Glafs. Strong
Spirit of Vitriol poured into the third, made a confidert
able Precipitation of a lightilh coloured Subftance, which
hardened into glittering Cryftals, fticking to the Sides and
Bottom of the Glafs. Spirit of Salt poured into the fourth,
precipitated a lightifh coloured Subftance. Syrup of Violets
in the fifth, produced a beautiful pale greén Colour.—
Ten Grains of the Sediment from the Gruel, tried in the
lame Manner, afforded the fame Appearances exaaiy.

i he Symptoms produced by this Poifon in Mr. Blandy,
were burning and pricking in the Tongue, Throat, Stomach,
and Bowels, Sicknefs, Gripings, Vomiting and Purging,

bloody Stools, Excoriation of the Fundament, Swelling of
the Belly, exquifite Pains and Prickings in every external as
well as internal Part of the Body, which he compared to aa
infinite Number of Needles darting into him all at once.
Uneafinefs in the Mouth, Lips, Nofe, and Eyes; Lips dry
and rough with angry Pimples on them, infide of theNoftril»
in the fame Condition, the Eyes a little Bloodihot; cold
Sweats, Hiccup, extreme Reftleffnefs and Anxiety, low,
trembling, intermitting Pulfe, difficult unequal Refpiration,
Difficulty of Speech, Inability of Swallowing, and (the Goti-
fequence of all thefe cruel Symptoms) Death.

Dr. Addington and Dr. Lemiis, on examining the dead Body,
found it in the following Condition, 'viz. The Back, hinder
Part of the Arms, Legs, and Thighs, were livid. The Fat oa
the Mufclesofthe Belly of a loofe Texture, inclining to a
State of Fluidity; the Mufcles themfelves pale and flaccid.
The Cawl yellower than natural, and on the Side next the
Stomach and Inteftines, brownifli. The Heart variegated
with purple Spots; and no Water in the Pericardium. The
Lungs like Bladders filled with Air, and blotted as it were
in fome Places with pale, but in moft with black Ink.
The Liver and Spleen much difcoloured : the Liver look-
ed as if boiled, but that Part which covered the Stom^h.
particularly black. The Bile fluid, of a dirty yellow in-
clining to red. The Kidneys ftained all over with livid
Spots. The Stomach and Bowels inflated, and appearing,
before any Incifion, as if pinched and extravafated Blood
had been ftagnated between their Membranes. They
contained nothing, as far as they were examined, but a flimy
bloody Froth : their Coats remarkably fmooth, thin, and
flabby. The Wrinkles of the Stomach totally obliterated
its internal Coat and the Duodenum prodigioufly inflamed
and excoriated.—-Vid. Mijs Blandy% Trial, Folio, pages

^^'h^Arjtnic L not ufed in Medicine, it would be well if the
Apothecaries and Cheaiifts did not keep it in their Shops.
Selling now and then a Pennyworth to kill Rats (and even
in doing that many fad Accidents have happened) can furely
induce no good Man to rifle the Foflibiluy of puttmg thw
^orrid Poifon into wicked Hands.

1 ^ H E pretty Shootings of this extra-
J[ ordinary Salt are exceedingly enter-
taining, though its Progreffions are fo very
flow, that fome Patience is neceifary to wait
for and attend to the whole Courfe of its
Configurations : but a curious Obferver will
find from it at laft a Pleafure fuflicient to
reward his Attention.—Its firft Shootings at
the Edge of the Drop, after it has been held
for a few Seconds over the Flame of a Lamp
or Candle, appear irregular, as at a a, Plate
v. Somx F igures pufti out foon after, be-
yond the reft, and are curved and tapering
to a Point, as b b. Very elegant Figures will
quot;be feen forming themfelves in other Places
at the fame Time, and refembling Sprigs
of Fir or Yew : Numbers of thefe rife to-
gether, each having a main Stem very
thickly befet with little Shootings from Top
to Bottom, in fome on both Sides, but in
others on one Side only ; which Difi^erence
will be underftood by a View of the Figures
€•€. The downy Feathers of Birds appear
in the fame Kind of Form when examined
by the Microfcope. As the Progreftion goes
on. Branches will be found ifttiing from the
Sides of the former Shootings, vid. d : and
in fome Places of die Drop feveral Grada-
tions

tions of Branchings v/ill be perceived to fuc-
ceed one another, to divide and fubdivide af-
ter a moft vi^onderful Order, reprefenting at
the laft a Winter Scene of Trees v^ithout
Leaves, a Specimen of vt^hich is £hewn at
—The laft Aftion of this curious Salt pro-r
duces Figures exquiiitely delicate, bearing
no Rcfemblanee to any Thing that preceded,
but appearing like the Flourilhe-s or Engrav-
ings of a mafterly Hand, in the Manner re-
prefented at ƒƒ. This Part of the Opera-
tion begins not till the Water is nearly ex-
haled, and whilft it is performing the Scene
appears a good deal confufed; but after
waiting till the Water is intirely dried away,
a thoufand Beauties will prefent themfelves
perfectly diftrnd: and clear; for the Confi-
gurations of this Salt do not break away,
or melt in the Air, as moft others do, but
may be preferved on the Glafs Slip for a long
While afterwards, if fo be nothing is fuffered
to rub them off.

^ It would give me great Pleafure, was
It poffible, from the Configurations of
this Salt, to trace out, with any Degree
of Certainty, the Generation or Pro-
dudion of Amber; a Subjedt about which
Naturalijis are exceedingly divided and
perplexed: Some fuppofing it an animal
Subftance, others a refinous vegetable con-
creted Juice, and others a natural Foflil or
Mmeral: but the Shootings of its Salt are
io very difterent from every other Kind, that
ionbsp;they

they afford little or no Ground on which to
raife a Conjedure : however, the general
Figures round the Edge have I think a Sort
of mineral Charader, and the Feather-like
Bodies tend a little towards the Shootings of
fome of the Vitriols. The curved fmgle Lines
ƒ/; which appear like Drawings with a Pen,
are fo peculiar to this Salt, that, for Want of
finding them elfewhere, one can form no
Judgment from whence they derive their
Form; and the Cafe is the fame as to thofe
Shootings which refemble naked Trees. I
fhall not pretend therefore to infer any Thing
from thefe Figures : but, before I intirely
quit the Subjeft, (hall prefent a few ^eries
to the Confideration of my curious Readers.

^ere i. Does not Amber, when analy-
zed, afford a confiderable (Quantity of 0/7, in
Smell, Colour, Inflammability, and Confifl:-
ence like the White, or rather Amber-co-
loured Naptha, a Proportion of Acid Salt,
and a Caput Mortuum or earthy Subftance ?
and if fo, does it not feem probable, that
fuch a bituminous Oil fixt by an acid Salt,
with more or lefs of an earthy Subftaqccj, is
really the Compofition of Amber * ?

* In the Diftillation of Amber there firft rifes a thin lim-
pid Oil, then an Oil yellow and tranfparent, which is fuc-
ceeded by a volatile acid Salt and a red Oil fomewhat clou-
dy : a grofs fat Oil like Turpentine comes over next, and
laft of all a thick black Matter. At the Bottom remains a
fmall Quantity of a Caput Mortuum. Vid. Bcerhaanie'i Ana-
Jyfis of Amber, Vol. Ild of his Chemiftry, Procefs 87. Hart-
«aa obtained an Ounce of volatile Salt from lib. of white
Amber, whereas j lb. of yellcrw afforded fcarce a Dram.

Sgt;uere 2. If it be inquired, where thefe
Materials are to be found, and how they can
be brought together ? may it not be anfwer-
ed, that in fome Countries, and particularly
in Perfia, near the Cafpian Sea, there are
Springs where Naptha rifes out of the
Bowels of the Earth; and that the Ground
thereabouts is fo faturated therewith, that, on
fcraping off the Surface, and applying a
Candle near it, a Fume arifing therefrom im-
mediately takes Fire, and continues burn-
ing, with a clear and conftant Flame, until
it becomes extinguifhed by throwing Earth
upon it, or fmothering it by fome other
Means ¹ ? If therefore, fuch bituminous

1nbsp; Two Letters now lie before me, with Accounts of thefe
Naptha Spring»; one from Dr. James Mounfej, Phyfician to
thé Army of the Czarina, the other from Jonas Hanivay, Efq;
both Gentlemen, who by their Travels, their Refidence in
Mu/co'vy, and their Acquaintance with feveral People who
have been upon the Spot, have had great Opportunities of
becoming perfeftly informed of every Thing relating to this
Subjeft ; and whofe Judgment and Veracity may be depend-
ed on. Both their Accounts agree, that on the Weftern
Coaft of the Cafpian Sea, not far from the City of Baku, there
is a large Spot of Ground, where, on taking off z or 3 Inches
of the Surface of the Earth, and then applying a live Coal,
the Place uncovered catches Fire, even before the Coal
touches the Ground, and fends forth a light blue Flame,
which goes not out unlefs it be fmothered by throwing Earth,
or fomething elfe, upon it. This Flame makes the Earth
hot, but does not confume it. If a Tube (even of Paper) or a
Reed be fet about two Inches in the Ground, and made clofe
below with Earth, on touching the Top of it with a live
Coal, and blowing, a Flame immediately ilTues forth, with-
out burning either the Reed or Paper, provided the Edges be

Oil be found, and in fufficient Qiiantity, our
next Enquiry will be concerning the Acid
Salt: as to which, are not the Chemifts pret-
ty generally agreed, in fuppofmg, that what
they call a Vague Acid (whereby they mean,

covered with Clay. This Method fupplies the watit of Can-
dles in their Houfes. Three or four of thefe Canes will alfo
boil Water in a Pot, and they drefs their Viftuals with it.
The Flame may be blowed out like that of a Lamp, but
othenvife it continues burning; it fmells fomewhat fulphure-
ous, or rather like Naptha, but very little ofFenfive. The
Ground is dry and llony, and the more ftony the Ground
the ftronger and clearer the Flame. Near this Place they
dig Briniltone, and here are alfo Naptha Springs. But the
chief Place for Naptha is Siuieten llland, a fmall 1 Vaft of
Land on the Weftern Coaft of the Cafpian Sea, and uninhabit-
ed, except at fuch Seafons as they fetch Naptha from thence :
which the Perjians load in their wretched Embarkations with-
out Barrels or any other VefTels, fo that fometimes you fee
the Sea covered with it for Leagues together. The Springs
boil up higheft in thick and heavy Weather, and the Napth^
fometimes takes Fire on the Surface, and runs lighted or
burning into the Sea in great Quantities, and to great Dif-
tances. In clear Weather it does not bubble up above two or
three Feet. People make Cifterns near the Springs, into which
they convey what overflows by Troughs, taking off the Nap-
tha from the Surface, under which there is a Mixture of
Water or fome heavier Fluid. The greateft Part is of a
dark grey Colour, very unpleafant to the Smell, but ufed in
Lamps by the poorer Sort. There arc alfo Springs of black
Naptha, which is thick, and on DilUlIation grows not clear
but yellow ; but the moft valuable is the white Naptha, which
is naturally clear and yellovvifh, and bears a great Price.
The Ruffians drink it as a Cordial, but it does not intoxi-
cate : ic is ufed alfo for tains or Aches, and is carried into
India as a great Rarity, where they make with it the moft
beautiful and lafting Japan that has ever yet been known.

What the Indians call the Ewrlajiing Fire, lies about ten
Englifh Miles, N. E. by E. from the City of Baku, on dry
xocky Ground. There are feveral ancient Temples, built with
Stone, fuppofed to have been all dedicated to Fiiej moft of them

if I underftand them aright, a volatile fub-
tile Vapour, Fume, or Spirit) exifts in the
Bov^els of' the Earth, and throughout the
Atmofphere near the Surface thereof; and
that by pervading, intermixing, or concret-
ing with different Subfiances, it compofe»

are low arched Vaults, from lo to i j Feet high. Aroangil
■the reft there is a Temple in which the Indians now worfhip ;
near the Altar, about three Feet high, there is a large hol-
low Cane, from the End of which iifues a Flame, in Colour
and Gentlenefs not unlike a Lamp that burns with Spirits.
The Indians affirm, this F}ame has continued burning fome
thoufands of Years, and believe it will laft to the End of the
World, and that if it was refifted or fappreffed in this Place,
it would rife in fome other. By the Number of Temples it
is probable here were formerly a great Number of Worfhip-
■pers of Fire, as well JndiAns as Per/tans : they are calledl
£euers. At prefent here are only aboUt twenty Eerfons, who
refide conftantly and go almoft naked. In Summer it is
very hot, and in Winter they dwell within Doors, and can
keep what Fire they pleafe in the Manner above defcribed :
they live upon Roots and Herbs for the moft Part, and are
fuppofed to attend as Mediators for the Sins of many who are
abfent: and by their Application to this Fire, in which the
Deity is fuppofed to be prefent and vifible, they atone for
the Sins of others. A little Way from the Temple juft now
mentioned, near Baku, is a low Cliff of a Rock, in which
there is an horizontal Gap 2 Feet from the Ground, between
5 and 6 long, and about 3 Feet broad, out of which iffues
a conftant Flame, much of the Colour mentioned already,
being a light blue. It rifes fometimes 8 Feet high, but is
»»ore low in ftill Weather. They don't perceive the Rock
*vaftes in the leaft. This alfo the Indians worlhip, and fay it
cannot be put out. About 20 Yards on the Back of this Cliff
Js a Well, in a Rock 12 or 14 Fathoms deep, with exceed-
ing good Water.

, The curious Particulars contained in this Digreffion will,
tis hoped, excufe its being inferted.

I received with thefe Letters fome of the white Naprha,
Which in Colour, Smell, and Tafie, refembles mach the fineft
♦.in^ of Oil of Amber,

Vitriol, Alum, Nitre, and feveral metallic and
.'mineral godies ? May it Aot then be ima-
gined poffible for thi$ fame acid Vapour fo
to mix with and confolidate fuch bitumi-
nous foffil Oil, or Naptha, as thereby to
produce Amber ?

^ere Is there any thing In the Ap-
pearance of Amber, or in the Places where
it is found, that may conduce towards
forming fome probable Conjedure concern-
ing the Produdlion of this Body* ?

^ere 4. Do not the feveral Species of
In feds found in Amber, prove, beyond all
Difpute, that it mufl have been in a fluid
State at the Time thofe Infedls were in-
tangled in it ? Are not the Springs or Ooz-

• We are told, that where Amber is met with in Quan-
tky, there is likewife conftantly an Abundance of Vitriol.
No Country yet known affords more or better Amber than
Fruffia, where it lies, as Hartman fays, in a Kind of ^tra-
tum or Bed, intermixt with a Subftance refembling foffil
Wood or Bavk, but whofe Origination he imputes to a
fat Ipituminous Earth : Vitriol a^nd Bitumen are alfo here
in Plenty, and he was informed there are Springs of Oil
rifing out of the Ground; from all which Circumftances
put together, his Conclufion is, that the Exhalations of Bitu-
nien (from a fubterraneous Heat) are collefied into Drops ;
that the fame Heat pervading the neighbouring Salts, car-
ries their Effluvia along with it, and mixes them with the
bituminous Drops; whence he fuppofes, that the faline
Spicule fix the Bitumen and produce Amber, which is
more tranfparent, better fcented, and firmer, according to
the Purity and Proportion of the bituminous and faline Ex-
'halations. Vid. Phil. Tranf. Nquot; 248. May not fome of
the foffil Oil here mentioned be as eafily fuppofed to have
Lfien fixt by t,he faline Effluvia or Spiculs ?

ings of Naptha out of the Earth in Places
where Infeits might be likely to fall into
it ? Suppofmg which, might it not perhaps
have been hardened or congealed by the
acid Vapour foon after their being fo in-
tangled ? though that is not abfolutely ne-
celfary, fince Naptha will preferve Animal
Bodies a great Length of Time. Is it not
found on Trial, that the Wings, Horns,
Legs, of very fmall Creatures fpread and
extend themfelves much better in Naptha,
or fine Oil, than in Water or any watery
Fluid ? and may not this account, in fome
Meafure, for the Perfedtion in which fome
very fmall Infects appear, when embodied
in this Subftance ?

^ere 5. As the Earth affords bitumi-
nous Fluids different in Colour, Confiftence,
and Purity, may not white Naptha (fo call-
ed, tho' of a pale yellow) which is the moft
pure of all, be fuppofed capable of being
concreted into the beft and cleareft Amber ?
rnay not a coarfer and browner Naptha
compofe Amber more indifferent ? and may
not a black Kind be converted by the fame
Chemiftry of Nature into Jet and Afphal-
tum ?

^ere 6. Is it wholly improbable that
fome bituminous Juice, or foflil Pitch, mix-
ed and concreted with Earth, or perhaps
fome other Matter, may be the Compo-
fition of Coal ? and fliould it be inquired
Vol. ILnbsp;Lnbsp;where

where an acid Spirit can be found for the
fixing and confolidating thefe Principles ? do
not the Choak Damps in rnofl Coal Pits prove
the Exiflence of fuch a Spirit within the
Bowels of the Earth ? do not thé Fire
Damps, frequent in the fame Pits, likewife
prove the Abundance of a bituminous Va-
pour inflammable like Naptha ?

^lere. 7. Do not the Brittlenefs and
Lightnefs of Coal, Jet, and Amber, fome-
what countenance the Opinion of their be-
ing of an oily and bituminous Compofition ?
and if fo, what Fluids does the Earth afford
fo likely to conftitute thefe Subftances as *
Fq/pl Pitch, Petroleum, Oleum F'errce,^n^ the
different Sorts of Naptha ?

* Captain John Poyniz, in his Account of the Ifland of
7'ciago, p. 58, fays, quot; Green Tar iffues out of the Earth from
quot; th'è Mufijaci Rods, and is commonly gathered after a
Shower of Rain, by fcimming it ofr from the Surface of
quot; Water: then potting it into a great Gourd, or fuch
like Veffel, that has an Hole at the Bottom, they feparate
quot; the Oil from the Water, by fuffering the Water to Aide
quot; gently out, but when the Oil appears, they cautioufiy ftop
quot; and preferve it for feveral Ufes, as to burn in Lamps, i^c.
quot; The Munjack is nothing ell'e than a Confirmation or Coa-
«« gulation of the Tar (we fpoke of) into a more folid
quot; Body; which Muvjack were it in a frigid, as it is in
the torrid Zone, would be abfolute Coal, fuch as we
quot; burn in England''

WH A T I am now about to treat
of under the Name of Scarborough
Salt, was bought at one of the principal
Water Warehoufes in London, at a good
Price; and was affirmed by the Seller to be
a true and genuine Salt prepared from the
Scarborough Well.

Some of this being diffolved in Water, a
Drop of the Solution begins fhooting from
the Edges : firfl of all, in Portions of quadri-
lateral Figures, much like thofe of common
Salt j but their Angles inftead of 90 are of
about 100 Degrees. Thefe Figures fhoot
in great Numbers round the Borders of the
Drop, having their Sides as nearly parallel
to one another as the Figure of the Drop
will allow : fome proceed but a little Way,
others farther, before they renew the Shoot,
vid. a a, Plate V. In fome Places they
appear more pointed and longer, as at b, and
fometimes inflead of the diagonal, one of
the Sides is feen towards the Edge, and the
other fhooting into the Middle, as e.

The inward Configurations feem to owe
their Forms moflly to Vitriol, and are all
produced by the fame Method of Shooting :
though fome proceed from the Figures ai-
L 2nbsp;ready

wards into very pellucid and beautiful Ra-
mifications, as d d. Some Figures owing
their Form to common Salt, like that fhewn
at e, are ufually the Fore-runners of another
Kind of Configuration arifing from the
fame Principle, which fhoots pretty fud-
denly, and appears not much unlike the
Covert Way and the Glacis or outward
Slope of a fortified Place, vid. f f.

This Salt was bought at the fame Place
as the foregoing, and with the fame Affu-
rance of its being genuine. When kept a
little while it crumbled into a white Calx or
Powder, though it was at firft in very fair
Cryfials.

Drop of the Solution of this Salt be-
^ ^ gins to fhoot from the Edge in jagged
Figures like thofe fliewn at a, Plate V. From
other Farts of the Edge different Configura-
tions extend themfelves towards the Middle,
fome whereof have f^ne Lines proceeding
from both Sides of a main Stem, in an oblique
Diredlion, thofe on one Side fhooting upwards
in an Angle of about 60 Degrees, and thofe
on the other downwards in the fame Obli-
quity, as at c and ƒ. Others produce Jaggs

from their Sides nearly perpendicular to the
main Stem, thereby forming Figures that
refemble the Branches of fome Species of
Polipody: thefe are reprefented at e: but in
others the Jaggs are fhorter, vid. d. Now
and then one of the main Stems continues
fhooting to a confiderable Length, without
any Branchings from the Sides, but at laft
fends out two Branches from its Extremity,
as at g. Sometimes a Figure is produced
having many fine and minute Lines radiat-
ing from a Center, in the Manner fliewn at
b. The laft Shootings in the Middle of the
Drop may be feen at h, and are not unlike
the Frame Work for the flooring or roofing
of an Houfe, but with the Angles a little ob-
lique : and fometimes a Form prefents itfelf
like that fliewn at /.

All thefe Figures muft be produced with
a very fmall Degree of Heat, for if the Drop
be made too hot the Salt will not flioot at
all: but when once the Configurations are
formed, the Salts fix, become fmooth and
hard like Glafs, and may be preferved a long
Time.

The Subjedl above defcribed was not the
true Salt of the Epfom Waters, which I knew
not where to get; but it was I believe fome
fort of Preparation like what is commonly
fold under the Name of Epfom Salt, at a
?ery cheap Rate: though I gave a much

ABon Salt, or what I bought for fuch,
appeared on Examination juft like the above,
but without the Figures h i g.

in the Figures fhewn at b: but if only a
fmall Degree of Heat be employed, it forms
many very tranfparent Parallelograms, fome
having one, and fome more of their Angles
fecanted, as at c.

This Salt is a Mixture of Nitre and Sul-
phur in equal Quantities, fet on fire in a
Crucible by a Spoonful at a Time, after-
wards diffolved in warm Water, filtered and
evaporated. It purges by Stool and Urine.

After the Diflillation of Spirit of
Salt with Oil of Vitriol, (from Oil of
Vitriol, common Salt and Spring Water in
equal Quantities;) what Salt remains at the
Bottom of the Retort, being diflblved, fil-
tered, evaporated, and cryftalized, is called
Glauber's wonderful Salt.

A Drop of Water faturated with this Salt,
and gently heated over a Candle, produces
Ramifications from the Side of the Drop,
like the Growth of minute Plants, but ex-
tremely tranfparent and elegant, in the Man-
ner fhewn at c, Plate V. Some of them
however begin to ihootfrom a Center at fome
Diftance from the Edge, protrude Branches

from that Center in a contrary Diredtion, and
appear fomewhat like a Bundle of Grafs or
Twigs tied together in the Middle, as at b :
they likewife fhoot fometimes from one and
fometimes from more Sides of the central
Point, in the Varieties fhewn at //.

Other Figures are produced from diffe-
rent Parts of the Edge of the Drop, as at «
and ƒ, as alfo the parallel Shootings at e:
but the moft remarkable and beautiful Con-
figuration forms itfelf lafl of all near the
Middle of the Drop : it is compofed of a
Number of Lines, proceeding from one
another at right Angles, with tranfparent
Spaces and Divifions running betweep them,
appearing altogether like Streets, Alleys,
and Squares, as reprefented at g This
Figure plainly owes its Original to Marine
Salt, and is of the fame Kind with that
fliewn at ƒƒ, in the Cheltenham Salt. The
Figures a and e are vitriolic.

When this Configuration begins, it forms
with wonderful Rapidity, affording the Ob-
ferver a very agreeable Entertainment : but
he mufl: watch it carefully, for as it is'pro-
duced almoft iriftantaneoufly, jts Beauty is
of a very fliort Duration : in a few Moments
It difTolves and breaks away like melted Ice,
which renders the Drawing of it very difJi-
cuk. The Figure in the Plate was taken
at feveral Times and with different Drops,

If the Solution be not heated in the Bot-
tle, to diffolve the Sediment it throws down,
little will appear but the Brufh-like Figures.

Glaubers Salt is reckoned to anfwer the
Intention of moft purging Waters : it pro-
motes Evacuation both by Stool and Urine,
and may be fo made as to be lefs naufeous
than mofl other artificial purging Salts.

A FTER heating a Drop of the Solu-
tion of this Salt, there arife in many
Places, near its Edges, Numbers of minute
Bodies, pretty irregular in their Form, but
inoftly inclining to be triangular j as may be
feen in the Drawing, at the Side b. (fee Plate
VI.) Several of thefe appear likewife farthet
within the Drop,' and produce all the Varie-
ty of Figures cc, dd,^c.—There flioot at the
fame Time, from fome Parts of the Edge,
tranfparent Bodies with parallel Sides termi-
nating as at a, fome whereof are flrewed
over with the little Triangles before defcrib-
ed. From other Parts of the Edges branch-
ed Figures prefent themfelves, refembling
fmall Shrubs, fvid. f.) whofe Twigs are

naked at their firft Shooting, but appear
foon after covered with little Leaves or
Tufts; the minute Bodies above mentioned
which rife near the Twigs being attraded by
and adhering to them.

But the moft odd and ftngular Circum-
ftance in the Shooting of this Salt is, that
ftrait Lines appear, two and two, inclining
toward each other from the Edge of the
Drop where they begin to flioot, but never
meeting fo as to form a Point, though fome-
times they extend almoft acrofs the'Drop,
vid. e.'— They may poffibly. be cylindric
Tubes, but of that I am not certain.

Crude Tartar, calcined, diffolved in warm
Water, purified by Filtration, and evaporated
to a Drynefs, becomes what is ufually called
Salt of Tartar: which Salt tied up in a Cloth,
and hanged in a damp Place, attradls the
Moifture of the Air, and liquifies in fuch
Manner, that from one Pound thereof there
will drop down double its Weight of what
is termed Oil of Tartar per deliquium: but
inftead of this the Shops frequently fell ¹
Pearl Afhes liquified by the Air, which they
reckon equally ufeful for the fame Purpofes.

Some likewife imagine there is no Dif-
ference in the medicinal Virtues of the Salt

of Tartar and thofe of Pearl Afhes, or any
other of the lixivial Salts of Plants, all which
they fuppofe to receive alike the fame Qua-
lities from the Fire : but the contrary to this
will I believe be manifeft, from an Exami-
nation of the Salts I am going to fubmit to
the Reader's Judgment; the Configurations
and Cryftals whereof are fo widely diflimi-
lar, that one can hardly conceive them to
arife from exaftly the fame Principles in the
Salts themfelves, or to produce exadly the
fame Effeds when applied to other Bodies.
'Tis indeed probable that the effential Salts
of Plants, colledted in the Form of Cryftals,
from the Juices of their refpedlive Plants,
without the Help of Fire, may be different
from the Salts of the fame Plants procured
by Incineration, and may have different Vir-
tues : but I think fuch effential Salts can
hardly differ more from one another, when
examined by the Microfcope, than the lixi-
vious Salts of different Plants are found to
do; and confequently that thefe lixivious
Salts muft have Virtues very different from
one another.

The making effential Salts being a trouble-
fome as well as tedious Operation, dnd con-
fidered only as a Matter of Curiofity, none
of the Shops could afford me any of them;
and even of the lixivious Salts, the Opinion
of their being all alike has fo much reduced
their Number, that had it not been for the

great Civility of Mrs, Glutton and Mr. Cor bin,
Chemifts and Partners, in Holborn, (whofe
kind Affiftance I thankfully acknowledge
in this public Manner,) it would have been
in my Power to procure Very few of thofe I
ftiall hereafter mention.

rT-^HE reaified Oil, or reaified Spirit of
Vitriol, dropt gradually into Oil of
Tartar per deliquium, till it caufes an Ebulli-
tion, produces (by evaporating the Hu-
midity) a white Subftance called vitriolated
Tartar *.

This diflblves readily in hot Water, and
a Drop of the Solution applied on a Slip of
Glafs before the Microfcope, begins ftioot-
ing round the Edge in great Numbers of
very minute and tranfparent Spicules, de-
tached intirely from one another, and with-
out any of that Bafis at the Edge of thd

• Vitriolated Tartar is commonly an Ingredient in Pow-
ders for the Teeth, as on rubbing them with it they be-
come white immediately : but it Ihould be ufed feldom and
with great Caution, wafting the Teeth well with feveral
Mouthfuls of Water afterwards: for it whitens them by
Erojion, and if frequently applied will deftroy their out-
ward clofe and hard Coat of Enamel, after which the inter-
nal and more fpungy quot;Pm can laft but a littk while.

Drop which rBoft other Kinds of Salts form
before they fhoot. Thefe Spiculce proceed
and lengthen in different Direftions, and
crofs each other at various Angles, ^^ a a
and b b fhew, Plate VI.

Some of thefe Spicule are very deeply
ferrated, or look rather like the Ends of
bearded Darts or Arrows placed over one
another, as reprefented at c

A Kind of Star-like Figure will be found
here and there amongfl the Spiculce, appa-
rently compounded of the above-defcribed
bearded Points, and mofl: commonly, like
them, more opake than the other Shootings :
a few of thefe appear alone, and others are
formed at the Ends of the Spiculce, as at d.
Some likewife of the Spiculce, after a while
begin to fpread, and fhoot forwards, in an.
irregular Tvianner of branching, towards the
Middle of the Drop, as at g g. Other Fi-
gures arife at a Diflance from the Edge of
the Drop, with Branches dividing and fub-
dividing more regularly than the lafl defcrib-
ed; (feeY.)

During the Procefs, Clufters of hexago-
nal Planes arife in the vacant Spaces, fome
regular, others with unequal Sides, fome
perfeftly tranfparent, others with a fmall
Degree of Opacity, as at e. Thefe lafl Fi-
gures, which are indeed the proper Cryfla-
lizations of the united Salts, will remain in-
tire upon the Glafs, after all the other Con-
6nbsp;figurations

Among the Spicules fhooting from the
Edges there are many flrait-lined Figures,
whofe Ends are not pointed, but flat and
fpreading j (fee a a.J Thefe are chiefly ow-
ing to the Tartar; and the Permanence of
the hexagonal Cryfials implies that they con-
tain a large Proportion of the Vitriol.

N. B. It frequently happens, when a
Drop of this Solution, heated over the Can-
dle, is placed under the Microfcope, the
Steams arifing from it fo obfcure the Objed:-
Glafs, that nothing can be feen through it,
until the Glafs be cleared with a Piece of
Wafh-Leather, or a foft Linen Cloth.

This is the Cafe likewife in examining
feveral other Solutions, as has been before
remarked.

The Flowers of Benjamin are Salts
obtained by Sublimation from a Gum
of the fame Name. Thefe Salts are fo volatile,
that on putting fome of the Gum grofsly
powdered into a fubliming Pot, they rife
with a fmall Degree of Heat into a Cover
placed over them j whence they are wiped
2nbsp;out

out from Time to Time (with a Feather) in
the Form of long flender fliining tranfparent
Bodies, and fmell very fragrantly.

They diflblve readily in warm Water ;
and a Drop of the Solution being examined
by the Microfcope, will be found a very en-
tertaining Objed:.—For,firfl:of all there arife
from the Edges clear, colourlefs, and fliarp-
pointed Cry^2i\s fvid. Plate VI. a a) which
pafling towards the Center, fpread out like
beautiful minute Shrubs, each having two
or three Branches, like what are feen b b b.
Thefe gradually enlarge and lengthen, di-
vide and fubdivide into feveral Arms and
Shoots, in the Similitude of Trees (vid. f.)
compofing all together a Reprefentation of
beautiful little Groves or Plantations. Some
however continue fliort, and fpread into a
Sort of Leaves, indented fomewhat like thofe
of Dandelion, c c. Little Branches likewife
flioot out from Points in the Middle of the
Drop, as in the Pidlure at g: and fometimes
very elegant Figures of another Kind are
formed in fome Part of the Drop, compofed
of Branches rifing (on a new Bafis) from one
another, all arched alike with an equal Cur-
vature, and having the convex Side of each
Curve adorned with many little Shootings,
at equal Difliances and of equal Lengths,
none of which appear on the concave Side of
the Curves. All this is fliewn at e.

N. B. When aiSolu-tion of this Salt has
been made fome Days, much of it will be
precipitated, and appear in Cryftals at the
Bottomquot; of the Phial : and if you intend
then to examine it by the Microfcope, 'twill
be proper firft to hold the Phial to the Fire,
or place it in hot Water, till the Cryftals
become again diflblved and taken up into
the Fluid. And moft other Solutions (hould
be treated in the fame Manner, if they have
been long made and their Salts appear pre-
cipitated : but after being thus heated they
fhouJd be allowed a few Minutes to fettle,
otherwife the Fluid will appear turbid and
unpleafant before the-Glafs, and the Con-
figurations v^ill not proceed fo well.

HEN a Solution of this Salt is exa-
mined, if much Heat be given to the
Drop, the faline Particles will chiefly dif-
pofe themfelves at the Sides thereof, in fuch
Figures as are fhewn yz a, b b-, bat with a
leifer Degree of Heat,, they will form more
within the Drop, in a wonderful Variety of
hexangular Planes, many of which are ex-
tremely

tremely thin, flat, and tranfparent (vid. c Ct
and otiier Figures in the Plate.) Some how-
ever have a coniiderahle Solidity, as the
Drawing alfo reprefents. The above Fi-
gures foon dilfolve and break away, and to-
w^ards the End of the Procefs feveral Cry-
ftals appear with fquare Bafes, in the Form
exadlly of thofe of Sea-falt, vid. d, and
thefe are more permanent than the others
were.

HIS Salt begins ftiooting from the
_ Sides, as at ^ iz,VI.) and pro-
ceeds, forming Bodies fome of v/hofe Parts
are opake and others tranfparent, of a dark-
ifti brown Colour, with Channels or Hol-
lows running from Top to Bottom, as re-
prefented b b. There are likewife other of
the fame Figures, opake at Bottom, but
tranfparent at their Tops,. and having none
of the fame Channels, in the Manner ftiewn
c c.

In fome Places of the Drop the fame Kind
of little Hillocks are feen, adorned with

furpriling Configurations moft exceedingly
minute and delicate, bearing the Refem-
blance of fome Species of the fmalleft
and moft elegant Sea Mofiquot;es. It is impof-
fible to exprefs the Beauty of thefe Figures,
which equal any of the fineft Mocha Stones :
But an Attempt to give fome Idea of them
will be found d d d.

After the above Appearances are com-
pleated, and the Procefs feems all over,
there frequently prefents a new and unex-
peded Radiation of fine Lines, at equal Dif-
tances from each other, and arifing as it
were from a certain Point, in a very regular
Order and Delineation, the Lines fhortening
gradually on either Side, fo as to compofe
all together a femicircular Figure, like that
at e., I have found no regular Cryftals of
this Salt, nor does it ufually give any Fi-
gures at all towards the Middle of the
Drop.

The Solution I made ufe of, after ftand-
ing in a Phial two or three Weeks, had
a Cruft over the Surface, which taken
out and examined by the Microfcope, ap-
peared to be a Congeries of minute Branches,
in Shape exceedingly like fome Kinds of
Coral.

quot;IHE firft Shootings from the Edges
„ of the Drop, when a Solution of this
Salt is examined by the Microfcope, very
much refemble Leaves, vid. Plate VI. a,
on the left Side of the Pidure. But thefe
very loon enlarge and lengthen as at a on
the Top of the Drawing or elfe like thofe at
a on the right Side, which not only lengthen
but fwell at their Extremities, till they ei-
ther divide into two or more Branches, after
the Manner ftiewn at d and elfewhere in
the Drop; or feeming to burft or fplit at
their Tops, pufti forth Bundles of fine^Hair-
like Filaments, and compofe fuch Figures
with bruftiy Heads as are reprefented at c :
which indeed are extremely pretty. Some
detached Leaves are ufually formed in the
Middle, together with fuch figur'd Cryftals
as are there ftiewn, amongft which a few
hear the Appearance of thofe of common
Salt.

When the watery Part feems nearly ex-
haled, all the forementioned Figures decay
and break away, except the Cryftals, which
remain fixt: and if a full Drop has been
employed, and a confiderable Degree of

Heat applied, fome curious Configurations
prefent themfelves upon the Glafs, confift-
ing of {hort ftrait Lines, fo difpofed as to
form hexangular Figures, with delicate little
Branchings therefrom, vid. e e.

'quot;Tquot;^ FIE general Appearance which a
Drop of the Solution of this Salt af-
fords when examined by the Microfcope,
may be feen Plate VII.

After the Drop has been gently heated,
innumerable Spicule rife about its Edges,
extremely flender and clofe to one another j
and amongft thefe, as well as farther with-
in the Drop, many Bodies may be obferved
pretty regularly tapering from the Middle
towards each End, fomewhat like the Fi-
gure of a Rolling-Pin, vid. a More in
the Middle of the Drop are formed Cryftals
oddly fliaped, fuch as b b and likewife
others ending pointed like a Wedge. Some
again are divided, as c; and here and there
a Cryftal of .marine or common Salt is
found, fometimes in its ufual Figure, and

fometimes having an Opening at each Cor-
ner of the Bafe, as if the Angles had been
artfully taken out. . Thefe Differences will
be underftood by examining the. Figures

^ H I S Salt fhoots from the Edges of
the Drop many fharp-pointed Spi-
culce, at little Diftances froin each other ;
after which the feveral Figures in the
Drawing (Plate VII.) form themfelves un-
der the Obferver's Eye; fome are hexangu-
lar Planes, fomewhat opake, and appear
with a confiderable Degree of Thicknefs
in proportion to their Size, as h; wjiilfl
others of the fame hexangular Planps are
exceedingly tranfparent, and have no vi-
fible Depth. Parallelograrns are difperfed
here and there, and fome Rhombi: Indeed
the hexangular Figures before mentioned
feem like Rhombi, cut off at each End.
There appear a few of the Figures c and di
and alfo of the other feveral Forms repre-
fented in the Pidure.

A Syrup made from the Berries of this
Shrub is an ufeful Purgative in Compofi-
tions; but extremely naufeous, and fome-
vv'hat too churlifti given alone, unlefs for
Perfons of veiy robuft Conflitutions.

HE Heat neceffary to put this Salt in
Adion muft be very fniall, but brifk;
otherwife it will harden into a tranfparent
Glue, without producing any Figures j
the Reafon of which probably is, that be-
inquot;- of a vifcous Nature, when more Heat is
given than is abfolutely neceffary to put the
Particlcs of the Salt in motion, the watery
Parts evaporating, leave this vifcous Juice
fo ftrong, that the Cryftals are entangled,
and cannot force their Way through it: but
are prevented from ading as they do when
the watery Parts remain, and the Fluid is
thereby rendered lefs denfe.

The Figures it produces feem all to de-
rive their Origin from Spculce, which pro-
trude and expand themfelves in the Man-
ner to be defcribed below. Moft of thefe
Spiciilct are thickeft in the Middle, tapering
to fiiarp Points at each Extremity, and are

very tranfparent; but others of them termi-
nate more bluntly, and have their Ends
opake, whilft their middle Parts only are
tranfparent, as at a, Plate VII. Sometimes
thefe pointed Bodies are fo difpofed as feem-
ingly to iflue from one central Point, and
form fuch a Sort of Star-like or Spur-like
Figure as b at the Top of the Drawing; or
elle a Figure fomewhat different, refembling
b in the Middle thereof.

But the moft remarkable of all the Figures
it produces are owing to the lengthening
out of certain of the Spiculce, whilft they
expand at the fame Time, and pufh out
again other Spiculce from their Sides, which
likewife expand themfelves into very pretty
tranfparent Forms, not unlike the Leaves of
fome Pkuits, tho' bearing no Similitude to
thofe of the Berberry an, Inftance of this
is fhewn at Others of the fame original
Spicula fhoot not fo far towards the Middle
of the Drop, but divide and expand them-
felves laterally, fpreading out into a broader
Kind of Leaf-like Figures, vid. c c c.

Am.ong the detached Cryftals in the
Drop there are many of a pentagonal Form,
and fomewhat more opake than the reft,
terminating at one End with an obtufe
Angle. They are not marked v/ith any
Letter in the Drawing, but will ealily be
diftinguiflied in looking over it.—I do not
remember this Figure in any other Salt.

The young green Leaves of the Berberry
Tree held in a Sieve over the Steam of boil-
ing hot Water, rolled up betv^een the Fin-
gers and dried carefully in an Oven not over
hot, may eafily be miftaken for a good Bohea
Tea; refembling it much in Appearance,
and making a Liquor extremely like it both
in Tafte and Colour.—This I have myfelf
experienced. .

The firft Shootings of this Salt are
for the moft part Parallelipipids, ra-
diating from a Kind of indetermined Center,
as at a, Plate VIL Some fingle ones pro-
trude themfelves forwards, widening at the
Ejctremity, and forming Figures like thofe
at b. Some curvilinear Forms flioot alfo
from the Sides, with flat Terminations, as
at c and others ending with fliarp Points,
as d. A few hexagonal plane Cryftals, as
alfo fome Shuttle-figured Spiculce arife to-
wards the Middle of the Drop, both which
are fliewn zte.

I know not any Salt whofe Shootings are
fo extremely pellucid as thofe we are now
defcribing : For notwithftanding they have
onbsp;a con-'

a confiderable Degree of Thicknefs, they
appear more tranfparent than the cleareft
Glafs, and would almoft evade the Sight,
were it not for the faint Shadows caft by
means of that Thicknefs.

Tovv^ards the End of the Operation the
empty Spaces are filled up with Shootings
from fome of the moft detached Parallelo-
■ grams, which protrude themfelves forwards,
dividing and iubdividing as at f, and that
fometimes to fuch a Degree of Thinnefs
and Slendernefs as to have the Termination
of their Extremities loft to the Eye by rea-
fon of their exquifite Tranfparency; this
may be conceived by confidering the Fi-
gure^.

'T^ H E few Shootings which this Salt
A produces at the Edge of the Drop
are of no regular Figure, but refemble thofe
at a, Plate VII. The whole Area of the
Drop becomes quickly filled with great
Numbers of quot;Rhombi, of different Sizes, ex-
tremely thin and tranfparent, vid. b. Some
of thefe enlarge greatly, and acquire a con-
fiderable Thicknefs, forming themfelves in-
to Solids of many Sides, as c c. Near the

Conclufion fome Ciyftals of Sea-falt arc
formed, z^ d d and likewife a few odd tri-
angular Figures, fuch as are delineated at e:
Thefe and the Sea-falt remain, but all the
other Figures break away and foon become
deftroyed by the Air.

npHIS Salt begins fliooting from the
JL Edge with a Sort of Rhombic Spicu-
la, as at a, Plate VIL Some four-branched
Eigures like thofe of the Vitriols do here
fometimes arife, but moulder away before
their Ramifications are compleated, leaving
their Stamina in the Manner reprefented
bb. The Middle of the Drop is ufually
overfpread with great Numbers of Parallelo-
grams, fome exceedingly tranfparent, being
mere Planes; having fometimes one, fome-
times more of the Angles canted, in fuch
Sort as to produce pentagonal, hexagonal,
iifc. Figures. Others have much Thicknefs,
and form Parallelipipids, Prifms, ^c. as
at c. Some of the plane Figures now and
then protrude an irregular Kind of Shoot-
ing, appearing very odd and pretty, vid. d.

ON giving a fmall Degree of Heat to a
Solution o-f this Salt, Figures will be
produced from the Edges of the Drop, at
pretty large Diftances from one another,
running on in a ftrait Diredion, and be-
coming gradually larger and more clubbed
at the End towards the Center of the Drop,
but terminating in ibarp Points at the End
that is next the Edge : which is a Singu-
larity peculiar to this Salt.—Thefe Figures
are curioufly jagged or indented on every
Side from End to End, vid. Plate VIII. b b^
Some few however amongft them flioot out
from their Sides others of the fame Kind,
and thefe again other ftill fmaller ones j but
both in the primary and fecondary Branch-
ings the Shoots appear always on the fame
Side, as the two Configurations d d may
lerve to ftiew.

In the Middle Part of the Drop, and
wherever there are Vacancies, two Sorts of
regular Cryftals are formed, differing each
J^fom other both in Size and Shape. The
larger Kind are folid, and feem to be Tetra-
nedra having their uppermoft Angle and the
Edges cut off, and of thefe fome are redti-
hnear and others curvilinear. Their Pro-
duction

174 ^^^^ of Butcher s-Broom.
duftion is à very entertaining Sight: for
amidft a.violent Agitation in the Fluid, num-
berlefs Atoms being feen hurried in all Di-
redions, they rife on a fudden diredly up-
wards from the Bottom, in the fame Shape
exaftly as juft now defcribed, but fommute
as only to be difcernable by the firft Mag-
nifier, and then they increafe in Bignefs every
Inftant, under the'Eye, till they appear as
large as in the Pifture ; where zt c c and m
the Middle of the Drop feveral of them
are ftiewn.—The other Sort of Cryftals are
very minute, being when view^cd through
the third Magnifier not larger than Carra-
way Seeds; they are moftly Rhombs or
Rhomboids, fome of which have the two
oppofite acute Angles cut off-; there are
befides fome Squares and Parallelograms,

After every thing feems over, and all we
have been mentioning begins to break away,
it frequently comes to pafs, that the patient
Obferver is prefented with fome moft-ele-
gant Configurations, compofed of many long
Lines, perfedUy ftrait and parallel to each
other' every lecond or third whereof has
at one End a folid Cryftal ftiaped like the
Head of a Spear or Javelin. All the Lines
have alfo on one and the fame Side Num-
bers of fhort Lines, ifiTuing out at right An-
gles, and at pretty equal Diftances, to about
half as far as the long Lines are feparated

neral are bounded at their other End by a
fingle Line, or Bafe, that makes a right i^ri-
gle to them all: a little Variation is how-
ever produced, by here and there a fhorter
Line that runs parallel to this Bafe.—The
above Defcription will be underftbod bycon-
fidering the Configurations e e.

H E firft Shootings of this Salt^from
the Edges of the Drop appear of a
confiderable Thicknefs in proportion to their
Length : their Sides are deeply and fliarply
jagged or indented, being made up of many
fomewhat obtufe Angles; and their Ends are
pointed with Angles of the like Kind. What
I now defcribe are the fingle Shoots at a,
Plate VIII. But other Shoots frequently
branch out from thefe original ones, and
they again fend forth others, making all to-
gether a very pretty Appearance, vid. b b.—
Thefe laft Configurations in their Figure and
Difpofition bear a near Refemblance to thofe
of Butcher s Broom, ftiewn 2X d d: but are
larger and more deeply indented.

The Cryftals of this Salt are very different
from one another, confifting of Squares,
Rhombi, Parallelograms, equilateral Hexa-
gons,

gonSj fame of the Figures at f f in the But'
cher s Broom, a Sort of Shuttle-Uke Forms,
and feveral irregular Bodies j all of which will
be heft conceived by a View of them at c.

A fmall Degree of Heat given to the D rop
produces more of the Configurations, a great-
er Heat more of the Cryftals,, many of which
are at firft triangular, but foon lofe that
Shape : and indeed the whole is very fpee-
dily deftroyed by the Air.—This and the
Subjeâ: immediately preceding exhibit no
Cryftals of marine or common Salt.

IF a moderate Degree of Heat be given to
a Solution of this Salt, its firft Shootings
will be from the Edges of the Drop, in ften-
der tapering Figures ending with very ftiarp
Points, but at confiderable Diftances from
one another, and confequently not extremely
numerous : along with thefe are likewife
formed other Figures nearly of the fame
Kind, but intirely detached and farther with-
in the Drop, and contrary to the former, in
the Circumftance of having their thicker
Ends towards the Center of the Drop, and
the ftiarper pointing towards its Edge.
They are compleat Figures, and refemble
Needles, or rather that Sort of Nail called a

Bfadi which has its Head or larger End flat.
Both thefe are {hewn at a, Plate VIII.

When a little more Heat has been given,
other Spiculce are produced from the Edge,
whofe Ends fpread on either Side, and then
terminate in a Point: and which have all
along their Sides triangular pointed Cryftals,
not oppofite to one another, but placed al-
ternately, fo as to reprefent a Zigzag with a
Line drawn through its Middle, vid. The
regular Cryftals of this Salt are produced in
the Middle of the Drop, being either Hex-
agons or Rhombi, as at c.

When the Moifture is nearly exhaled,
there are fometimes feen to ftioot from, or
rather under the Spiculce, upon the Plane of
the Glafs, a Reprefentation of Leaves, very
fmall at their firft Appearance, but increafing
gradually to what is ftiewn at d.—Thefe I
have feen but twice.

A violent Agitation may be difcovered in
the Fluid by the firft Magnifier, during the
whole Procefs, but chiefly at the Beginning,
and extremely minute Cryftals rifing from
the Bottom.

Oil of Tobacco is a ftrong Poifon to many
Animals: 'tis faid a Thread wetted there-
with, and drawn by a Needle through the
Skin on the Back either of an Eel or Viper,
^ill make it die immediately. This I have
never tried.

rrs H E Cryftals of this Salt (for it (hoots
X out no Configurations) are of diffe-
rent Sizes and Figures, difperfed every where
about the Drop. Thofe near the Edges are
very minute tranfparent Parallelograms, ap-
pearing in great Numbers, as a a, PlateYlU.
In the Middle arife larger Cryftals, ftiaped
exaaiy like thofe of marine Salt, b b. There
are alfo much larger cryftaline Bodies, form-
ed here and there, having a confiderable
Thicknefs and Solidity, and confifting ot
Hexagonal and Rhomboidal Planes, vtd. cc.
It produces likewife fome odd figured Bodies,
which may be feen at d d.

*oiz. plain Rhomboids, having one or more
of their Angles very much elongated, (fo as
to be fometimes twice or thrice the Length
of the Rhomboids from which they iffue,)
Rhombi, Squares, Parallelipipidons, and
Hexagons with unequal Sides, or rather
equilateral Triangles with their Angles cut
off. In fhort, the Figures of this Salt will
much better be comprehended by applying
to the Pifture, Plate VIIL than by any De-
fcription which can be written.

At the Beginning many fine Spicule
of different Sizes, appear at and about
the Sides of the Drop, along with other flen-
der Bodies fomewhat fwelling in the Mid-
but fharply pointed at each End, vid.
« Plate VIIL Triangular folid Cryflals,
and various other Figures, are alfo formed
^ere and there as reprefented in the Picture,
f ut the mofl remarkable Part of this Sub-
ject, is a very elegant Sort of Configuration
towards the Middle of the Drop, as at ^;
and likewife Shootings of the fame Kind
from its Edge, that refemble the Branches
of fome Plant, rifmg fmgle, with Leaves re-
N 2nbsp;gularly

gularly difpofed on both Sides of each Stent, gt;
as fhewn by the other b.—In the Middle of
the Drop at c are Figures of another Form,
■which are very lingular and pretty. Thefe
all break away and become confufed very
foon after they are formed

ON the Application of a very fmall De-
gree of Heat, Salt of Hartfhorn flioots
near the Edges of the Drop, into folid Fi-
gures fomewhat refembling Razors or Lan-
cets where the Blade turns into the Handle
by a Clafp, as at d. Plate IX. This Appear-
ance is however wholly owing to the Jundlion
of a fmaller and larger Body at their fmaller
Ends, either a right or an acute Angle, as
will be evident on confidering fome of thefe
Bodies that appear fingle.

The Configurations of this Salt are pro-
duced with great Velocity, and are Figures
fomewhat opake, fliooting from the Edges
of the Drop, on both Sides a main Stem,
and with a Kind of Regularity, rugged
Branches like thofe of fome Sort of Coral,
vid. a a. But fometimes inflead of Branches
on both Sides the main Stem, fharp Spiculie,
fome plain and others jagged, are protruded

As the Fluid exhales, and the Attradion
of the Particles becomes more ftrong, fome
one of the branching Figures generally ex-
tends to a great Length, producing on one
Side Shoots that are rugged and irregular
Hke thofe in the fmaller Figures at a a, and
on the other Side a curious regular and de-
licate Sort of Branches, refennbling thofe of
fome Plant, with elegant fmall Leaves in the
Manner ftiewn at c.

A Solution of this Salt ftioots from the
Edges of the Drop long Parallelo-
grams in the Manner of Nitre, but with this
fJifference, that Nitre produces folid hexa-
gonal Pillars, cut off obliquely at their Ends,
in the Figure of a Chifiel, whereas thefe are
^nly plain fuperficial Panallelograms, whofe
Ends are flat, as a a, Plate IX. But in other
Places along the Sides of the Drop folid An-
g|es are formed, that are feemingly the Ru-
diments of common Salt, (vid. b.J though
neither this nor Salt of Hartfliorn afford any
Tegular Cryftals of common Salt.

Some of the Parallelograms increafe much
in Size, and fpread themfelves in the Mid-
dle, fo as to change their firft Figure, and be-
come three or four Times bigger than the
reft; and thefe have a dividing Line that
runs through their whole Length from End
to End, whence ilfue other ftiort Lines, at
fmall Diftances, oppofite to one another, all
pointing with the fame Degree of Obliquity
towards the Bafe, as may be feen at c c.

Among thefe enlarged Figures fome few
Ihoot ftill forward and tapering towards a
Point; butbefore they form one, fwell again,
and begin as it were anew : and thus they
proceed feveral Times before their compleat
Figure is finiftied, which is at laft a Kind of
long fharp-pointed Body, compofed of more
or fewer Joints as at dd.

After the whole Procefs feems at an End,
many fmall Branches form themfelves on
the Surface of the Glafs, as in the preced-
ing Salt (fee the Pidure,) though their
Figure is not juft the fame. — All the
above defcribed appear when a very mode-
rate Degree of Heat is given, and the Drop
is applied to the Microfcope as foon as any
of the Salts cryftalized are feen white about
the Rim. But the Figures i, 2, 3, 4, 5, 6,
are the regular folid Cryftals of this Salt,
when it is let diflblve in the Air, and no
fleat at all is given,

'T^HIS Salt ilioots from the Edges in a
J[_ Manner very beautiful, and diiferent
from any other Kind yet obferved. It be-
gins by ilfuing from the extreme Edge of the
Drop in many Lines parallel to one another,
but in a very oblique Diredion to the Line
that borders the Drop; and other parallel
Lines are produced from thefe, in an Angle
fomewhat more than right to them, the An-
gles of which are not fharp but rounded,
acd, Plate IX. Many tranfparent Paral-
lelograms of various Length and Size are
formed by thefe Lines, fome v/hereof after-
wards fhoot forwards into long Spikes which
fpread at the Sides with irregular Edges, as
at dd. In the mean while other fhort Lines
proceed outwards from the very Edge of
the Drop, in a Diredion quite contrary to
thofe we fpoke of firfl, making the Border
of the Drop appear very prettily ferrated or
J^inged, as may be feen at the Bottom of the
Configurations acd. Another Sort of re-
gular Figures are likewife produced from the
^ides of the Drop, in the Manner of thofe
bo. When the Operation is nearly ended
there arife Abundance of long Spiculce that
range themfelves fomewhat in the Form qf

Plants, filing up moft of the vacant Places
in the Drop as the Pidture ftiews. This
Salt has but one Sort of regular Cryftals,
which is hexagonal, and appears as at e.

WHEN People get what they call a
running Cold, it is not unufual for a
thin clear Humour to be difcharged through
the Noftrils, in fo confiderable Quantity as
to wet feveral Handkerchiefs, and even tcr
fall from the Nofe in Drops, if not pre-
vented by frequently wiping it away. This
Humour is what I mean by Rheum.

Being myfelf very fubjedt to this Diforder,
•which is commonly preceded by a Senfa-
tion of Fulnefs and Rigidity in the Mufcles
of the Head and Face, and attended with
much Heat, Rednefs and Sorenefs of the
NoftrilsandParts immediately adjoining, du-
ring the Difcharge, (which continues com-
monly three Days, at the End whereof it ber-
gins to thicken and become lefs acrid:) I was
defirous to know whence this limpid Hu-
mour could produce fo much Irritation and
Uneafinefs; and as a very little Confideration
made me fuppofe it muft be owing to its be-
ing loaded with pungent Salts of fome fort
9nbsp;or

cr other, I took the firft Opportunity of ex-
amining it by the Microfcope, and had the
Pleafiire then, and many Times fince, to find
my Conjeâture confirmed by undeniable De*
monftration.

For this Rheum is fo faturated with Salts,
that a Drop on a Slip of Glafs will foon
fhoot in a very beautiful and furprifing Man-
ner, either with - or without Heat : but if
heated to about the Warmth of Blood, and
then placed under the Eye, many lucid Spots
or rather Points will be feen rifing, and in-
creafing gradually, till their Form ihews it-
felf to be quadrangular, with two tranfparent
Diagonals croffing one another, fee a and d d,
Plate IX. Thefe Diagonals fhoot foon af-
ter far beyond the Square, protruding other
Lines, at right Angles, from their Sides;
(vid. c c.) which other Lines produce flill
fmaller ones from their Sides alfo, in the Or-
der of the firft ; and thus they go on to form
Configurations, whofe Elegance of Beauty
nothing but feeing them can give an adei-
tjuate Idea of : tho' till the Reader can him-
felf make the Experiment, a Reprefentation
of their general Figure is fhewn h b, and
m other Places of the Drop : where great
Numbers appear, in their feveral Gradations,
and after their ufual Manner, filling up al-
moft the whole Space,

The fine Branchings in a little whije break
away, but the central Squares remain like

d i/.—Some Figures at their firft Beginning
rife in the Shape of Crofifes, which Ap-
pearance is owing to the Shootings, from the
Corners of the little Squares, before they
are large enough to be vifible even by the
deepeft Magnifiers. The Number of main
Branches in each Configuration is moft com-
monly four, but fome are found with five or
more : the Branches lilcewife are fometimes
curved; but thefe two Cafes I take to be ra-
ther accidental than,natural.

When a Drop of Rheum is fet to cryfta-
lize without any Heat, inftead of branched
Configurations over the whole Area, as in
the above Defcription, fuch are formed only
in the Middle ; but about the Edges Plant-
like Figures are produced, ftiooting feveral
Stems from one Point, and refembling a
Kind of Sea-Mofs, vid. E. Branchings
fomewhat of this Kind are ftiewn in Salt of

Thefe Experiments fliew, that upon tak-
ing Co:d the Humours become overcharged
with Salts : how they get there, and by what
Means they may be difcharged, is a Matter
well worth Enquiry j but fuch Difquifitions
muft be left to the Gentlemen whofe im-
mediate. Profeflfion it is to ftudy the various
Diforders of the human Body and their Cure.
I may however prefume to fay, that as all
Solutions of Salt become gradually weaker,
and may be rendered quite infipid by th^
quot; ^nbsp;^nbsp;Affquot;ufiou

Affufion of a watery Fluid therefore, in
Cafes of this Nature, the frequent drinking
of warm Gruels, Teas, and fuch fmall watery
Liquors, muft in like Manner gradually di-
lute, feparate and difperfe the acrid Salts,
and be probably the moft ready Means of
carrying them off either by Urine or Perfpi-
ration.

^ere. May we fuppofe thefe Salts to
have been abforbed from the external Air at
the Time of catching Cold or to have ex-
ifted previoufly in the Body, tho' flieathed
and harmlefs till let loofe, put in Motion and
rendered acrid by the retained Matter of Per-
fpiration : as feems to be the Cafe in moft of
the animal Juices when tending to Putre-
fadtion ?

• Mr. Freke fays, in his EJfay on the Art of Healings
where he fpeaks of taking Cold; quot; tho' every one know«
quot; that Colds proceed from receiving the Air into our Bo-
dies improperly, yet few confider the State of the Air,
quot; as abounding at one Time with all the Means of reftoring
Health to us and ail the reft of the Creation, and at
another as containing in it the Caufes of Plagues,
quot; Peftilence, and Famine, by its occafioning; Death tlt;gt;
Cattle, and Blights (o all the Fruits of the Earth.quot;
Pagea 147, 148.

CAMP HIRE is a fort of refmous
white Subftance, either exfuding from
certain Trees in the Iflands of Borneo, fa-
va, Japan, and other Parts of the Eaji-
Indies, or intermixed with the woody Fibres
in the Bodies and Roots of fome Trees
growing in' thefe Countries.—It is not fo-
luble in Water, but diflblves readily in Spi-
rit of Wine, from which faturated therewith
my Experiments have been all made.

If any Heat be given it muft be very
gentle, and the Microfcope and Eye ap-
plied as foon as poftible; for the Shootings
form fo quick they will otherwife efcape
the Sight. They radiate from a Center,
either with fix or four, rarely with five
Branches, whofe Length is nearly equal;
each Branch is feather'd with fine Lines
that diminiih gradually to a Point, whereby
the Figures have greatly the Appearance of
Flakes of Snow j and the Points of fome
filling the Vacancies between thofe of
others, fmall are the Spaces that are left
uncovered. Some few fingle Branches are
produced about the Edges of the Drop. A
pretty good Reprefentation of thefe very de-
licate Configurations may he feen in the Xlth
Plate.

Of Camphire.
' If no Heat at all be applied there will
be more Time to examine the Configura-
tions ; nor even then will much Patience
be required, for the Camphire and Spirit of
Wine are both fo volatile, that if the Drop
be fpread thin, they will foon begin to
form, and quickly after they vanifh quite
away.

Camphire is of great Service when by any
Accident too large a Dofe of Opium has
been taken.

This fweet-talled Salt is the Concre-
tion of a Juice ilfuing from a kind
of Afh Tree during the Heat of Summer :
that from Calabria is accounted beft. It
eafily difllblves in Water made fomewhat
bot, and a Drop of the Solution is a very
pretty Objeét for the Microfcope.

Its firft Shootings are Radiations from.
Points at the very Edge of the Drop : The
radiating Lines appear opake, but extreme-
ly flender, vid, a a a, Plate XI. Amongft
thefe arife many minute tranfparent Cor
lumns, whofe Ends grow wider gradually
as they extend in Length, and terminate at

laft with fome Degree of Obliquity, bh.
All the Figures round the Edges being
formed in Clufters, and making but half a
Circle, bear a near Refemblance to Bundles
of fpun Glafs.

Some few Figures radiating from a Cen-
ter every Way, and circumfcribed by an Out-
line, are produced within the Drop, in the
Manner fhewn

But the moft furprizing and elegant Con-
figuration is compofed of many Clufters of
Radiations fhooting one from another over
great Part of the Drop, and making all to-
gether a Figure not unlike a certain very
beautiful Sea-Plant. Vid. C. The regular
Cryftals may be feen at e.

The Manna, I examined was, I believe,
genuine; but I am told a great deal is made
abroad, and fome in England, by an artful
Compofition of Honey, Glauber % Salt, and
perhaps fome other Ingredients. A late
Writer fuppofes they make it abroad of Ho-
ney, Sugar, and the Juice of a Tithymal or
Spurge It is worth obferving, that in

The Vegetation of Met ah. 191
the Midft of the largeft Flakes of Manna
little Twigs are frequently found, not thick-
er than Straws, round which the Manna
feems to adhere as Tallow does round a
Wick that is dipped therein.

N. B. I fhould here diredt an Examina-
tion of Sugar, but could never find a
Way of bringing it to fhoot or cryfta-
lize before the Microfcope. All other
Salts after Evaporation will fhoot their
Cryftals in a cool Place, but Sugar re-
quires a hot Stove to make it cryfla-
lize. The Figure of its Salts candyed
may be feen in Plate xiv. of the Mi-
crofcope made eafy.

After what has been already fhewn
and defcribed, the confiderate Reader
Will be at no great Lofs to judge of v/hat
Writers commonly call the Vegetation of
Metals, and the Rejifcitation of Plants, both.
Which i fhall treat of briefly.

^tfnt likewife mentions the adulterating of Mania with
^ogar and the Leaves of Seua : but adds, that this Fraud
lt;^ifcoTers itfelf by its growing foft and liquefying.

When any Metal is diffolved in a Meh-»
ilruum. Multitudes of its feparated and very
minute Particles are fufpended in the Men-
ftruum, as are likewife the Particles of its
Salt or Vitriol. In this Mixture, when fet
to reft, many of the fait or vitriolic Par-
ticles are brought together, after a while,
by Precipitation and Attradion, carrying
with them Particles of the Metal; and form
Cryftals, in Figures peculiar to the Metal
diffolved : viz. Lead produces Cubes, Tin
quadrilateral Pyramids; Copper produces ob-
lique-angled Parallelipipids, and Iron rhom-
boidal Cryftals. This is the Cafe of one
Metal diffolved ftngly in a Menftruum with-
out any Mixture j and no farther Altera-
tion happens by keeping, than that more
Cryftals will form like the firft, or that the
firft become enlarged, by the Precipitation
and Attradion of more of the vitriolic Salt:
Perhaps too fome of the metallic Particles (if
it has been over-charged) will be foUnd at
the Bottom of the Fluid, though great Part
of them will always remain fufpended.

But if different Metals or metallic Sub-
ftances be diffolved in the fame Menftruum,
or in different Menftrua, and afterwards
mixed together: or if other Fluids be
poured into any Solution of a Metal or Mi-
neral, the fufpended metallic and vitriolic
Particles, having different Degrees of At-
tra6tion and Gravity, are precipitated and

Ettradled by one another in a Variety of
complicated Diredions, and unite in Confi-
gurations extremely wonderful and pretty.
Some Produdions of this Sort have been
difcovered by Accident, and called the Ve-
getation of Metals, and many more might
Undoubtedly be found, were Trials made
'W'ith Mixtures of different metalline Bodies
^nd different Menflrua. I fhall give a few
Examples of fuch metallic Configurations.

Diffolve an Ounce of fine Silver in four
Ounces of Aqua Fortis: diffolve likewife
in one Ounce of Aqua Fortis as much Quick-
filver as it will bear : mix the two Solutions
in a clear Glafs with a Pint of Water, flop it
clofe, and after a Day it will begin to grow.

Or, diffolve in Aqua Fortis of pure Silver
one Dram; put to the Solution, of diftill'd
Vinegar and Water each one Ounce: filter,
jnd add one Ounce and a half of Quick-
«Iver; mix, and ihake the Whole fome Time,

Mouth clofe with your Finger. Standing
^uiet 24 Hours it will fhoot into Branches

various Figures,
. Monf. Flomberg tells a Way of produc-
a metallic Tree much fooner, after the
f'reparations are got ready.—Make four
^rams of fine Silver into an Amalgama
Vol. II, .nbsp;Onbsp;wifhout

without Heat, with two Drams of Quick-
filver: difiolve this Amalgama in four
Ounces of Aqua Fortis: pour the Solution
into twelve Paris Pints (about three Gal-
lons) of common Water, ftir it well together
and keep it in a Glafs Veffel well ftopped.
To about an Ounce of this Water, in a fmall
dear Phial, put the Quantity of a fmall Pea
of the common Amalgama of Gold or Sil-
ver, which ftiould be as foft as Butter.
Let the Phial ftand a few Minutes, and
you will fee fmall Threads or Filaments
rifmg perpendicularly from the little Bulb of
Amalgama, and thrufting out from their
Sides little Branches 'mYotm of aTree. The
Bulb of Amalgama will grow hard, and be
like a Pellet of white Earth, but the little
Tree will be of a bright Silver Colour.—
The ftronger the firft Water is made, the
fooner formed and fuller of Branches will

Alhertus Magnus is faid to have produced
a metallic Tree before the King of France,
while he fat at Dinner j I fuppofe by fome
fuch Method.

Diflblve Iron Filings in Spirit of Nitre,
pour on Oil of Tartar per deliquium, and a
Sort of Branches will be formed and adhere

The feeming Vegetation of Silver and
Ifon juft before defcribed, I give from
other Writers •, but this of Copper is I
helieve entirely a new Difcovery: and I
Can affirm, from my own Experience, that
It is extremely wonderful and pretty, and
«iade with little Trouble.

In half an Ounce of Aqua Fortis, let
^ bright Halfpenny, or fome feall * Piecequot;
of clean pure Copper reriiain for, about;
twelve Hours, and then take it out. Diffolve'
a little ^ick-fther in as fmall a Quantity,
sfs ^ou can of the fame or flronger Aqua
Fortis. The Solution will be white, a:hdr
like Flour and Water; at which Inflant it
^ufl be put into the firll Liquor, which will
immedii-.tely become of a lovely blue, and
throw down fomething of a v^hite Sediment,
out have very little Body or Confiflence.

, * Tho' Aqua Fortis afts on the Filinfjs of Copper fafter
nan it can on a Lump of that Metal, I have by Experience
pJnd that very fmal! Particles of Iron rubbed from the
. I'e. and mixed with the Copper Filings, do much Pre-
J'JQic to the Experiment.

^ As Fumes arifing from the Solutions of Metals in Afua
quot;»■•is, amp;c. are di/agreeable ^nd unwholefonie, 'tis advifeable
ni^e them in the open Air, and fo placed that the Wind
blow the Fumes from you.

Have ready fome Salt Ammoniac finely
powdered, whereof put in a very little at a
Time, ftirring it about till it diffolves, makes
the Mixture of a blueifh white, and gives it
a Confiflence like to Çtarch ; which Con-
dition fhews it fit for your Purpofe.

File bright any fmall Piece of Iron,
(the pointed End of a Nail about an Inch
in Length, or a fmall Nail of that Length
called a Brad, does as well as any Thing)
place it on the Middle of a Piece of clear
Glafs of two or three Inches in Width : then
ftirring the Mixture with a Quill, let a
Drop fall from the End of the Quill upon
the Iron, and wet it therewith all over (or
dip the Iron in the Mixture, before you lay
it on the Glafs, till it appears of a Copper
Colour,) add another Drop or two of the
Mixture, and with your Quill fpread it to
equal Diflances from every Side of the Iron,
an Inch or more, laying it fo thin as to
be tranfparent. Let it remain quiet in an
horizontal Pofition, and in a little while
you will difcern with the naked Eye Rami-
fications of the purefl Copper fhooting from
the Sides of the Iron, refembling the mofl
elegant Branchings feen in Mocha Stones,
(which may perhaps be produced by Mix-
tures in the Earth fomewhat a-kin to thefe)
or like fome of the mofl minute and deli-
cate Sea-moffes, They will grow continu-
ally

ally larger for Hours or Days, in propor-
tion to the Extenfion of the Liquor round
the Iron. For the Copper Particles afloat in
the Fluid, being firfl: of all attraded to cer-
tain Points in the Iron, and afterwards at-
trading one another in an orderly Succef-
fion, arrange themfelves, by the Influence
and Co-operation of the Salts wherewith
they are now joined, in fuch Manner, as
to compofe hy juxta-pofition a Refemblance
of the mofl: regular and beautiful Vegetation.
And this Attraction and Formation of new
isranches feems to go on, until all the Cop-
fer Particles in the Fluid are attraded and
difpofed by one another in the fame wonder-
ful Diredion and Order.

Left I fliould not have expreflbd myfelf
with fufficient Clearnefs to be perfedly un-
derftood, I have given a Drawing, taken
With confiderable Exadnefs, of one of thefe
^roduftions, which now lies before me, and

^nies from the great Difference in the
St en tb and Manner of the Aqua tr^
^eing prepared at diff^erent Shops, and even at
^ 3nbsp;the

the fame Shop at different Times * : which
is the Reafcm I could never exadly afcsrtain
by Weight the juft Proportion of the Mer^-
ctiry and Salt Am-moniac that depending
on the Strength and Cqmpofition of the
Aqua Fortis, iind therefore will admit of no
other Rule than obferving the Colour and
Confiftence of the Mixture, which if not
white enough wants Mercury, and if too
thin wants Salt Ammoniac, or both. But
as neither of thefe muft be in Quantity to
weaken much the Solution of Copper, 'tis
advifeable to ftir them in by a very little at
a Time. As much of the Solution of Mer-
cury as may amount to about Part of the
Whole, and four or five Grains of Salt Am-
moniac to half an Ounce of Aqua Fortis, is
ufually near the Mark. If right, after ftand-
ing a little, a thick white creamy Matter
rifes to the Top, a white Sediment foils to
the Bottom, and the Middle is a fine tranf-
parent blue Liquor. When ufed it muft be
ftirred together, and employed before it Sepa-
rates : and when fpread upon the Glafs it ap-
pears of a bleuifti white; which Ground is

* Some Jfua Fortis 1 bought became in difiblving Cop-
per not of a blue but of a green Colour; but on putting ia
the Mercury it changed to a moft lovely blue, and made the
baft Mixture I ever had ; for it might be feen to vegetate in
a Minute's Time : and produced, in a few Hours, vigorous
Branches of an Inch in Length. But there is fome Nicety re-
quifite in the Management of the Mercury ; for the Minute
it it diflblved by the Jqua Fortis, even before the Fermenta-
tion is quite over, it muft be mixed with the Solution of Cop-
per, or elfe it will concrete into a white Subftance like Salt,
and never mi-x intimately with the Copper Solution.

fo fine a Contraft to the Colour of the Cop-
per, that when the Branches are forme it
ooks like the fineft Mocha Stone: and a
Jeweller to whom I ihewed one of thefe
Produdions told me, a Stone like that would
be worth an hundred Guineas.

This Experiment feems of great Impor-
tance ; ferving to explain how Ramifications
of a like Appearance are produced, either on
the Surface or in the Fiffures of Slate, Flints,
Agates, Mocha Stones, Florentine Marbles, amp;c,
and perhaps even in their very Subftance at
the Time of their Formation, by the Inter-
mixture of faline and metalline Particles; and
alfo how Metals, diflblved by and incorpo-
rated with the faline Juices of the Earth are
formed into Branches and feem to vegetate
It was difcovered, accidentally, by the very
ingenious Mrs. Colembine, of the City of Nor-

* Of this Kind I fuppofe the Ramifications of Stiver, Cop-
per, and Iron to be that are met with oftentimes in Mines ;
either incorporated with the Stony Bed of the Metal, as in
the capillary, vegetative, or arbofefcent Sil'ver Ore from
Poio/i, or in Shootings or Branchings out from the Ores
themfelves : in the Manner of an Iron Ore defcribed by
Doaor Woodujard, (Vol. I. Clafs IX. Part IV. Nquot; 85.)
having very fine Shoots or Efflorefcencies ; from a perpendicu-
lar Fiifure in a vaftly high Mountain in Cumberland ; where
he fays, great Numbers of much finer Shoots than that in
his Polfeffion, (but fo brittle and tender he could not pre-
serve them) rofe like Vegetables, with a fingle Stem, which
parted afterwards into feveral Branches, of all Sizes, to the
Height of near two Inches. The Stems were round, and
fo were the Branches ; but towards the Extremities they
were fo jagged as to refemble common heath. They were
exaflly of the Complexion of Iron, a dulky red with a
Caft of blue.

ivich, in her Search after new Colours, from
Copper, for painting in Miniature. The
Scarlet Dyers ufe in their Buhnefs Aqua
Jrortis faturated with Tin, and make no Se-
cret of it; but one of that Trade, who is
thought to excel in the Richnefs of his Scar-
let, prepares his Aqua Fortis after a Manner
known only to himfelf. In fome of this
Mrs. Colembine diffolved Copper : and hap-
pening to leave a Piece of Iron in the Mix-
ture, ihe was furprized with the Branchings
from it, and fhewed them to my very inge-
nious Friend and Correfpondent Mr. William
Arderon, F. R. S. who by her Defire fent an
Account thereof to me, (in fune iJSi) and
withit fome of the fame Aqua Fortis.^ where-
into I put an Halfpenny, and let it remain
four or five Days according to his Diredtions;
in which Time the Aqua Fortis acquired the
Confiflence of Starch of a pale blue Colour j
and on applying it to a Nail, in the Manner
defcribed already, it might, in a very few
Minutes, be feen to fhoot out Branches, that
would continue growing five or fix Days, ac-
cording to the Extenfion of the Fluid j and
in numberlefs Trials it never failed once.
The Branches were eividently of a pure and
finely coloured Copper, rifingabove the Fluid,
exadlly regular, and perfectly difliindt and
feparate; as the Drawing, which was taken
from a Produftion by the fame Liquor, that
had been growing four Days, will fhew.

and pale, with a flight Teint of a pearly Co-
lour, was fuppofed to be only faturated with
Tin : but on trying Tin with other Aqua For-
tis, and making Experiments with Aqua
Fortis prepared by other Scarlet Dyers, we
found ourfelves difappointed and the Vege-
tation very imperfeét.

Aqua Fortis bought at feveral Shops in
London, corroded, or rather burnt the Shav-
ings of Tin, with great Fermentation, Heat
and Violence ; reducing them to a white
Pafte-like Subftance, that lay at the Bottom
and left the Liquor perfeâly colourlefs : and
when the Copper was afterwards put in,
conduced not at all towards giving the Mix-
ture a Confiftence, or promoting the Branch-
ings out; whereas the Tin in Mrs. Colembine\
Aqua Fortis was kept fufpended, threw down
no Sediment, and thickened the Mixture.
But as that Aqua Fortis can not be got by
People diftant from Norwich, many Endea-
vours have been ufed to produce the fame
Effect by other Means : and we luckily found
it might be done by the Method juft now
defcribed. We difcovered alfo, in making
Experiments without Number on this Oc-
cafion, that different Kinds of Branchings
equally furprizing and beautiful may be pro-
duced by different Mixtures. Viz.

Aqua Fortis faturated with Copper, and
applied to a Nail, will without any Addi-
tion flioot forth very pretty Branches, after
ftanding quiet a few Hours, if a due Pro-
portion

A like Solution, with the Addition of Salt
Ammoniac will (hoot fooner and ftronger.

If fome Nitre and Alum powdered, and in
equal Quantities, be put to the fame Solution
of Copper, inftead of Salt Ammoniac, Branch-
es will be produced, of quite another Fa-
fhion and Charader.

Diffolve 7 or 8 Grains of Tin Shavings in
half an Ounce of Spirit of Nitre : this will
be eftedted without great Ebullition, and the
Metal be intirely fufpended. Put into the
Solution a clean Halfpenny, which take out
after 12 Hours; then add a few Grains of
Salt Ammoniac,' putting it in by little and
little, and trying the Mixture from Time to
Time. This ftioots very well.

Aqua Fortis fent me from Norwich,
(made there by Mr. Finch) ftioots very well
either with or without Tin. It diflblves Tin
without any Precipitation, and afterwards
acquires a Confiftence with Copper, like that
of Mrs. Colembine.—Y'wt Grains of Tin\NtxQ
put into 7 Pennyweight of this Aqua For-
tis : In lefs than an Hour an Halfpenny was
put into the Solution ; and two Hours after,
a Nail being dipped in the Mixture, (which
was then as thick as Staxch) and placed upon
the Glafs with fome more of the Mixture
round it, began to vegetate in five Minutes.

An Halfpenny was put into four Penny-
weight of the fame Aqua Fortis: four
Hours after a Nail v/as dipped therein, and
placed upon the Glafs, and in 15 Minutes
the Copper Ihot itfelf all round. Salt Am-
moniac added to it quickens the Experiment
and makes the Shootings ftronger.

A Solution of Copper mAqua Regia flioots
out pretty Branchings of Copper, and better
ftill if fome Salt Ammoniac be put to it after
the Copper is taken out.

Tin will diffolve and be fufpended in Aqua
Regia: it blackens the Liquor during the
Ebullition, but leaves it at laft clear without
any Precipitation.—Diffolve 7 or 8 Grains of
Tin in half an Ounce of Aqua Regia, thtn
put in an Halfpenny, which let remain 24
Hours. This Mixture will have the Con-
fiftence of Starch, and will vegetate round
the Nail; it is of a dark green Colour. 'Twill
be improved by a little Salt Ammoniac.

I could give many other Experiments of
this Nature, but the Curious and Ingenious
will be able from thefe Hints to make Dif-
coveries themfelves of a great Variety of
Branchings, by diffolving Copper in diffe-
rent Menftrua, and by adding Mercury, Tin,
Nitre, Alum, blue Vitriol (which contains
Copper,) Corrofive Sublimate, Saccharum
Saturni, Borax, amp;c. This may eafily be done,
by adding which they pleafe to a Drop or two
of the Copper Solution upon a Plate of Glafs,
and trying it wdth a Nail: and if they

like the EfFedl, the fame Mixture may then
be made in a large Quantity and kept in a
Phial to entertain them at any Time; for all
thefe Mixtures may be preferved in good
Condition many Months

It may be proper to obferve in general,
that thofe Nlixtures are the moft agreeable
which have fome Body or Conjijience j and
that fuch Confiftence is given by adding a
Soludon of Mercury to the Copper Solution,
and then putting in Salt Ammoniac or by
dilfolving Tin in the Menftruum before the
Copper is put in. If the Mixture corrodes
the Nail it never does well; or if it turns
green round the Sides thereof, which it will
do when overcharged with Salt Ammoniac ;
but defpair not of any Nail's fliooting till it
has lain twelve Hours.

If you can procure Aqua Fortis that will
diflblve and fufpend Tin, (not burn it into a
white Powder) the whole depends on leav-
ing it of fuch due Strength, that it may be
able to diflblve Copper enough, after it has
diflblved the Tin, and yet not be fo ftrong
as to corrode and raife Blifters on the Nail
moiftened therewith, thereby difcolouring
the Copper and fpoiling the Experiment.

• 'Tis beft to keep all Mixtures with acid Spirits in a
little Box by themfelves, and in Phials (holding an Ounce
at leaft) not more than half filled j for fome of them will
ferment and ftand in need of room; they (hould alfo have
well fitted Glafs Stopples.

On the contrary, if too much Tin be diifolv-
ed in the Aqua Fortis it becomes whitifli or
milky, diffolves not enough of the Copper,
and is too weak for Vegetation. Difap-
pointments will alfo happen if Care be not
taken in proportioning the Mercury and Salt
Ammoniac, when they are employed : and
yet the certain Weight and Meafure cannot
be laid down, from the great Difference in
Aqua Fortis.

The Nail or Piece of Iron fliould be filed
bright at the Time 'tis ufed, and its Surface
made fo even that it may come clofe to the
Glafs its whole Length. 'Tis beft to hold
the Nail in the Mixture for a Second or two,
till it is of a Copper Colour, before you
place it upon the Glafs : your Shoots will
thereby be made the flronger, as the Cop-
per Particles floating in the fmall Quantity
you put upon the Glafs, finding the Iron al-
ready covered, will difpofe themfelves more
into Branches. But doing this often will
impoverifli your Mixture by drawing the
Copper out of it : and therefore 'twill be right
to keep fome feparately for fuch an Ufe.

The Branchings pufh out to the Extremity
of the Drop, and then frequently turn along
the Edges, flill dividing into fmaller Rami-
fications, till at lafl they run into one another
and become confufed ; or elfe a yellow Tino-e
drawn from the Iron diffufes through the
Fluid and renders them obfcure; but neither
5nbsp;of

of thefe happen till the Vegetation is nearly
at an End, which is not till after feveral
Hours, and in fome Sorts feveral Days. They
may however be preferved in good Condi-
tion, by preventing any farther Aition of the
Salts when the Shootings are advanced to
their utmoft Perfedion, if at that Time the
Nail be taken away carefully with a Pair of
Nippers ; then foaking up the Liquor where
the Nail lay with a little Brufli or Rag, dip
the Glafs gently into Water, and hold it there
a few Seconds. Hereby the Shootings are
ftopped, the Branches are left upon the
Glafs in very good Order, and if another
Glafs be put over them, guarded with Slips
of Cork as àixxeamp;tà pag£ 36, they may be
kept many Years. Sometimes indeed they
will turn green (that is, grow rufty) but as
their Forms continue, it takes but little from

Tho' all thefe Ramifications are large
enough to be feen diftinftly by the naked
Eye, being frequently above an Inch in
length, 'tis very deiireable to examiné them
by Glaffes through the different Stages of
their Progrefs ; for the Microfcope difcovers
on fome of them the Appearance of Flow-
ers and Fruits, and fliews many curious Par-
ticulars not elfe to be conceived. The 4th
or 5th Glafs are beft for thefe Subjedts,
which require no great Magnifier,

Copper cannot perhaps be brought to ve-
getate foftrongly any Way as by being diffolv-
ed in acid Spirits ; but having in the Courfe
of my Experiments difcovered other Means
of bringing it to produce very elegant Branch-
ings, tho' fo fmall as to require being viewed
with Glaffes, I fhall not conceal them from
the Reader.

Diffolve as much of the bliieji and clean-
ifl Vitriol in warm Water as it can poffibly
fufl:ain. Put a veryJittle Salt Ammoniac in
fine Powder upon the Glafs Plate, to which
add two or three Drops of the Vitriol Solu-
tion. When the Salt Ammoniac is diffolved,
place in the Mixture upon the Glafs a fmall
Brad filed bright, wet it all over with the'
Liquor, and fpread the Liquor round it, as
in the foregoing Experiments ; It will im-
mediately attrait the Copper in the Vitriol,
and foon begin to fhoot out Branches, the
Form of which, as the Microfcope will fliew,

infliead of Salt Amnioniac caufes a different
Kind of Shootings.-If the Copper Solu-
tion be overcharged with Salt Ammoniac or
Sublimate it will not flioot at all, but turns
yellowifh. round the Nail. A few Trials
will fettle the Proportion, which is accord-
ing to the Quantity of Copper in the Vitriol.
An exceeding fmall Drop of Spirit of Wine
Will raife a Fermentation with the Vitriol,

but that being over before the, Nail is appli-
ed, it makes the Shootings ftronger.

The firft Principle of Alt;ftion in all thefe
Experiments is the AttraSiion of Copper by
Iron-, but that only ferves to cover the Iron
•with Copper Particles, in the Manner before
defcribed, pages 80 and 81. The Branchings
of every Sort are owing to the Agency of Salts',
which Confideration may perhaps lead to
Means of producing Vegetations from other
Metals.

'Tis hoped the dwelling fo long on thofe
Experiments may be excufed : as they are ex-
tremely pretty in themfelves, and feem to
open a Way towards accounting for many of
the moft curious Produdtions in Nature.

H E Chemifts tell wonderful Things
of the Refufcitation or Refurrediion of
Plants from their Alhes; and 1 make no
Doubt extraordinary Configurations have
been produced in very ftrong Solutions of
vegetable Salts, by the Means of Precipi-
tation and Attradion : but I Cannot help
believing that Imagination has been greatly
indulged, when they talk of Branches,
Leaves, and Flowers^ exaSlly refembling thofe
to which the Salts belong.

The famous Phyfician ^ercctanus tells a
ftrange Story of a Polonian Dodtor, who
fliewed him a dozen GlafTes hermetically
fealed, in each of which was a different
Plant, as a Rofe in one, a Tulip in another,
a Clove July-Flower in a third, ^c. When
thefe Glaffes were firft brought to View, you
faw nothing in them but a Heap of Afties
at the Bottom ; but on the Application of
fome gentle Heat under any of them, there
prefently arofe out of the Afties the Idea of
the Flower and Stalks belonging to thofe
Afties ; and it would ftioot up and fpread
abroad to the due Height and Dimenfions
effuch a Flower, and had the perfedl Co-
lour, Shape, Magnitude, and all the other
Accidents, as if it were really the Flower.
But whenever the Heat was.drawn fromjt,
as the Glafs and the included Air and Mat-
ter cooled by Degrees, fo would this Flower
fink down by little and little, till it would
bury itfelf in its Bed of Alhes j and thus it
^■vould do as often as a moderate Heat was
applied or withdrawn. 'Kireher is faid'to
have done the fame Thing at Rome. ' '

Dr. Cox gave an Account to the Royal'So-
^jety (Phiiof.TranfW lo'i) quot; that having
procured a large Quantity of Fern Aßoes,
from Fern burnt when between green and
quot; dry, he extracted their Salt in the commpa
I' Manner with Water, and obtained feveral
Pounds of Salt, after evaporatinf»- the W^a-
VoL. II.nbsp;Pnbsp;ter;

quot; ter ; the greateft Part of which, being
quot; firft dried, he expofed to the Air, that
it might become an Oil per deliquium.
The Remainder of the Lixivium which
quot; continued fluid, being filtered whilft
quot; warm, was of a very red Colour, deeper
quot; than florid Blood and moft Clarets, and
quot; exceeding ponderous. The Colour fl:iew-
ed it abounded with fulphureous or oily
Parts, and the Weight that it was highly
faturated with the faline. This ftrong
quot; Solution being put in a capacious Glafs,
quot; in five or fix Weeks depofited a large

quot; over the Bottom of the Veffel. The
quot; loweft Part of the Salt was of a dark Co-
lour, as if fome Dirt or Dregs were mixt
therewith, but the Surface next the Liquor
« was exceeding white j and there fprung
«« out of the whole Mafs of Salt, at fmall
Diftances from each other, about forty
Branches, which (excepting the Colour)
« did moft exaaiy refemble that Kind ot
Fern which is fingle like Polipody and not
«« branched, fending out feveral Leaves on
quot; each Side from one Stem. They differed
in Size, but were all alike in Figure,
quot; without the leaft Variation : only fome
quot; emitted more Leaves from the Stem than
« others; which is alfo ufual in the natural

Dr. Cox likewife adds, quot; that mixing equal
** Parts of Sal Ammoniac and Pot-Afhes, the
latter of which had a very flrong ful-
phiireous Smell, yet feemed to abound
with Salt confiderably alkalized; the Mix-
quot; ture being put into a tall Glafs Body, im-
mediately upon feeling the Heat a great
deal of volatile Salt v/as fublimed, and in
the Glafs Head he obferved, to his Sur-
prize, a Foreft in Perfpedlive of Firs, Pines,
fo admirably delineated, as not to be
excelled, if imitated, by the Pencil of the
greateft Mafter.quot;
Having left a fmall Quantity of Compound
Syrup of Balfam in a Phial, that was fet by
and forgot, with only a Piece of Paper thruft
into the Mouth of it inftead of a Cork j
When it came to hand two or three Months
after, 1 found all the watery Part evaporated
and the Sugar cryftalized at Bottom : and,
what furprized me very agreeably, the fa-
'ine Particles of the Gums and Balfams, of
^nich it was compofed, had ftiot themfelves
^fnoft intirelyr ound the Infide of the Glafs
'nal, in the moft regular and pretty Con-
^g'^u-ations imaginable j and remained fo for
a long Time afterwards

The Adivity and Volatility of Salts are
Wonderful, and I make no Doubt many en-
tertaining Experiments might eafily be made
quot;y Intermixtures of vegetable and

-nbsp;is to be hardened in the Sun and atter-
wards fet in a cold Cellar; from the above-

-nbsp;mentioned Mafs, by the Help of balt-
« petre, you will fee Flowers branch out

And fuch is the Force of Nitre, that, it
in a Glafs kept clofe Ihut^ you pour the
quot; Juices of fome nitrous Herbs on the above
Mafs, the Nitre coiitained within it be-

Configuration, derive their Figures from
the Intermixture and Operation of Salts of
fome Sort or other. For that Salts abound
every where in the Earth, either at Reft
and locked up in Minerals and other Bodies ;
or in a State of A61:ion, being diflblved and
carried along in Water or fome other Fluid,
is a Matter beyond Difpute. The finer Par-
ticles of fuch Salts being diflblved in and
rifing with the Particles of Water float
likewife in our Atmofphere in great Abun-
dance, where by Heat and Cold, by a greater
or lefler Degree of Rarefaction, as well as
by other Accidents, they at different Times
are (in the Air) brought together in greater
Quantity, or become more difperfed and dif-
fipated : whence confiderable Changes and
Alterations are produced, fuch as Freezing,
Hail, Snow, Lightning, Thunder, ^c. But
I fliall confine my Obfervations to the Ef-
f'^fts that are probably owing to faline Par-
ticles within the Bowels of the Earth or very
near the Surface thereof.

Since we are acquainted v^^ith no Dijfol-
''^snts of Metals where Salts are not prin-
cipally concerned, it is reafonable to fup-
Pofe, that in the Bowels of the Earth, Salts
J^ay likewife, when diffolved themfelves,
bave a Power of diffolving metallic Sub-
ftances ; and afterwards, on the withdraw-

^ * Vitriol, Alum, and Nitre, are fo volatile, when diffolved,
through the clofeft Cork, or between the Bottla
the Cork, tho' ever fo clofely ftopped.

inquot;- of the Fluid, of uniting with the metallic
Particles, and bringing them together in cer-
tain Figures peculiar to fuch an Admixture,
and more or lefs perfeft according to the re-
fpedive Proportions of metallic, faiine, and
other Particles. Thofe curious Ramifications
in the arborefcent filver Ore brought from Pa-
nama, which run through the Bed of Stone
wherein it lies, may perhaps be owing to the
Particles of that Metal having been diifolved
by a vitriolic Menftruum, and carried along
with it into the little Fiflurcs of the Stone j
where as the Water evaporated, the Silver
Particles were Ihot out and difpofed by the
vitriolic Salt, into Ramifications fo nearly
refembling the Configurations of Vitriol.
The Branchings of Cofper and Iron (by fome
imputed to a vegetative Principle) are pro-
bably produced in a like Manner ; and the
Reafon why Gold is feldom or never found
thus branched, but always in little Lumps
or Granulse, may perhaps be, that the Salts
which diflblve other Metals are unable to
feparate the Particles of Gold.

Rock Salt, (which differs little or nothing
from the Salt of Springs and of the Sea,)
Vitriol and Alum, (of which, and alfo of
Sulphur, the faiine Acid, Chemifts tell us,
is in all the fame) Nitre and Borax, are 1
think the only foffil or mineral Saks fpoken
of by Writers ; for Salt Ammoniac can hard-
ly be accoupted fuch. But it is impoffibls

to fay what others befides thefe the Bowels
of the Earth may contain, or how infinitely
they may be compounded and diverfified.
I fhall make no Difficulty to fuppofe the
component Particles of Spars, Cryfials, and
precious Stones have been feparated zn^i float-
ing in fome Fluid, and brought together in
the Shapes we fee them by certain Laws of
Attradlion, which in like Circumftances are
conftant and unalterable. And as uniting
in regular Order, and forming Maffes of
Figures uniform and conflant, are the diftin-
guifhing Properties of Salts, (as the forego-
ing Experiments fhew) the component Par-
ticles of Bodies thus formed muft originally
have been Salts, notwithftanding the Bodies
fo compofed are indiffolveable: nor is the
prefent fixt Condition of fuch Particles, or
the Hardnefs of fuch Bodies, any conclufive
Objedlion; for the making of Glafs fhews,
that Salts may be rendered fixt, hard, and
indifiblveable. I therefore apprehend that
all cryflaline Matter, or the Particles of
Matter whereof Spar, Cryftals, and precious
Atones are formed, is originally a Salt, ac-
cording to my Meaning of the Word ; and
J-^nncEus is I prefume of fome fuch-like Opi-
nion, fince in his Syflema Natures he places
all precious Stones, even the Diamond itfelf,

Dodlor Woodward likewife, though he
fpeaks not of this cryftaline Matter as a Salt,

imputes it to the Properties that Salts have,
when he fays, the ßootmg of any Metal pra-
ceeds generally, merely from Cryftal, comkn--^
ing with it in the ConcoBion and Formation oj
the Mafs. And again. Metalline Matter,
when pure andfmple, never ftooots into an an-
gulated Figure, nor is indeed capable of doing
that. The Bodies incorporated with Metals,
ond difpoftng them to ftioot into angulated Fi-
gures, are either Sulphur (by which he muft
mean the Sal Acidum of Sulphur) or Cry^
ftcd. quot; Iron concreting with Cryftal deter-
mines it to a rhomboidal Figure, Tin to a
quadrilateral Pyramid, Lead to a cubic Form.
If Cryftal be pure it fhoots into a ßx-ßded
pyramidal Figure, or into a Pyramid erefted
upon a Column, each with Sides and An-
gles.quot; He moreover fuppofes, quot; the Bafis of
all tranfparent Gems to be a cryftaline Mat-
ter different in Hardnefs, and coloured by
metallic Mixtures : Lead imparts a yellovV,
rin a black Copper a blue or green.
Iron a purple, an amethyftine, and various
Sorts of red. The Figures of all angular
opake Foffils are owing to the like cryftaline
Matter, but in them the metallic Matter
fo much exceeds the cryftaline, as to render
the Body opake -f.quot;

That the Shoots of Cryftals are formed in
a Fluid ftrongly charged with cryftaline
Matter, will readily I believe be granted, and
likewife that their Formation is nearly in
the fame Manner as the Formation of the
Cryftals of dilfolved Salts. But perhaps it
may be inquired in what Time this Opera-
tion is brought about; and though that
much depends on the Strength of the Solu-
tion,.and the Evaporation of the watery Part
of the Fluid, there muft certainly be a Crifs
when the Cryftals begin to form; after
which, little Time perhaps is required to
bring them to Perfedion : for, when the
jloatitig Particles come within the Sphere of
each other's Attradion, they rujli. together
unite, according to their refpedtive Figures,
andthat in a ftiort Time; as is plain in freez-
ing, and in artificial Cryftaliz-tion, which is
brought about in the fame Way.

Great Difputes have arifen among Natu-
ralifts concerning the Formation oi Corals
and Corallines under which Names Bodies
of very different Contextures, Subftances
and Figures, are I think too indifcriminately
included; their Appearance indicating not
only a Difference in Species, but even in Ge-
nus. Some infifl on their being in general

* As I think it needlefs to enter into Particulars, by
^»r«/, and Corallines 1 intend, in general, whatfoever the

the IVork of little Anitnü Is,whWik. others main-
tain that they are all Sea-Plants. There
may be found perhaps of both thefe Kinds :
but is there not a Third, I mean the ßony
Corals) whofe Produdtion may be more a-
kin to that of Minerals, and chiefly owing to
the Operation ofßiline Particles incorporated
with ßony Matter f

The Rocks in the Sea on which thefe
Corals are produced, arc undoubtedly replete
with mineral Salts, fome whereof near their
Surface, being diflblved by the Sea Water,
mufl: confequently faturate with their faiine
Particles the Water round them to a fmall
Diftance, where blending with the * ßony
Matter with which Sea Water always a-
bounds, little Maßes will be confl:ituted here
and there and affixed to the Rocks. Such
adhering Mafles may be termed Roots: which
Roots attraBing the faiine and fliony Parti-
cles, according to certain Laws in Nature,

• I call thofe Corals ßony which have a Hardnefs like
onto Stone ; and would be underftood to mean byJionyMat~
ter, that Matter which conilitutes the Bafis of fuch Corals ;
without any critical Enquiry whether it is or is not different
from that Kind of Matter whereof fome Stones are made.

Dr. Wcoa^-ward fays, quot; the true marine Coral is indeed a,
quot; ftony Subftance, and of mineral Nature and Origin ; the
quot; conltituent Matter of it i^beat off from the Rocks and
quot; Cliffs, (where the Agitation of the Sea io. great) borne
quot; thence, precipitated and affixed to Rocks, Stones, Shells,
quot; or other Things, where the Water is more ftill and calm.
*' As it is of the fame Conftitution, fo it owes its Solidity
and the Cohefion of its Parts to the fame Caufe that Stone«
and other Minerals do.quot; Hiß. Fvßb, Claß V, Vol. I.
page itq.

may produce branched or other Figures, and
increafe gradually by an Appofition of Par-
ticles ; becoming thicker near the Bottom
where the faline Matter is more abounding,
but tapering or diminijhing towards the Ex-
tremities, where the mineral Salts muft be
fever, in proportion to their Diftance from
the Rock whence they originally proceed.
And the different Proportions of mineral
faline Particles, of the jiony or other Matter
wherewith they are blended, and of marine
Salt, which muft have a confiderable Share
in fuch Formations, may occafion all the
Variety we fee. Nor does it feem more dif-
ficult to imagine that the radiated, Jiarry, or
cellular Figures along the Sides of thefe Co-
rals, or at the Extremities of their Branches,
may derive their Produdlion from Salts in-
corporated with Jiony Matter, than that the
curious Delineations and Appearances of mi-
nute Shrubs and Moffes on Slates, Stones
^c. are owing to the Shoots of Salts in-
termixt with mineral Particles ; and yet thefe
are generally allowed to be the Work of
niineral Steams or Exhalations by which
muft, I think, be meant the fineft Particles

* Let me not be mifunderftood to mean the Imprejpens of
quot;lants found frequently on Slates, Iron-Stones, l^c. for fuch
Imprejjions are undoubtedly owing to the very Plants them«
felves, whofe Figures thev bear, having been lodged in the
Matter whereof fuch Slates or Stones are made, whilft it was
i^n a fluid or foft State ; which they ferve to prove it formerly
has undoubtedly been.

of fome Metal or Mineral incorporated with
and brought into Adion by a volatile pene-
trating Acid, which carrying them along
with it into the Fiifures at leaft, if not into
the folid Subftance of fuch Stones or Slates,
there determines them to ftioot into thefe
(legmit Branchings; after the fame Manner,
and frequently in the fame Figures, as the
Farticles of Mercury, Copper, amp;c. are dif-
pofed and brought together by the Salts in
Jtqua Fortis, of which an Account is before
given, 196.

Such as believe thefe Corals to be the
Work of Infers, ground their Opinion,
(againft many feeming Appearances to the
contrary,) on the fole Suppofition that each
of their Jiarry Cells or Hollows is inhabited by
an Infetl, who therefore was the Maker of it.
I very readily believe InJeBs are frequently
found therein : for the Works of God are all
fubfervient to one another, fo as to compofe
a perfedt Whole; and as on the Earth moft
Kinds of Plants afford an Habitation for In-*
JcBs, it would be very ftrange if amongft the
innumerable Animals in the great Sea, fome
Species or other were not intended to dwell
in thefe little Cells. But without objeding
to the Difproportion between the Work and
the Workmen, and that Animals fo exqui-
fitely tender and delicate ftiould yet be able
to bring together and faftiion fuch large and
hieavy Maffes of Stone-like Matter, fince Na-
ture

turc is every where wonderful; I fhall only
remark, that were all thefe Cells filled with
Anunals, and efpccially the very large Cells
in fome Corals, to which the Animals muft
be tuppofed proportionably large, it could
fcarce have happened but that every Fifher
for Coral, or whoever had feen a Branch of
It in the Sea, muft likewife have feen thefe
Animals. Befides, at different Times, there
have been fome diligent Obfervers of Coral,
whofe Notice thefe Animals have efcaped;
which renders it probable, that though fome
Cells may be inhabited, the Generality cf
them are not. And as to forming Conclufions
from the minute Corallines, whofe Subftance
and Figure bear not the leaft Refemblance
to thefe, and infifting that becaufe the little
Veflels or Cafes found on them are the Nejls
and the Works of lnfe£ts, therefore Infedts
muft have been the Fabricators of all the
Corals; I fay, to conclude thus, is fomewhat
over hafty and unphilofophical

* The Animals fuppofed to hive/ormed Corals, or to have
fade their NeJls upon them, are, for want of knowing their
proper and dillinguifhing Charafters, called at prefent by the
general Name of Polypes ; though perhaps their Species, Size,
^nd Figure may be as different as the Corals themfelves are:
put thele Animals are defcribed by all who fpeak of them, as
having Bodies fo extremely tender that a very flight Touch
will lacerate or diforder them. They are alfo reprefented as
fixt to one Spotj with little other Motion than that oiextend*
ing their Arms or Bodies out of their Cells, ot contraiiing
themfelves and retiring therein at the Apprehenfion of Danger.
Creatures thus circumftanced feem very little capable of col-

Though, living far from the Sea, I have
never been able to examine Corallines juft
taken from thence, I doubt not the Veracity
of thofe who fay, that on placing them con-
veniently in Sea V/ater, they have by Glafles
difcovered minute Polypes in every one of
the little Veflels : but thefe Veflels or Cafes
are of a membranaceous Texture, tranfpa-
rent, and in moft Particulars intirely differ-
ent from the ßony Corals ; and even allowing
them to be the Work and Nefts of Infefts,
am not yet, I muft confefs, intirely con-
vinced that the whole Coralline is fo too ; for
in many of them a tough Stem, feemingly
of like Confiftence with that of other Sea-
Produdions acknowledged to be Plants, rifes
from a Root or what appears to be fo, and
branches out in fuch a Manner, that I be-
lieve the moft accurate Examiner, void of
any Hypothefis, would declare it to be vegeta-
ble.—In ftiort, there are wonderful Mix-
tures in the Sea; Stones, Shells, and Plants,

lefting and carrying a ßony Matter, and raißng Edifices there-
with ; and efpecially in fuch large Quantity, that comparing
the Smallnefs of the Cells wherein ihefe Creatures are fup-
pofed to dwell, with the Bulk, Solidity, and Weight of the
Roots and Branches of many of the Stony Corals, the greateft
Part of it appears qu'te unneceffary. This is direftly con-
trary to the Oecouomy of Nature (frugal though fußcient)
the Shelly Cafes of the feveral Species of Vermiculi, in th®
Tuhuli marini, the Pipe C rals, and the Habitations made
by other fmall Infcfts ; all which, like the Honey-comb, are
framed of as little Matter as poflible, thin, light and roomy,
and appear to be wha- they are. I ftiall only add, againft tne
fuppoüng alt Corals to be made by Infedts, that fome Sorts
have no Cells either on their Stems or Branches.

are frequently incrufted with the ftony Mat-
ter that gives the Subftance to Cora/; and
I make no Doubt that Millions of minute
Animals find or build them ^labitations both
on the Corals and the Sea-Plants.

But to leave a Digreffion, which is not
perhaps quite foreign to my Subjedt, and
wherein 1 would not be thought to afiirm
any Thing, but only to point out how the
Jiony Corals, which are certainly formed by an
Appofition of Particles fomehow or other
brought together, (having noFibresoxYtm^
to convey Juices for Nutrition or Increafe,
and therefore being no Vegetables) may pofi
fibly be produced with all their beautiful
Regular ty and Variety, even though on a
ftrifter Enquiry they Ihould not appe?r to
be made by Infersnbsp;tr ^ ^

The Salts of Minerals and Vegetables
floating in the Air produce a thoufand pretty
Appearances, when brought together and
concreted by Froft. I have feen, in Winter

^orts i^i Cpftah, Spars, amp;c. and he will find amongft the:,,
whofe Shootings are as regular and uniforai as thc'e of

allowed by NaturaUfts to derive their SabftLce and Form
quot;Om cryftaline Matter, combined with difffient Sorts or Pro
portions of metallic, ftony, earthy, or other Subftances I er
film particularly examine and confider the Ludus He'mnrtil
^^^ Jiarry 'wa.en Fe,„, the Eric^-formis or Hel 'Ts 'lr
Jhe vegetative S.l-.er, Copper, and Ln-ores, and II t
t'^rlyft^ured Cryftals, Spars, MarcafUes, and r^etallU

Time, formed in this Way, upon Windows,
on wooden Pales, and fometimes on the Webs
of Spiders, very elegant Reprefentations m
Miniature of Landfcapes, with Groves of
Trees, and a feeming Variety of Shrubs and
Herbs: but the moft charming of this Kind
I ever beheld ufed to be on the Glafs Win-
dows of a necefl'ary Houfe in the Country,
owing I fuppofe to the additional Inter-
mixture of animal Salts.

Copper Plates are very expenfive, and De-
fcriptions without them hardly intelligible¹
or I fliould have added many curious Ob-
fervations made on Mixtures of animal, ve-
getable, and mineral Salts (fome of wnich
tre in very few ^ Hands) as alfo on the So-
lutions of different Metals and Minerals by
add Spirits but thofe who know any thing
of Chemiftry, or will beftow a little Time m
the Study of Nature, will, I am perfuaded,
in Confequence of the Hints here given, fug-
jreft to themfelves numberlefs Experiments,
which if purfued may prove both profitable

In fhort. Salts are the aftive Principles
v/hereby Nature performs Wonders; as is

1nbsp; Partkularly the Matron of Egypt, brought thence and
given me by Dr. PocccH an alkaline Salt fermenting violently
with Vinegar (whofe Shootings are very f.ngular) from Sgt;ng
in the Inland Parts of Afia, given me by Su Hans bloane; tii
.engine Salts of mineral Springs in different Parts of the Wor d 5
tnd many other /aline Suhjiances either in their natural State,
or by human Ait extradted or compounded.

fufficiently evident from that Variety of Fi-
gures they produce, by combination with one
another, or when incorporated with Sub-
ftances of other Kinds. But this has given
Occafion for fome to objedt, that the Figures
of Salts cannot be determined, fince the fame
Acid diflblving different Bodies aflumes dif-
ferent Shapes. Spirit of Nitre, fay they,
for Inftance, having diflblved Copper, ftioots
into hexagonal Cryftals; having diflblved
Iron, into irregular Squares ; and forms tri-
angular thin Cryftals after diflblving Silver.
But waving all Difpute, which 1 fball ever
carefully avoid, does not this feem a Proof
rather of their Conftancy than their Uncer-
tainty ? for the Sliootings of pure Nitre ex-
amined alone are conftantly the lame; and
are not the Cryftals produced in Spirit of
Nitre when Copper, Iron, or Silver has been
diflblved the rem, always conftant to each re-
fpedlive Metal, though diiferent from one
another ? What greater Conjiancy than this
can pofllbly be expefted ? and would it not
occafion much greater Uncertainty and Con-
fufion were mixt 2ind unmixt Subftances to
put on the fame Forms?—It is likewife
objeded, that their F^igures vary if they are
differently prepared: And this indeed is
^e. But as with the fame Mixtures or
Management they are found to produce the
wme Cryftals and Configurations, this Ob-
jeftion has no Force; unlefs it be to Drove
VOL. II,nbsp;f .hai

that the Figures they produce are dijiinguijh-
ing and infallible Marks of their different
Degrees of Perfe6lion, and that the Micro-^
SCOPE may be of the utmofl Service to dif'^
cover Knavery and Impofition.

An Account of various Animalcules
never before defcribed ; and of many
other Microjcopical Dijcoveries.

A Defcription of the Microfcope ufed in
thefe Experiments : and of a new Mi-
crometer ferving to (hew the comparative
Size of magnified Objedls.

Though every Thing is alike eafy to
an Infinite and Almighty Being, yet,
according to human Comprehenfion, it ap-
pears extremely vponderful, that vs^e find, al-
moft without Exception, in thefe Specks of
Life whofe Minutenefs renders them almoft
imperceptible to the Eye of Man, a greater
Number of Members to be put in Motion,
more Wheels and Pullies to be kept going,
a greater Variety of Machinery, an Appara-
tus more complex and curious, a Plan feem-
^gly of deeper Contrivance; in ftiort, more
Wegance and Workmanjhip (if the Term may
e excufed) in the Compofition, more Beauty
aM Ornament in the Finiftiing, than are
^en in the enormous Bulk of the Elephant,
Crocodile, and the Whale; compared
With which, one would think them no lefs
the EfFea of a more exquifite and fupe-
nor Art, than the Movements of a Watch
^Ppear to be, on Comparifon with the
^^ heels of a Coach or Waggon.

Thefe Truths need no Proof to fuch as arc
acquainted with the Microscope, however
incredible they may feem to others : that
valuable Inftrument will fully convince us,
that All the Works of the Creator well de-
ferve our moft diligent Attention ; that Per-
fedtion appears every where j that Minutenefs
is no MarkofMeannefsj and that nothing is
fo little or fo low but that it can richly repay
our Enquiries. Hereby we are likewife
taught, that an Atom to Omnipotence is as a
World, and a World but as an Atom; in
the fame Manner as to Eternity one Day is
•as a thoufand Years, and a thoufand Yeap
but as one Day. Every Species of thefe Ani-
malcules may alfo ufefully ferve to corredt
our Pride, and prove how inadequate our
Notions are to the real Nature of Things :
by making us fenfible how little of the larger
or fmaller Part of the Creation could poffi-
bly be made for us; who are furniihed with
Organs capable of difcerning to a certain De-
gree only of the great or little, all beyond
which is as much unknown, as far beyond
the Reach of our Conception, as if it had
never been.

An Examination of the Variety and Beau-
ty of the IVorks of Nature muft afford the
moft reafonable Satisfaftion to a contempla-
tive Mind, as they ftrongly evince the Agei^'
cy and Omnipotence of the Deity. Proois
of fome all-powerful, wifcj and good Being

are indeed deducible from every thing
around us, but the extre?7iely Great and the
extremely Small feem to furnifh the cleareft
and moft convincing ; and perhaps, if duly
confidered, the FabVick of a World, and the
Fabrick of a Mite, may be found equally
ftriking and concluiive.

Glasses difcover to us numberlefs Kinds
of living Creatures, whofe Minutenefs ren-
ders them abfolutely undifcernable by our
naked Eyes, and God alone knowshowmany
thoufand Kinds there may be, ftill gradually
decreafmg in Size, v/hich it is impoffible for
Jis to fee by any Help whatever ; to all thefe,
however, we muft believe, from reafoning
On what we know, that Providence has not
only appointed the moft wife Means for
Propagation, Prefervation, and Happinefs,
but has moreover adorned them with Beauty
equal at leaft to auy thing our Eyes have ever
feen.

The fmalleft living Creatures our Inftru-
^nts can fhew are thofe that inhabit the
Waters: for though polTibly Animalcules
no lefs minute may fly in the Air, or creep
npon the Earth, it is fcarce poflible to bring
^uch to our Examination ; but Water being
tranfparent, and confining the Creatures in it,

are able, by applying a Drop of it to our
glafles, to difcover (to a certain Degree of
,^inallnefs) all that it contains. My Attention
nas been therefore applied more particular-

ly to infped the Waters; in doing which I
have been kindly affifled by fome ingenious
Friends ; and the following Fiâtes and Sheets
exhibit the Figures and Defcriptions of fuch
of the minute Inhabitants thereof as have
fallen in my Way, and feemed to me the
moft curious and extraordinary. And as
Names are of the utmoft Service to make
People underftand one another, I hope to be
indulged the Liberty of giving fuch to thefe
hitherto unnoticed Animalcules, as corre-
fpond in fome Manner to their Appearances;
even though I may not always have chofen
the moft proper.

' I ''HE wonderful Animalcule I am going
j|[_ to defcribe, was I believe firft taken
Notice of by my curious Friend Mr. William
Arderon, of the City of Norwich, before
fpoken of in this Treatife, who kindly fent
me an Accour|t thereof, together with many
thoufands of the Creatures themfelves; which
came to me alive, in a Veffel of the fame
Water they were found in, and lived with
me feveral Weeks : whereby I had frequent
'Opportunities of being convinced how care-
fully he had obferved them, and likewife
Was enabled to relate many Particulars from
my own Knov/ledge.

This little Animal (the Form whereof may
be feen Plate-^X. Nquot; I.) is extremely flen-
der, and not uncommonly one hundred and
fifty times longer than broad. Its Refem-
blance to an Hair has induced us to call it
the Hair-like InfeSl. The Body, or Middle
Part, which is nearly ftrait, appears in fome
compofed of fuch parallel Rings as the
Windpipe of Land Animals confift of, but
feems in others fcaled, or rather made up of
Rings that obliquely crofs each other. This
Difference may be feen in the two Figures
F, G. Its two Ends are bent, or hooked,
pretty nearly in the fame Degree, but in a
Diredlion contrary to each other; and, as
no Eyes can be difcerned, 'tis difficult to
judge which is the Head or Tail.

Its progreflive Motion difi^ers from that of
all Animals befides hitherto defcribed, fof
notwithftanding the Body is compofed of
many Rings and Joints, it feems unable to
bend at all, or move direclly forwards : but
when it is inclinable to change its Quarters,
it can move from Right to Left, or Left to
Right, and proceed at the fame Time back-
wards or forwards obliquely. And this it
performs, by turning one End about, the
Quarter of a Circle, as the Arc a b ftiews ;
then it does the fame with the other End,
and fo alternately: whereby its Progreflion
is in a diagonal Line, or from Corner to
Corner; as whoever will take the Trouble

to fliift the Points of a Pair of Compalfes in
that Manner may immediately be fatisfied.

All its Motions are extremely flow, and
require much Patience and Attention in the
Obferver. It has neither Feet, nor Fins, nor
Hairs, but appears perfectly fmooth and
tranfparent, with the Head bending one
Way and the Tail another, fo as to be like a
long Italian f: nor is any internal Motion,
or particularly opake Part to be perceived,
which may determine one to fuppofe it the
Stomach or other of the Inteftines.

Thefe Creatures are fo fmall that Millions
of Millions might be contained in an Inch
Square. When viewed fingly, or feparated
from one another, they are exceedingly
tranfparent, and of a lovely green j but like
all other tranfparent Bodies, when Numbers
of them are brought together they become
opake, and lofe their green Colour, in pro-
portion as the Qiiantity increafes, till at lafl:
they appear intirely black.

They were firft difcovered in a Ditch at
^oruoichy one End whereof communicates
'^ith the River there, and the other End
with a fécond Ditch, into which- feveral
Kennels empty themfelves from diftereht
Parts of the City. The Length of this Ditch
at leaft an hundred Yards, and its Breadth
nine : the Bottom, for more than a Foot in
Depth, is covered with a blackifh green Sub-
ftance, in Appearance like a Mud, made up

wholly of thefe and other Infefls, intermix-
ed with différent Sediments from the Waters
He affures me, he has conftantly found much
the greater Part of this black Matter to be
really Infeéls : but were they only one half
or a quarter Part thereof, what Numbers
beyond all Conception muft, this Ditch con-
tain 1

It was Accident (whereto more Difcove-
ries have perhaps been owing than to Defign)
that fortunately prefented thefe Animalcules
to Obfervation.—My Friend having got
fome Water from this Ditch, with Intent to
examine by the Microfcope other Infects he
had taken Notice of therein, found before
his Eyes a great Abundance of flender Hair-
like Fibres, which he imagined to be the
Stems or Roots of fome extremely fmall
Water Plants, from their appearing to him
without any Life or Motion, tho' he won-
dered much at their Uniformity of Figure.
Being however not fatisfied with a Angle
View, but continuing them under the Mag-
nifier, and looking at them now and then,
he perceived that many of thofe feeming
Hairs which he had feen before feparated
from one another as at d, in N° II. were
flowly drawing themfelves together in Com-
panies as at e in the fame Number.—This
gave him the firft Notion of their being liv-
ing Creatures, and fet him upon watching
them fo narrowly, that he was quickly con-
vinced.

vlnced, not only of their having Life, but
iikewife of their being able to change their
Situation, either from Right to Left, or Left
to Right, backwards, or forwards, at Plea-
sure, in the Manner juft now defcribed.

Being thus far fatisiicd, he applied him-
felf very diligently to examine the Structure,
Motions, and other Properties of thefe mi-
nute Creatures; and found, by viewing
them feveral Times, and through different
Magnifiers, that altho' they are moft com-
monly compofed of little Ringlets, whofe
Joinings appear like parallel tranfverfe Lines
as at p', N* I. many however were feen
amongft them, in which great Numbers of
minute Rings feemed to crofs one another obr
liquefy, and reprefented Scales, {vid. NT. G.)
but whether thefe are different Species or
not muft ftill remain a Doubt.

After putting a large Spoonful of the be-
lorementioned black or rather dark green
thick Matter into a Glafs Jar, he filled it up
^ith Water, very gently, as high as h, Nquot;
Jfi. then leaving the faid Matter to fettle and
qiuetly at the Bottom of the Veft'el, its
nole Appearance prefently afterwards is
^newn in the fame Glafs at /.

nathad happened amongft thefe Myriads of
^ quot;le Animals, he found that a Multitude of
thpJ^r^'^' as it were by Agreement, placed
tiiemfelves on the Side of the Jar, and ap-
peared

peared marching upwards in Rows, after the
Manner reprefented Nquot; IV. /. and that fome
of them had travelled to the Diftarice of ■
three or four Inches, vgt;'hich confidering the
Slownefs of their Motion, and their Method
of moving forwards, muft be looked upon

In about two Days great Numbers had
travelled up the Side of the Jar, to above the
Surface of the Water, as at k N-.IV-: when
after being expofed to the Air for a little
while, their fine green Colour became chang-
ed into a moft beautiful Sky-blue.

This fine dark green Matter or Congeries
of Animalcules, is fo nearly equa;l to the
fpecific Gravity of Water, that at firft put-
ting in, it either floats at Top, or coqti,n.ues
at the Bottom, or in the Middle of the Jar,
juft as Accident has difpofed it. But if Part
of thofe that are fwimming at the Top of
the Water have an Inclination to go down-
wards, they form themfelves into a Sort of
Line or Rope, which defcends extremely
flow, till they arrive as low as they intend :
And they are able to fufpend themfelves in
the Water where they pleafe, and as long as
they have a Mind. ; Their Method of doing
this is fliewn N° V. f cf. Thofe however
who happen to be near the Side of the Jar
move themfelves down thereon, and that
commonly in a winding fcrew-like Manner,
as « « N° V. is intended to reprefent.—Their

A fmall Quantity of this Matter having
one Day been put into a Jar of Water, it fo
happened that one Part thereof went down
immediately to the Bottom, whilft the other
Part continued floating upon the Top. ^H
Things remained a good while in this Con-
dition, until at laft each of thefe Swarms of
Animalcules grew weary of its Situation, and
had a Mind to change its Quarters. Both
Armies, in ftiort, began their March at the
fame Time againft the Side of the Jar j and
as one proceeded upwards, and the other
downwards, after fome Hours, they were
near meeting about the Mid-Way j as the
Route each of them appeared to take, foon
after they began to move, made it very eafy
to forefee they would. The Deflre of know-
ing in what Manner they would behave on
this Occafion, engaged the Obferver to watch
them with a careful Eye, and as they ap-
proached ftill nearer, he beheld, to his great
Surprize, the Army that was marching^ up-
^vards, open to the l^ht and Left, and leave
a convenient Space for the Army that was
marching downwards to pafs between its
Wings. Thus without Confufion or Inter-
mixture each held on its Way: the Army
mat was going upwards marching in two
Columns to the Top, and the other pro-
ceeding with great Regularity and Order in

S40 Of the Hair-like InfeSt.
one Column to the Bottom. Nquot; VI. Is a Re-
prefentation of this amufmg Accident, which
ferves to fhew, that however mean or con-
temptible thefe Creatures may appear to us_,
the Power that created them has not left
them deflitute of Sagacity, to affociate toge-
ther, and adt unanimoufly for the Benefit of
the Community ; both thefe Armies march-
ing as regularly as if under the Diredion of

When thefe Animalcules are taken from
the Ditch, and any other Water poured up-
on them, it is difficult to make them live
twenty-four Hours j but when kept in fome
of the fame Ditch-Water, they may be pre-
ferved in good Condition for feveral Months.
Though they never are fo vigorous, nor fliew
their Way of moving from Place to Place fo
plainly, as when newly taken up.—Their
Kind of Motion, as before defcribed, makes
it evident, that if they move along the Side
of a cylindrical Glafs Jar, either upwards or
downwards, it mufl; be in a Spiral Line; and
fuch it is always found to be.

It is not yet difcovered whether their Food
he Infeds exceflively minute, or Particles of
Matter floating in the Water j neither do we
know any thing concerning the Manner of
their being propagated. They have as yet
been taken Notice of only in this Ditch, but
'tis reafonable to believe that other Places of

the like Kind, will, upon Examination, be
found to produce them alfo, and even in
great Abundance.

IN the fame Ditch-water from Norwich
came likewife great Numbers of the
little Creatures, .whofe feveral Appearances,
when examined by the Microfcope, are
fliewn Flate X. N° vii.

My curious Friend pointed it out to my
Obfervation by the Name of the Oat-Ani-
mal-, and as, at firll: View, it much refem-
bies a Grain of that Sort, I flaall here de-
fcribe it under the fame Name..

This Creature is fo very fmall, that no
true Judgment can be made of it, unlefs
it be looked at through the greatefi Mao--
'^ifier, nor even then without confiderable
Attention. I commonly found two or three
them in a Drop of the Sediment, amongft
Multitudes of the Hair-like Infedl, lying
the Bottom of the Water wherewith the
Same Sediment was diluted, upon the Plate
Glafs, without any vifible Motion or
Appearance of Life : being inclofed in a
S^ivalve-fhell, which the Animal can open
or fhut as it is inclined ; but which it
n.nbsp;Rnbsp;con-

conftantly ftiuts upon being difturbcd, nor
opens again until after having been quiet for
fome Time. Its Appearance when ftiut is

The Shell is fo exquifitely thin, and con-
fequently fo very tranfparent, as to be tra-
ced out, when fliut, only by a faint Line
on the Back, where the Cardo or Hinge
makes fome additional Thicknefs ; but when
open, the Edges of both its Sides may be
diftinguiftied plainly. The two Ends of
the Shell can open, whilft the middle Part
remains clofed, and in that Condition it is
like the Pholas and' fome Species of the
Chama-, but differs from them, in-being
able to ftiut both Ends and alter the Fi-
gure of its Shell, which they cannot do.
This probably is performed by Means of
certain Articulations in the Shell, near Jts
Extremities, which are too fine to be dif-
cerned. When thefe Ends are open, the
Creature frequently thrufts out, at each, a
cylindrical fleftiy Part, (as zt Jig. 2.) which
may be fuppofed the Head and Tail ; but
their Minutenefs renders it hardly poftible
to difcover any Difference between them-
In this Pofture it is probable the Creature
feeds, on that Provifion the Water bring® '
though it depends not wholly on fuch AC'
cident, for it can change its Place by Jerks,
or Leaps, which it makes by the AftioiJ
of fome ftrong Mufcles in the two protruded
^nbsp;Parts,

Parts, whofe Spring throws it to the Diftance
at leaft of its own Shell's Length every Time
tjiey are exerted. Thefe Leaps however
have long Intervals between, and are never
inade till the Animal is perfedly undif-
turbed.nbsp;^ gt;

Both the Shell and Body are ufually fo
tranfparent, that when the Shell is clofed
nothing can be perceived but a Sort of Shade
within it: but, now and then, I have feen
Iht Body, plainly, through the Shell, in
ohape as at/^. 3.

Several of them have a Couple of very
dark round Spots, one whereof is feem-
ingly placed within each Side the Shell,
as in fg. 4. Thefe I imagined to be
compad Ligaments, ferving to open and
fhut the Shell, and correfpondent to thofe
that Oyfters, Mufcles,. Scallops, amp;c. are
furnifhed with for the like Purpofe. But
when I obferved others of them, having
three, four, or five of the fame round Spotst
i began to think myfelf miftaken ; and
inould rather fuppofe them concreted Bo-
dies fimilar to the Pearls bred in feveral
^inds of Shell-fifti, did not the Regularity
pt their Pofition render this likewife a little
improbable.

One, having five Spots, with its Shell
gaping the whole Length, and both Ends
thereof fully extended in a ftrait Line,
very different from what precede, is ex-

hibited Jig. 5.— In this Condition, which
is not uncommon, it much refembles a Grain
of Oats.

I muft not omit to mention another
Variety amongft thefe Creatures, which the
fig' 7'nbsp;^^^ intended to explain.

Here we fee a Couple of tranfverfe Lines,
forming a Kind of Zone acrofs the Middle
Part of the Shell, and feeming to feparate
the two Ends thereof.

'Tis difficult to determine whether thefe
are another Species, or only fome of the
fame Sort of Animals in a different State
or Condition. I much fufpeft they may
be about cafting their Shells, or perhaps
diftempered, or even dead; for I have never
feen any of them open their Shells, or make
the leaft Motion, though I have fometimes
kept my Eye over them for above a Quarter
of an Hour.

TH E Anguillce, or little Eel-like Aniquot;
malcules, which are frequently fo nu-
merous m four Pajle that the whole Surface

of it appears alive, and are feemingly of the
fame Kind with thofe fometimes found in
Vinegar, were fome of the firft minute
Creatures the Microfcope was made ufe of
to examine, and are ftill the moft com-
mon living Objeds it is employed about;
I ftiould not therefore, after their having
been fo long known, and fo often defcrib-
ed, have introduced them here, had not a
very pretty Difcovery made a few Years
ago, by Mr. James Sherwood, an ingenious
young Surgeon, rendered them the Sub-
Jed of a curious and entertaining Experi-
ment.nbsp;^ ^

Separating one of thefe fmall Eels from
a Number of others, in order to examine
it by the Microfcope, and wounding it
accidentally in the Belly, he took Notice
that a long flender Tube, doubled like an
Inteftine, proceeded from the Wound:
of which informing Mr. Needham, it ex-
cited their Curiofity to cut in two another
t^el, near its Middle : when they difcover-
ed a Number of living young ones, each
inclofed in its proper Membrane, ifliiing
Jj-om what now plainly ftiewed itfelf to be
Uterus. This induced him to make
farther Trials, and finding ufually the fame
Appearance, he thought proper to commu-
liicate his Qbfervations to his Friends, and
^-terwards to the Royal Society

I firft faw the Experiment with Mr.
Sherwood, and having fince made it Abun-
dance of Times myfelf, am qualified to
dired thofe who may defire to be fatif-
fied, how to perform it themfelves, with-
out any great Difficulty. — Having taken
up a very fmall Quantity of the Pajle
where thefe Eels abound, on the Point of
a Pin, or with a fharpened C^ill, lay it
on a Slip of Glafs and diluting it well
with Water, many of them will become
vifible to the naked Eye : then with the
Nib of a Pen cut to a very fine Point, and
ftiaved fo thin as to be extremely pliable,
fingle out one of the largeft Eels, and in-
fmuating the Point of the Pen underneath
it, remove it into a very fmall Drop of
Water, which you muft have ready pre-
pared on another Slip of Glafs. When
thus confined, it may eafily be cut afun-
der, tranfverfely, by the Help of a good
Eye and fteady Hand, with a Lancet or '
fliarp Penknife ; or if the Eye is deficient,
a Hand-Magnifier will enable almoft any
body to perform the Operation. As foon
as the Parts are feparated, apply your Ob-
jedt to the Microfcope, and if the Divifion
has been made about the Middle of the
Animal, feveral oval Bodies of different
Sizes will be feen to iflTue forth. Thefe
are young Anguillce, of different Degrees
of Maturity, each whereof is coiled up and

included in its proper Membrane, which
IS of fo exquilite a Finenefs as to be fcarce
difcernable by the greateft Magnifier, while
It inclofes the Embrio Animal. The largeft
^oftforward break immediately through
this delicate Integument, unfold themfelves,
and wriggle about in the Water nimbly :
others get out, uncoil, and move about
more flowly; and the leaft mature con-
t'nue intirely without Motion. The U-
terus, or Vefl'el that contains all thefe
oval Bodies, is compofed of many Annuls
or Rmglets, not unlike the Afpera Arteria
of Land Animals, and it feems to be con-
siderably elaftic ; for as foon as the Opera-
tion is performed, the oval Bodies are thruft
out with fome Degree of Violence by the
fpringing back or Aftion of this Bowel.
An hundred and upwards of the young
ones have been feen to iflhe from one
fingle Eel, whereby the prodigious Increafe
of them may be accounted for ; as pro-
bably feveral fuch numerous Generations
^re produced in a ftiort Time. Hereby
^ve alfo learn that thefe Creatures are not
only hke Eels in Shape, but are likewife
tTtf^'^^^^ as Eels are generally fuppofed

I fcarce know a more entertaining Ex-
periment ; and you'll very feldom be dif-
appointed, for they feem like Earth-worms
10 be all prolific, and unlefs by Accident

you cut one that has brought forth all its
Young before, or make your Trials when
the Pafte has been kept a very long Time,
(in which Cafe I have found them fome-
times unfruitful,) you'll not fail of being
diverted after the Manner above defcribed.

One of the Anguillce, greatly magnified,
and through the Body of which, before
cutting, faint Traces of the young ones
may be difcerned, is fliewn, Nquot; VIII.
Plate X.

The fime, after being cut, with young
ones iffuing from it, and the Uterus as it
ufually appears, is reprefented in a Drop of
Water, N° IX.

This Difcovery is of more Confequence
than without due Confideration it may feem
to be ; for as thefe Animalcules are plain-
ly viviparous, and bring forth living and
ferfeSl young ones in their Eel-like Form,
it is highly improbable that they ever be-
come Flies, or undergo any other Change \
fince no Animal has been yet known to
put on a new Shape after it has produced
its Young, whether in the Egg or other-
wife. Therefore if thefe Ajiguillce never
change to Flies, or lay Eggs, which this
Experiment renders it very unlikely they
fhould ever do, they can neither convey
themfelves to any Difi:ance from the Pajk
wherein they firft appear, nor be propa-
gated by Eggs floating in the Air. The

Queftion then will be, by what Means they
get into the Pajle^^t all: for fuppofing it
polTible they might have been in the Wheat,
and have efcaped unhurt through the feveral
Operations of grinding the Corn, fifting it,
it is fcarcely credible (in whatever Con-
dition they might remain in the Flour) that
they Ihould be able to endure boiling, with-
out which, and that too for a confiderable
Time, no good Fajie can be made.

For my own Part, I muft acknowledge,
that before this Difcovery I was ftrongly of
Opinion that thefe Eels change into Flies ;
as many Kinds of Worms found in Waters
are well knov/n to do, and in that State de-
pofit their Eggs in whatever Places they find
a proper Neft and Provifion for their future
Offspring ; and this my Opinion I thought
confirmed, by fometimes obferving very mi-
nute Flies, of a Size agreeable to fuch a Sup-
pofition, hovering about the Glaffes where
Pajle'wiih. Eels was kept. But as bringing
forth living young ones, in their Eel-like
State, is a Fad: beyond all Doubt, I muft
believe the Flies I faw about the Pajie are
Infefts of fome other Kind, and have no
Relation to thefe Eels; unlefs we could
imagine them to have a two-fold Method of
Generation ; that is, to be both viviparous
^nd oviparous, and to propagate both in the
JEel and in the Fly State j which is too ex-
traordinary

Thefe Difliculties muft be left to future
Enquiry ; and I hope the Curious will en-
deavour to folve them by careful Experi-
ments and Obfervations.

IHE Difcovery of a certain Kind of
_ Anguillce, or Animalcules refembling
Eels, in blighted Wheat, was made acciden-
tally by my very ingenious Friend Mr. Tur~
berville Needham, in the Summer of the Year
1743, in the Manner defcribed by himfelf
in his curious Book, of New Microfcopical
Difcoveries -f*.

Thefe Animalcules are not ufually lodg-
ed in fuch blighted Grains of Wheat as are
covered externally with a Soot-like Dull,

• Mentzelius publilhed Obfervations made on the Procefs
of the Transformation of Eels in Vinegar, which, he tells the
World, he faw iffue in Flies ; which Flies did afterwards lay
their Eggs in the Vinegar, ijc. And he has given Drawing»
cf the faid Flies with his own Hands. On the contrary,
D. Marcus Antonius Cellius affirmed to the Phyfico-mathema-
tical Society at Rome, Anno 1688, that with very good
Microfcopes of his own making he found the Eels in Vinegar
to be 'viviparous.
t Vid. iViw Microfcopical Difcoveries by Mr. Needham, p- 85-

(whofe Infide is likewife frequently con-
verted into a black Powder :) but Abundance
of Ears may be obferved in fome Fields of
Corn, having Grains that appear blackifh, as
if fcorched; and fuch when opened are found
to contain a foft white Subjiance, that atten-
tively examined feems to be nothing elfe
but a Congeries of Threads, or Fibres, lying
as clofe as poffible to each other in a paral-
lel Diredlion, and much refembling the un-
ripe Down of fome Thirties, on cutting open
the Flower-Heads before they begin to blow.
This fibrous Matter difcovers not the leaft
Sign of Life or Motion unlefs Water be ap-
plied to it ; but immediately on wetting
(provided the Grains of Wheat are newly
gathered) the fuppofed Fibres feparate, and
prove themfelves to be living Creatures, by
Motions that at firft are very languid, but
gradually become more vigorous, twifting or
Wriggling themfelves fomewhat in the Man-
ner of the Eels in Pafte, but always much
flower than they, and with a great deal lefs
Regularity ; for in them the Head and Tail
are conftantly moving, contrarywife, and
alternately, with the fame Kind of bending
or Undulation in the Bodies of them all j
whereas the Animalcules we are now de-
fcribing have no Uniformity in their Motion,
but bend their two Extremities fometimes
diff^erently, and fometimes in the fame Di-
redion.

If the Grains of Wheat are grown dry by
keeping, and you cut them open in that
Condition, the fibrous Matter is very diftin-
guifhable, and on putting Water to it will
feparate with great Readinefs, and feem like
fine Tubes or Threads tapering at both
Ends: but not the leaft Motion or Symptom
of Life will be perceived till they have been
in Water for feveral Hours; nay, frequently
they will never revive or come to move at
all. But if the fame Grains be fteeped in
Water for fome Hours, or buried for three
or four Days in Earth, till they are fully
ikttirated with Moifture, and then opened
with a Penknife, on taking out a fmall Por-
tion of the White Matter carefully, and
fpreading it thin upon a Slip of Glafs, the
Animalcules may be feen bundled together,
2nd extended longitudinally, but without
Motion; and though upon the Application of
Water, they will not revive fo loon as thofe
taken from frefh Grains, whofe Moifture
has never been exhaled; yet, after abiding
an Hour or two in Water, I have conftantly
found them alive and vigorous; and that,
potwithftanding the Grains have been kept
in a dry Condition even for fome Years; of
which I have a remarkable Inftance now hc^
fore me.

In the Month of Auguji 1743, a fmall
Parcel of blighted Wheat was fent by Mr.
Needham to Martin Folkes, Efq; Prefident of

the quot;Royal Society, (with an Account of his
then new Difcovery :) which J^arcel the
Prefident was pleafed to give me, defiring
I would examine it carefully. In order fo
to do, I cut open Ibme of the Grains that
were become dry, took out the fibrous Mat-
ter, and applied Water to it on a Slip of
Glafs J but could difcern no other Motion
than a Separation of the Fibres or Threads;
which Separation I imputed wholly to an
Elafticity in the Fibres ; and perceiving no
Token of Life, after watching them with
due Care, and repeating the Experiment
till I was weary, an Account thereof was
written to Mr. Needham; who having by
Trials of his own found out the Caufe of
this bad Succefs, advifed me to fteep the
Grains before I fhould attempt to open them;
on doing which I was very foon convinced
of his Veracity, and entertained with the
pleafing Sight of this wonderful Phcenome-
non. Since then I have made Experiments
at different Times with Grains of the fame
Parcel, without being difappointed fo much
as once, and particularly on the fourth Day
July 1747» finding fome of the fame Par-
cel left, I foaked a Couple of Grains in W^ater
for the Space of thirty-fix Hours, when be-
lieving them fufficiently moifl:ened, I cut
one open, and applying fome of the fibrous
Subflance to the Microfcope in a Drop of
Water, it feparated immediately, and pre-

fen ted to my View Multitudes of the An-
guillce, lying as reprefented N° X. B, with-
out the leaft Motion or Sign of Life. But
Experience having taught me by former
Trials, that they might notwithftanding
poftlbly revive, I left them for about four
Hours, and then examining them again,
found much the greateft Number moving
their Extremities pretty brilkly, and in an
Hour or two after, they appeared as lively
as thefe Creatures ufually are. Mr. Folkes
and fome other Friends were Witneffes of
this Experiment.

We find an Inftance here, that Life may
be fufpended and feemingly deftroyed; that
by an Exhalation of the Fluids neceffary to
a living Animal, the Circulations may ceafe,
all the Organs and Veffels of the Body may
be ftirunk up, dried, and hardened; and yet,
after a long while, Life may begin a-new to
adtuate the fame Body ; and all the animal
Motions and Faculties may be reftored,
merely by replenifliing the Organs and Vef-
fels with a frefti Supply of Fluid. Here is,
I fay, a Proof, that the Animalcules in the
Grains of blighted Wheat can endure hav-
ing their Bodies quite dried up for the Space
of four Years together, without being there-
by deprived of their living Power : and
fince, after they are become thus perfedly
dry and hard, there feems little Room for
farther Alteration, unlefs their Organs ftiould

be broken or torn afunder; may they not
poffibly be reftored to Life again,- by the
fame Means, even after twenty, forty, an
hundred, or any other Number of Years,
provided their Organs are preferved intire ?
This Queftion future Experiments alone can
anfwer.

Some late Difcoveries ferve to Ihew our
Ignorance concerning the real ElTence and
Properties of what we term Life; and, if
modeflly confidered, may contribute fome-
what towards improving and enlarging our
Ideas of it. Thefe Anguillae, the Wheel Ani-
mal, and I doubt not many other Kinds
hitherto unobferved, are able to inftrud; us,
that Lfe, or, the living Power, may be fuf-
pended or ceafe to a£t for a Length of Time,
and yet afterwards may be reftored to its
former Vigour. The cutting of the Polype
and Star-Fijh into Pieces, the Continuance
of Life in thofe Pieces, and their reproduc-
ing all the Parts neceflary to make each of
them a perfed Polype or Star-Fijh, prove
beyond all Contradiftion, I will not fay that
Lifeiiklf maybe divided, (left I ftiould give
Offence,) but that an Animal pofejfed of Life
may be cut afunder, and the Parts thereof
live afterwards, quite feparate from and ab-
folutely independent of one another; that all
the Members wanting to, each Part may be
reproduced; that, in Time, each Part may
become as large an Animal, and as perfect

to all Appearance, as that of which it waS
no more than a maimed and imperfedl
Part *and befides all this, that they may
multiply, and produce young ones, in as
great Numbers, and after the fame Manner,
as thofe of that Kind that were never cut.—
Thefe are Truths, the Belief whereof would '
have been looked upon fome Years ago as
©nly fit for Bedlam.

What Life really is, feems as much too
fubtile for our Underft:anding to conceive of
define, as for our Senfes to difcern and ex-
amine.' We have, I think, no Criterion or
fenfible Proof whereby to diftinguifh Life^
but Motion; and there certainly are Motions
fo extremely languid, that they can neither
become the Objeft of our Eyes or our
Ideas ; therefore were Motion infeparable
from Life, (which is a Point we cannot I
think determine) both might poflibly exift
in many Bodies where we fuppofe them
not. But whatever be the Ejence of Life,
it is perhaps not to be defiiroyed, or really
injured, by any Accidents that may befall
the Organs wherein it adls, or the.^o^'
inhabits. Dv. Butler, the late Bifhop of Dur-
ham, in his ingenious Analogy of Religion to
the Confiitution and Courfe of Nature, gives it
as his Opinion, page 21, that quot; We have no

with living Powers, ever lofes them du-
quot; ring its whole Exiftence, than to believe
quot; that a Stone ever acquires them.quot;—quot; The
quot; Capacity of exercifmg them for the pre-
'' fent, as well as the adlual Exercife of
quot; them, may be fufpended, (fays he, page
quot; 22.) and yet the Powers themfelves re-
quot; main undeftroyed.quot;

But leaving a Subjedl of which we
know fo little, to fpeak fomething farther
of our Anguillce:—It appears plainly from
the foregoing Experiments, that when the
blighted Grains of Wheat have been kept
a long Time, and the Bodies of thefe Ani-
malcules are confequently become extreme-
ly dry, the Rigidity of their minute Vef-
fels requires to be relaxed very gently,
and by exceeding flow Degrees; for we
find, that on the Application of Water
immediately to the Bodies of thefe Ani-
tnalcules when taken from the dry Grains,
they do not fo certainlv revive, as they do
n the Grains themfelves be either buried
jn Earth or fteeped in Water for fome
Time before they are taken out. The Rea-
son of which moft probably is, that too
fudden a Relaxation burfts their delicate
and tender Organs, and thereby renders
them incapable of being any more em-
ployed to perform the Anions of Life.
And indeed there are always fome dead

ones amongft the living, whofe Bodies ap'»
pear burften or lacerated, as well as others
that lie extended (in the Manner fhewn be-
fore Nquot; X. B.) and never come to Life,-
though we can't difcover any fenfible Injury
they have received-.

Some Difcretion is needful,» to adapt the
Time of continuing the Grains in Water
or Earth to the Age and Drynefe of them 5
for if they are not opened before they have
been too much or to long foftened, the-
Animalcules will not only feem dead, but
will really be fo. Of the two- Grains I
mentioned to have been four Years old when
put to foak, I opened one after it had lain
thirty-fix Hours, and the Event was as al-
ready related: the other I let lie for above
a Week, and on opening found all the^^w-
cuilla near the Hufk dead, and feemingly
in a decayed Condition; but great Num-
bers iffued alive from the Middle, and

Hulks are opened to let thefe Creatures
out after they have been fteeped, they all
inevitably perifh in them; and when take»
•out and preferved in Water, if the Hufks
are left with them, they will die in a fe^^^
Days; but otherwife they will continue
alive in Water for feveral Months together^
and ftiould the Water dry away, may d^
revived again by giving them a frefh Sup-

, Since the Animalcules we find in blighted
Wheat, as well as thofe in four PaJie, are
of an Eel-like Figure, it might be very
eafy (by fuppofing them both the fame)
to form plaufible Conjectures concerning
the Produdlion of Eels in Pajie, a Particular
which at prefent feems fo difficult to be ac-
counted for: But as Truth ought to be the
only Objedl of our Enquiries, I think myfelf
obliged to fhew wherein they differ, left
others, who maynot have the Opportunities,
or take the fame Pains to examine ■ them,
fhould pofiibly be milled into fuch Mifi:akes
by their being fomewhat alike.

It is evident at firfl Sight, on their be-
ing viewed and compared together, that
the Angttillet of blighted Wl^eat are in gene-
ral longer and a great Deal flenderer than
thofe in Pajie, that their Motions are alfo
much flower, lefs vigorous, and more di-
verfified : not inceffantly wriggling the
Head and Tail, as the Pajie-Atiguillce do,
but lying fometimes motionlefs, and coiling
themfelves at other Times, more in the
Manner of Serpents than Eels. They are
alio more tranfparent, and efpecially for
fome Length from the two Extremities:
Put the moft diflinguifhing Mark of all,
is a very clear Part about the Middle of
their Bodies, which approaches to an
oval Figure when viewed in fome Direc-
tions, tho' it more frequently appears • tri-
S 2nbsp;angular.

A B fPlate X. N° X.) reprefent a Couple
©f thefe Anguillce. The Figure B {hews
how they lie extended, when they firft
are taken out from the Grain, and feparate
in a Drop of Water, either before they
begin to move, or when they are really
dead.

A reprefents one of them alive and vigo-
rous, and endeavours to fhew the Manner
of its moving. The tranfparent triangular
Spot is pointed out in both o o.

N' ONE, of the many different Animal-
cules I have yet examined by the
Microfcope, has ever afforded me Half the.
Pleafure, Perplexity, and Surprize, as that
I am going to defcribe at prefent: whofe
Ability of afiTuming different Shapes, and
thofe fo little refembling one another, that
nobody (without aftually feeing its Tranf-
formation performed under the Eye) would
believe it to be the fame Creature, has given
me Reafon to diftinguifti it by the Name of

getables have been infufed, or Animals pre-
ferved, has flood quietly, for fome Days or
Weeks, in any Glafs, or other Velfel, a
flimy Subftance will be colledled about the
Sides; fome whereof being taken up with
the Point of a Penknife, placed on a Slip
of Glafs, in a Drop of Water, and looked
at through the Microfcope, will be found
to harbour feveral Kinds of little Animals,
that are feldom feen fwimming about at
large. The Infed we are treating of is one
of thefe j and was difcovered in fuch Slime-
like Matter, taken from the Side of a Glafs
Jar, in which fmall Fifhes, Water-fnails,
and other Creatures had been kept alive
two or three Months, by giving them frefh
Water frequently; though the Sides of
the Jar had feldom or never been wiped or
cleaned.

Having one Evening been examining a
little of this Slime, which I found plenti-
fully flocked with feveral Kinds and Sizes
of Animalcules that were to me no Stran-
gers, fuch as Bell-Animals, Wheel-Animals,
Funnel-Animals, and others whereto as
yet no N.imes are given; I was diverted
quot;with the fudden Appearance of a little Crea-
ture whofe Figure was intirely new to me,
Ploying about with great Agility, and hav-
ing fo much feeming Intention in all its
Motions, that my Eyes were immediately
fixed upon it with Admiration. Its Body

in Subftance and Colour refemhled a Snail's j
the Shape thereof was fomewhat elliptical,
but pointed at one End, whilft from the
other a long, flender, and finely propor-
tioned Neck ftretched itfelf out, and was
terminated with what I judged to be an.
Head, of a Size perfedly fuitabie to the
other Parts of the Animal. In ihort, with-
out the leaft Fancy, which is ever care»
fully to be guarded againft in the Ufe of the
Microfcope, the Head and Neck, and indeed
the whole Appearance of the Animal, had
no little Refemblance to that of a Swan;
with this Difference however, that its Neck
was never raifed above the Water, as the
Neck of a Swan is, but extended forwards,
or moved from Side to Side, either upon the
Surface of the Water, or in a Plane nearly
parallel to the Surface thereof.
■ Nquot; XI. Plate X. i. is an exaft Reprefen-
tation of this extraordinary Animal the firft
Time I ever faw it.

Its Size was about equal to that of the
Wheel-Animaly whofe general Form may
be diftinguiflied well enough by the fourth
Glafs of Mr. Cufs Microfcope, though the
firft is neceflary to form a Judgment ot
'its feveral Parts. It fwam to and fro with
great Vivacity, but flopped now and then
for a Minute or two, during which Time
its long Neck was ufually employed, as far

Side, with a fomewhat flow but eqtjable
Motion, like that of a Snake, frequently
extending thrice the Length of its Body,
and feemingly in Search of Food, Fig. 2.
attempts to fhew it as thus defcribed, but
is unable to exprefs the curious Turn and
Elegance of its Shape.

I could difcern no Eyes, nor any Opening
like a Mouth in what appears to be the Head;
but its Actions plainly prove it an Animal
that can fee; for notwithftanding Multi^
tudes of different Animalcules were fwim-
ming about in the fame Water, and its own
progreffive Motion was very fwift, it never
flruck againfl any of them, but direded its
Courfe between them, with a Dexterity
wholly unaccountable, fhould we fuppofe it
deflitute of Sight.

This Creature feemed to me fo extraor-
dinary, I could not forbear calling all my Fa-
mily to fee it. And after having viewed it
by the fourth Magnifier, that being the Glafs
i was uflng when I firft difcovered it, we
were very deflrous to examine it more ftridt-
ly by enlarging it ftill more. Being there-
fore obliged to ftiift the Glafs, which took up
fome little Time, I loft my Animal as unac-
countably as I had found it; all the Search i
could make, for Half an Hour at leaft, being
unable to difcover any Thing bearing the leaft
Pvefemblance to it : tho' I replaced,the Glafs
i liad employed before, and carefully travel-
S 4nbsp;led

led over the vi^hole Drop a great Numbef
of Times. All 1 found remarkable there'
in, but which I regarded very little, was
a pretty large Animalcule, that I remem-
bered to have feen before what I was
now feeking for had prefented itfelf to View,
and whofe Appearance was as at fig. 3.
In a Word, after much Pains to no Man-
ner of Purpofe, concluding my new Ac-
quaintance irrecoverably loft, though I could
not conceive how, I put the Microfcope
afide, very much difappointed and diffa-
tisfied.

A Fortnight or three Weeks after, exa-
mining fome more of the fame flimy Mat-
ter, I was again furprized and pleafed with
another of thefe Animals, that ftarted up
under my Eye, and fwam about as the for-
mer had done : but the Water it was in be-
ginning to dry away, and being employed a
few Moments in adding a frefh Supply, I
loft it as ftrangely as I had done before, and
looked for it again to as little Purpofe, till my
Patience was wearied out.

Frequently, after this, I examined the
fame Matter, in Hopes of finding fome of
thefe little Creatures, but all my Endeavours
proved fruitlefs j and therefore, as I could
give no better Account of them, I determin-
ed not to mention them at all. But one
Night, ftiewing fome other Animalcules in
the before-mentioned Slime, to my ingeni-
9nbsp;ous

cus Friend Mr. Turberville Needham, (whofe
long Acquaintance with the Microfcope has
made him equal at leaft to any body in the
Knowledge and Ufe thereof,) we fortunately
and iinexpedledly difcovered one of thefe, and
refolved to watch it carefully by Turns, and
fatisfy ourfelves concerning it as far as pof-
fible. Nor indeed were our Precautions need-
lefs; for when it had been fwimming about
a confiderable While (in the Pofi:ures repre-
fented by fg. I and 2.) we beheld it on
a Sudden draw in its Neck and Head in the
Manner that a Snail does, fo that both of
them difappeared intirely : its Body became
then more opake, was fhaped ^sfg. 3. and
moved about very flowly with the large End
foremoft.

I was now fufficiently convinced how I
had been before deceived by the Animal's
difappearing in one Shape, and appearing in
another fo extremely different. The Dif-
covery we had made rendered us more ea-
ger to difcover farther, and determined us
not to leave it till it fliould re-affume its for-
mer Shape. But we were ftill more fur-
prized, v/hen, inflead of fo doing, we faw a
Kind of Head (though quite unlike what it
had before) thrufting itfelf out a little Way j
which new Head foon appeared furniflied
with a Wheel-like Piece of Machinery, the
quick Pvlotions whereof drew a Current of
Water to it from a confiderable Diftance.
The Animal in this Pofture is fhewn fig. 4.

Having often pulled in and thruftout thi$
fhort Head, fometimes with and fometimes
without the Wheel-work, the Creature, as if
weary, remained motionlefs for a While, and
then very flowly protruded its long Neck un-
der its own Body, as at fg. 5 ; foon after
which it fwam backwards and forwards ex-
tending its Neck, and turning it about every
Way with wonderful Agility, as if in Search
of Prey. Twice or thrice it altered the Form
of its Body, and difpofed its long Neck in
the Manner offg. 6.

Being now without Fear of lofing our Ob-
Jedt, we changed our Glaffes feveral Times,
and continued our Qbfervations till we were
fully fatisfied of its Transformation; and the
Figures herewith given were taken by my
Son (who has been much ufed to make
Drawings from the Microfcope) during this
Examination.

TPIE Royal Society having been pleafed
to accept very favourably a Defcription
cf this little Creature, addrefled to Martin
Folkes, Efq; their worthy Prefident; as I find
Bo Reafon fmce that Time for altering any
Part thereof, I fliaH give it here in the fame
Form and Words;

I Take the Liberty to lay before you the
beft Account my Obfervations can at
prefent furnifti out, concerning that w^on-
derful Water Infeft the Wheel /Inimal, which
you and feveral other of my curious Friends
belonging to the Royal Society have oiten
done me the Honour to examine by my
Glalfes, and admire along with me : and as
it is extremely difficult to convey by Words
only any true Idea of a Creature fo very ex-
traordinary, I have added exadl Drawings
of its different Forms, Poftures, and Ap-
pearances ; in Hope, by that Means, of be-
ing underflood by thofe who have never
feen the Subject, as well as approved of by
thofe that have: in cafe you ftiall judge thefe
Lines worthy to appear where you prefide.

This wonderful little Infett is found in
Rain Water, that has ftood fome^ Days in
Leaden Gutters, or in Hollows of Lead on
the Tops of Houfes, or in the Slime or Se-
diment

diment left by fuch Rain Water; and if care-
fully fought after may be found alfo in
other Places. Mr. Leeuwenhoek, that diligent
Searcher into Nature, was the firft Difco-
verer of it about fifty Years ago (viz. in the
Year 1702) foon after which he communi-
cated an Account and Drawing thereof to
the Royal Society: both which may be feen in
•the^ 295th Num. of the Fhilofophical Tranf-
aSiions. What Regard was then paid^to his
curious Difcovery I am wholly ignorant, but
probably it was looked upon as a Matter of
great Difficulty to find the Animal, and for
that Reafon little or no Enquiry was made
after it, by the few who then amufed them-
felves with. Microfcopes: however, from that
Time till within thefe few Years (that Peo-
ple have begun to think the Works of their
Creator, however minute, not unworthy of
their Notice) I queftion very much whether
it has ever been feen by any one in England.

In order, therefore, to gratify the laudable
Curiofty which at prefent diff'ufes itfelf
amongft us, and feems the happy Omen of
great Improvements in the Knowledge of
Nature, I have not only (hewn this amazing
Animal to Numbers of Gentlemen at my
own Home, but having, by the Affiftance of
a more convenient Microfcope for the Pur-
pofe than Mr. Leeuwenhoek probably was
JVlafter of, examined it with the ftridleft

Attention, under all its various Appearan-
ces, and made feveral Qbfervations thereon
more than he has left us, the fame Motive in-
duces me to give the bell Account thereof I
can.

I call it a Water Aftimal, becaufe its Ap-
pearance as a living Creature is only in that
Element. I give it alfo for Diftindlion Sake
the Name of Wheeler, Wheel InfeSl or Animal;
from its being furnifhed with a Pair of In-
ftruments, which in Figure and Motion ap-
pear much to refemble Wheels. It can, how-
ever, continue many Months out of Water,
and dry as Duft; in which Condition its
Shape is globular, its Bignefs exceeds not
a Grain of Sand, and no Signs of Life appear.
Notwithftanding, being put into Water, in the
Space of Half an Hour a languid Motion be-
gins, the Globule turns itfelf about, length-
ens by flow Degrees, becomes in the Form of
a lively Maggot, and moft commonly in a few
Minutes afterwards puts out its Wheels, and
fwims vigoroufly through the Water in
Search of Food ; or elfe, fixing by its Tail,
yorks them in fuch a Manner as to bring
Its Food to it. But fometimes it will remain
a long While in the Maggot Form, and not

If the Water ftanding in Gutters of Lead,
or the flimy Sediment it leaves behind, has
any Thing of a red Colour, one may be almoft

certain of finding them therein and, if
in Summer, when all the Water is dried
away, and nothing but Duft remains, that
Du ft appears red, or of a dark brown, one
ihall feldom failj on putting it into Water, to
difcover Multitudes of minute reddifti Glo-
bules* which are indeed the Animals, and
will foon change their Appearance, in the
Maftner juft now mentioned.

The Minutenefs of thefe Animals makes
it almoft impofilble to know whether yoii
have them in the Water or not, without ex-
amining it by Glafifes : the fame Minutenefô
renders it alfo impraâicable to feparate therri
from the Dirt or Slime found along with
them, and on which perhaps they feed : in
fhort* they are intirely microfcopical InfeSis,

. and whatever is faid concerning them muft
be underftood to imply, as under Infpeâion
by the firft or fécond Magnifier of the Dou-
ble Microfcope.

My Way of difcovering them is, by plac-
ing a fmall Drop of the Water, wherein I
know they are, with fome of the Sediment
therein, under the third or fourth Magni-

, • Wheel Animais, though found with moll Certainty î»
Leaden Gutters, (âc. are often difcovered in the Waters of
fome Ditches, and likewife in Water that has flood 3
èonfiderable Time even in the Houfe : for I have often n^«'
with them, in fufficient Plenty, in a Sort of flimy Matter,
that is apt to be produced on the Sides of Glaffes and other
Yeffels, that are kept long with the Infufions of Hay or other
Vegetables ; and probably they are wafted thither by the Air»'
* hen in the Condition of littk dry Globules.

fier ; and, when I have thereby found them,
I change the Glafs for one that fliews them
larger, and then watch all their Motions
with great Attention.

This little Creature fhews itfelf at firft
(unlefs it be in its Globule Form) like a
tranfparent Maggot or Caterpillar, and ap-
pears lengthening out its Body confiderably
at fome Times, and at others contrading it
as much. Its Motion from Place to Place
is likewife then performed in the Manner of
fuch Infeds, fixing firft its Tail and extend-
ing its whole Body, then faftening its Plead
and drawing up its Tail to it: fothat by fix-
ing its Tail and pulliing its Body forwards,
faftening its Head and drawing its Tail
thereto, alternately, it works itfelf along
pretty nimbly. Vid:fig. i. 2. Plate XI.

But one ihall often behold it changing
this Appearance in an Inftant, and afiTuming
a Form extremely different; for its Snout
being pulled fomewhat imvard, the anterior
End becomes clubbed, and immediately di-
viding, exhibits, moft liirprizingly, to view,
a Couple of femi-circular Inftruments, before
unfeen, round the Edges whereof many little
Fibrilla move themfelves very brifkly, fome-
times with a Kind of Rotation, and fome-
times in a trembling or vibrating Manner. An
Opening or Mouth alfb appears in the Mid-
dle between thefe two Semi-circles. When in

this Condition, the Animal is often feen to
unfaften its Tail, and fwim along with a
great Deal of Swiftnefs, feemingly in Parfuit
of Prey. Vid. fig, 3.

The Subftance of this Animal feems to
be chiefly mufcular, every Part thereof be-
ing capable of great Diftention and Con-
traftion. It has likewife a confiderable De-
gree of Tranfparency, whereby the Syftole
and Diaftole of its Heart, and the periftaltic
Motion of the Inteftines, are rendered plainly
vifible: and a Kind of Undulation may be
perceived every where within it. It appears
ftrong and vigorous in Proportion to its Size,
and feems almoft continually hunting after
minute Animalcules or other little Bodies
wherewith the Waters abound.

Fig. I. fliews the Form of the Infeft
under Examination, when it appears
like a Worm or Maggot, and fully Ex-
tends its Body, Sometimes in this
Condition little Spiculce appear darted
^ out at the Head End, with a Sort of
vibrating Motion ; the Snout is alfo
lometimes more flat, and ftiarper at
other Times, than reprefented here.
Fig. 2. defcribes the Manner of its
moving from Place to Place whilft in
the Maggot Form, by bringing the
Head and Tail nearly together; then
ftretching the Body out, fixing the

Fig. 3. exhibits the Infeil with its two
femi-circular Parts put out, and exad-
ly in the Pofture it places itfelf, when
it prepares either to fwim away, or to
fallen by the Tail and work its Wheels
about.

The general Account already given, will,
it is hoped, render my Talk the eafier, now
I come to examine the moft diftinguifhing
Parts of this Animal; uiz. the Head, the
Thorax or Breaji, the Abdomen or Belly, and
the Tail:, each whereof I fliall defcribe with
all the Perfpicuity and Brevity the Subjeft
will allow.

The Fafhion and Conftructure of the Head
is wonderful, and extremely different from
that of any other Creature hitherto defcrib-
ed ; its fudden Change out of one Form
into another is alfo unufual and furprizing :
for, from being perfetliy tapering, and end-
ing almoft in a fharp Point, like the Head of
a common Maggot, it becomes on a fudden
as wide as any Part of the whole Infeft,
opens a large Mouth, and is furnifhed by
Nature with an amazing Piece cf Machine-
ry whereby to procure its Food.

One of thefe Animals, with the Head as
here defcribed, is reprefented fg. 4. where
a Couple of circular Bodies, armed with
fmall Teeth like tliofe of the Balance-Wheel
Vol, II.nbsp;Tnbsp;of

of a Watch, appear projedling forwards be-
yond the Head, and extending fideways
fomewhat wider than the Diameter thereof.
They have very much the Similitude of
quot;Wheels, and feem to turn round with a
confiderable Degree of Velocity, by which
Means a pretty rapid Current of Water is
brought from a great Diftance to the very
Mouth of the Creature, who is thereby
fupplied with many little Animalcules and
various Particles of Matter that the Waters
are furniftied with.

As thefe Wheels (for fo from their Appear-
ance I lhall beg Leave to call them) are every
where excefirvely tranfparent, except about
their circular Rim or Edge on v/hich the
Cogs or Teeth appear, it is very difficult to
determine by what Contrivance they are
turned about, or what their real Figure is,
though they feem exadlly to refemble Wheels
moving round upon an Axis.

It is alfo hardly poflible to be certain
whether thefe circular Bodies, round the
Edges of which the Teeth are placed, are
of a flat Form, or hollow and of a conic
Figure. But they appear rather to be the
latter; and if fo, they may be likened, not
improperly, to a Couple of fmall Funnels
with Teeth fet round their large Ends.
However, be they flat or hollow, they feem
plainly to be protruded from a Pair of tubu-
ar Cafes, into which they can be again re-

tradled at the Will and Pleafure of the Ani-
mal J and their Ufe undoubtedly is to pro-
cure it Food, by Means of that Current or
Vortex which the Motion of them excites.
They turn not always in the fame Manner,
nor with equal Svviftnefs, neither is the Ap-
pearance of their Teeth or Notches con-
ftantly the fame : for one ftiall fometimes
fee them moving in contrary Diredtions, and
fometimes turning both the fame Way. It
is alfo not unufual, after they have been
moving one Way for a confiderable Time,
to behold them ftop on a Sudden and turn
diredlly contrarywife. Their feeming Ro-
tation is fometimes very faft, and at other
Times very flow increafing or decreafing
fometimes gradually, and fometimes all a^
once.

The Teeth or Cogs of the Wheels feem
to ftand very regularly at equal Diftances:
but the Figure of them varies according
to their Pofition, the Degree of their Pro-
trufion, and perhaps the Will of the AnimaL
They appear fometimes like minute oblong
Squares rifing at right Angles from the Pe-
riphery of a Circle, like ancient Battlements
on round Tower; at other Times they
terminate in fliarp Points, and all together
refemble a Kind of Gothic Crown. ^They
are often feen in a curvular Direftion, all
bending the fame Way, and feeming like fo
many Kooks: and now and then one fliall

perceive the Ends of them to be chibbed, or
in Appearance like a Number of little Mal-
lets. This Figure, and the firft, they how-
ever aflimie but rarely.

When the Forepart of this Creature firft
• appears to open or divide, the Parts above
defcribed, which when fully protruded re-
femble Wheels, and feem to have a quick
Rotation, coming then but a little Way be-
yond their tubular Cafes, (and being in that
Condition like round Pieces of Paper folded
in the Middle, or Funnels whofe Sides are
flatted almoft together,) feem only like a
Couple of femi-circular Parts, about theEdges
whereof, what are feen afterwards like the
Teeth of the Wheels, appear only as little
Fibrillce or Spicida, having all a nimble and
continual vibrating Motion upwards and
downwards, whereby the Water becomes
greatly agitated, and brought to the Animal
from feveral Times the Diftance of its own
Length. Vid.fig. 3. *

Before it begins to fhew itfelf in this Pof-
ture, it frequently faftens its Tail to the flimy
dirty Matter found with it in the Water, or
elfe to the Glafs whereon it is placed for
Viewi and buoying up its Body in the Water,

* This Vibration commencing commonly fome Time be-
fore the Wheel-Work pufces out and exerts its rotatory Mo-
tion, fome People, not overllock'd with Patience, have con-
cluded, that it has no other Motion, than fuch a Vibration
of the Fibrilia ; but I am perfuaded a little more Attention
will convince them of their Miftake.

pufhes its Head forwards, dire6ling it this.
Way and that Way with a great Deal of Agi-
lity, and. feemingly in Search of Food. In
the mean While, many minute Animalcules
and other little Bodies are drawn along with
a rapid Current of Water, fome whereof are
taken in and fwallowed, and others rejefted,
though brought to the Opening of its Mouth,
which appears exaftly in the Middle, be-
tween the two above defcribed Semi-circles.

While the Sides of the Wheels are thus
doubled as it were together, there is little or
no Appearance of any circular Motion, the
Fibriilce about their Edges feeming to have
only a quick Vibration : but moft commonly,
after two or three Minutes, this extraordi-,
nary Apparatus becomes- protruded farther,
the two Semi-circles pufti out, and open at
the fame Time j each of them immediately
refembies a complete Circle or Wheel, feems
to turn round very regularly, and its little
• Fibriilce appear changed into Cogs or Teeth,
in the Manner above mentioned.

As the Anim il is capable of thrufting thefe
Parts out, or drawing them in, fomewhat
in the Way that Snails do their Horns, the
Figure of them is diftcrent in their feveral
Degrees of Extcnlion and Contratlion, or ac-
cording to their Polition to the Eye of the
Obferver, whereby they not only appear in
all the various Forms before reprefented, but
feem at certain Times as if the circular Rim

of the Wheel or Funnel were of fome
Thicknefs, and had two Rows of Cogs or
Teeth, one above and the other below that
Rim.

When the Wheels appear in Motion,
the Head feems large in Proportion to the
Size of the Animal; and tho' it is then
every where tranfparent, a Ring or Circle,
more particularly remarkable for its Clear-
nefs, may commonly be perceived about the
Middle of the Forehead, a little above the
Mouth. (See fig. 5. a.) I fliall not pre-
tend to call this the Seat of the Brain,
though its Situation and Appearance would
perhaps juftifyfuch a Suppolition; but as I
am fully fenfible how very eafy it is for me
to be miftaken, I am extremely fearful of
leading others into Miftakes. Many Veffels
which feem to take their Origin from hence
are difcernible in the Head, wherein fome
tranfparent Fluid appears continually agitat-
ed with a Sort of fluftuating Motion. All
thefe Velfels and every Part of the Head are
capable of great Diftention and Contrac-
tion, and frequently alter their Figure.

The Thorax or Breaft h, is joined to the
Head by the Interpofition of a fliort an-
nular Circle or Neck c, which is very
plainly diftinguifhed when the Infedt is
flretched out, and is working with its
Wheels. This Thorax is nearly one fixth
Part of the whole Animal, and deferves the

moft careful Examination ; for as the Heart
d may be feen therein more diftindtly, its
Figure and Motions may confequently be
obferved much better in this than in any
other fmall Creature I have met with.

The Heart d is placed almoft in the Mid-
dle of the Thorax, where its Syftole and
Diaftole can't fail to catch the Eye of every
attentive Obferver; for it is feen through
the Back of the Infedl very plainly, flat-
ting and opening, alternately, with great
Regularity and Exaftnefs. Its Size is pro-
portionable to the Creature's Bignefs, and
its Shape during the Syftole or Time of
Contraftion is nearly circular, being com-
pofed feemingly of two femi-lunar Parts,
which then approach each other, laterally,
and form between them a roundifli or Horfe-
ftioe like Figure, whofe upper Side is flat,
but the under one convex. The Diaftole is
performed by a feeming Separation or Open-
ing of thefe two femi-lunar Parts,quot; where-
by the tranfverfe Diameter of the Heart
is very much enlarged. This Separation
begins exaaly in the Middle of the lower
Part next the Tail, and opens to fuch a
confiderable Width upwards, that the two
Parts when at their utmoft Diftention feem
only joined by an arched Veflel at their
anterior End. The alternate Motions of
contraction and Dilatation are performed
with great Strength and Vigour, in pretty

much the fame Time as the Pulfations in
the Arteries of a Man in Heahh ; as I have
often proved by feehng my own Pulfe whilft
I have been viewing them. In each of the
femi-Iunar Parts there appears a Cavity,
which feems to clofe when thofe Parts come
together, and to open itfelf again when they
feparate.

The Motions of the Heart are communi-
cated to all the other internal Parts of the
Thorax-, and indeed feem to extend a great
Deal farther ; for a ftria Examination dif-
covers, at the fame Time, throughout the
whole Animal, Contradions and Dilatations
going on that are apparently correfpondent
thereto.

It is however neceffary to remark, that
thefe Motions of the Heart are, fometimes,
as it were fufpended, or unperceivable for
two or three Minutes, after which they be-
come renewed, and go on again with the
fame Vigour and Regularity as before. And
this Sufpenfion of the Syftole and Diaftole,
has made fome Gentlemen, to whom I have
fhewn it, doubtful, whether the Part we
have been defcribing can therefore be the
Heart. But their Doubt arifes wholly from
a Suppofition that the Hearts of minute In-
fedts muft continue beating with the fame
Conftancy, and be fubjeil to the fame Laws,
as the Hearts of the larger Kinds of Animals,
which probably is not the Cafe.

The Situation, the Size, the Contraâion,
and Dilatation of the Part we fuppofe to be
the Heart, all concur in Support of that
Opinion ; but they can hardly all agree with
any other of the Vifcera : and as to the Suf-
penfion of its Motion, fince in the Tortoife,
the Viper, the Frog, and perhaps many
other Creatures w^ho become torpid at fome
Seafons, the Motion of the Heart is fuf-
pended or unperceivable for a confiderable
Length of Time, there is no Abfurdity in
believing that the fame Thing may happen
to this Infeft, which is fometimes in a tor-
pid or inacliye State as well as they, without
doing it any Injury. Nay, that the Motion
of its Heart (whether this Part be it or
no) muft unavoidably be fufpended, whilft
this very Animal is contracted into a Ball,
and ,as dry as Duft, is, I think, highly pro-
bable.

Tloe Blood or circulating Fluid is fo ab-
folutely colourlefs in this Creature, that the
Current of it through the Veffels is undiftin-
guifliable by Glaffes, however likely it may
feem, from the ftrong Contraction of the
Heart, that a Circulation muft be carried
on, and that too very brifkly. One fees
indeed almofl every where a Sort of irregu-
lar Agitation of fome Fluid, which may be
perhaps the compound Motion of Currents
running ditferent Ways and forming fuch an

From the under Part of the Thorax a
fmall tranfparent Horn proceeds, which can
be never feen unlefs the Infed turns on its
Back or Side. I know not whether it be a
Diftindion of Sex, or to what other Purpofe
it may ferve; for thefe minute Animals
cannot poffibly be fo managed as to bring
it under Examination when one pleafes and
as it is only feen fometimes by Accident, I
cannot pretend to fay whether all or fome
of them only are furnifhed therewith. It
is fhewn in the Figures i and 2. a a. being
more commonly feen when the Creature is
in the Maggot Shape than at other Times.

Immediately below the Thorax is another
annular Circle or Divifion joining upwards
to the Thorax, and downwards to the Ab-
domen ; the Entrance whereof it ferves oc-
cafionally to enlarge or diminifh. This is
fliewn fg. S' at the Letter e.

The Abdomen or Belly f is much the
largeft Part of the Animal, and contains the
Stomach and Guts. When the Infed is full
of Food thefe Bowels appear opake and of a
Blood-red or crimfon Colour, extending in
Length from the Thorax quite through the
Belly and great Part of the Tail, and exhibit-
ing a fine View of the periftaltic Motion, or
fuch gradual Contradions and Dilatations as

feem intended to propel their Contents
downwards. Around the Bowels are many-
Ramifications of Veffels both longitudinal
and tranfverfe; and between the Bowels
and the Skin a Fluid exceedingly tranfparent
fludluates in a Manner Words cannot de-
fcribe.

The Belly is capable of ftretching out
greatly in Length, or being fhortened very
much and widening its Diameter : in fhort,
it affumes many Shapes, and becomes, on
Occafion, a Cafe including the whole Ani-
mal, as will by and by be fhewn.

From a Joint at the lower Part of the Belly
to the pofterior Extremity is what I call the
Tail. (Vid. fig. 5. g.) It has three other
Joints, to the lowermofl whereof the Bowels
extend themfelves, and appear contra6ling
and dilating upwards and downwards, tho'
not fo remarkably when they are empty as.
full. This Part runs tapering from the
Belly to its End, and is lengthened or fhort-
ened at the Creature's Will. When it is in-
clined to fix itfelf by the Tail to any Thing
(as commonly is its Way when it intends
to work with its Wheels) two, four, and
fometimes fix little tranfparent Hooks or
Fins may be feen thrufl out at its End, and
ferving for that Purpofe. They are placed in
Pairs : one Pair is at the very Extremity, and
the other two a little Way up the Sides; but
the three Pair are feldom feen together.

Though this Infed fwims very Aviftly, and
feemingly with great Eafe, neither Legs nor
Fins can be perceiyed to affift it in fo doing,
unlefs thofe juft now mentioned about the
Tail, and the Florn under the Breaft, may be
imagined fuch. Wherefore fince the Wheels
in its Head are always fet to work very
brifkly whenever gt; it begins to fwim, one
may reafonably prefume they are the Inftru-
ments by -which it performs this Office.
And, indeed, looking at the Manner of its
fvvimming through a Hand Magnifier, when
it is at large in a Phial of Water, will confirm
this Opinion greatly j for there one ftiall
often difcern it rifing in a perpendicular Di-
redion, and by the Rotation of its Wheels
climbing as it were upwards and mounting
through the Water; but finking down a-
gain inftantly upon the ceafing of their
Motion.

As I call thefe Parts Wheels, I alfo term
the Motion of them a Rotation, becaufe it
has exadly the Appeai'ance of being fuch.
But fome Gentlemen have imagined there
may be a Deception in the Cafe, and that
they do not really turn round, though
indeed they feem to do fo. The Doubt of
thefe Gentlemen arifes from the Difficulty
they find, in conceiving how, or in what
Manner, a Wheel, or any other Form, as
Part of a living Animal, can poffibly turn
upon an Axis, fuppofed to be another Part

of the fatne hving Animal ; fmce the Wheel
muft be a Part abfolutely diftinCt and fepa-
rate from the Axis whereon it turns -, and
then, fay they, how can this living Wheel
be nouriftied, as there cannot be any Veflels
of Communication between that and the
Part it goes round upon, and which it muft
be feparate and diftindt from ?

To this I can only anfwer, that place the
Objeft in whatever Light or Manner you
pleafe, when the Wheels are fully pro-
truded they never fail to ftiew all the vifible
Marks imaginable of a regular turning
round, which 1 think no lefs difficult to ac-
count for, if they do not really do fo. Nay,
in fome Pofitions, ,you may v/ith your Eye
follow the fame Cogs or Teeth whilft they
feem to make a complete Revolution j for,
the other Parts of the Infed being very
tranfparent, they are eafily diftinguiftied
through it. As for the Machinery, I ftiall
only fay, that no true Judgment can be
formed of the Strudure and Parts of minute
Infers by imaginary Comparifons between
them and larger Animals, to which they
bear not the leaft Similitude. However, as
a Man can move his Arms or his Legs, cir-
cularly, as long and as often as he pleafes,
by the Articulation of a Ball and Socket,
may not there pofllbly be fome Sort of
Articulation in this Creature whereby its

Having defcribed the moll: remarkable
Parts of this Infedt, I fhall, by the four fol-
lowing Figures, endeavour to reprefent fome
other of the mofl ufual Forms it affumes,
both when its Wheels are fully protruded,
and when the Edges only of them are fhewn
with their little vibrating Fibrillce.

Fig. 6. is the Wheel InfeB raifmg itfelf
on the Tail, flooping the Head down-
wards, and working its Wheels about.
This is a common Poflure, in which
the Back is bowed, and the Belly ap-
pears fhortened and diftended, great
Part of the Thorax being taken into it.
The Wheels in this Pofition feem to
turn horizontally, with their Backs up-
v^'ards and towards the Eye, in which
Manner they appear very diflindl arid
large, with their Teeth bending all the

* It is certain all Appearances are fo much on this Side the
Queftion, that I never met with any who did not on feeing it
call it a Rotation ; though from a Difficulty concerning how it
can be effefted, fome have imagined they might be deceived :
Mr. Leeuwnhoek alfo declared them to be Wheels that turn
round-, vid. Phil. Tranf. Nquot; 295. But I lhall contend with
nobody about this Matter : it is very eafy for me I know to
be miftaken, and fo far poflible for others to be fo too, that
I am perfuaded fome have miftaken the Animal itfelf, which
perhaps they never faw, whilft inftead thereof they have been
examining one or other of the feveral Water-Animalcules that
are furniihed with an Apparatus commonly called Wheels,
though they turn not round, but excite a Current by the
mere Vibration of FibrilU about their Edges.

fame Way, and refembling as many
Hooks. The different Parts of the
Animal, as before defcribed, are ex-
plained by this Figure.

Fig. 7. fhews the Animal turned with its
Side towards the Eye, as it frequently
prefents itfelf. The Wheels here have
the fame Appearance as in the pre-
ceding Figure : but one of them lies
confiderably below the other, the whole
Body being fomewhat twifled, whereby
the Horn under the Thorax is diflindtly
brought to View.

Fig. 8. and 9. exhibit two of thefe Crea-
tures in the Poflures they are often feen,
when the Wheels are not thrufi; out,
but the Fibrillcs appear moving up and
down with very quick Vibrations. We
fee particularly in fig. 9. the whole
Space between thefe Parts gaping like
a wide Mouth, and different from any
of the former Figures.

To defcribe the many Poflures I have
feen this Creature in would be a Wafle of
Time; but the Manner of its changing,
when it pleafes, into a round Globule or
Ball, is fo remarkable a Part of its Hiflory,
that I mufl attempt to give the beft Account
of it I can; as I have many Times obferved
very attentively every Step in its Metamor-
phofis.

various Directions, for two or three Hours,
in the Water, and probably filled its Belly,
(during which Time its Tail remains faften-
ed to feme Dirt or Slime, or to the Slip of
Glafs it is placed upon,) one fhall perceive
it, by Degrees, moving them with lefs Vi-
gour, and at lafl drawing them quite within
the Head. The Head and included Wheels
fink down then very flowly into the Thorax,
the Belly fwells, and the Whole appears like

Soon after, the Thorax alfo (which now
contains the Head and Wheels) is drawn
within the Belly, and below the annular
Circle at the Top of it, as fig. ii. repre-
fents.

The faid annular Circle then contracts,
and its Sides come together like the Sides
cf a Purfe when the Strings are pulled,
clofing over the Head and Thorax, which,
now, filling the upper Part of the Belly,
make it nearly round, like fig. 12.

In the laft Place, the three upper Joints
of the Tail come down over the lower Joint,
which becom.es fixed ; immediately the Belly
alfo finks, or is pulled down, and indoles
the whole Tail. All the Parts being now
included in the Belly, which becomes their
Cafe or Covering, it fwells into a round
Ball, lies without any Motion, and appears
confiderably opake. (Vid. fig. 13.) It flili
adheres however by the Tail.

Sometimes, when in the Maggot Form, it
tolls its Head and Tail together, without
drawing them into its Body; in the Man-»
ner offig. 14.

All my Endeavours have hden hitherto
unable to difcover how thefe Creatures pro-
pagate, though for three Years paft I have
never been without them, and am continu-
ally fenfible of their Increafe, by obferving
Numbers of extremely fmall ones appearing
from Time to Time : which undoubtedly are
young Fry. There's however good Reafon
to believe they proceed from Eggs : for I
have often feen, in the Water along with
them. Parcels of Ova, gelatinous like the
Spawn of Frogs, and of a Size proportion-
able to the Wheel Animal.—But after what-
ever Manner they are propagated, 'tis pretty
certain, from the exceeding Minutenefs of
fome in Comparifon of others^ that they
come out at firft in their perfed Shape, and
are not the Nymphce of any other Infedt, as
tnany Creatures found in the Waters are.

Mine have conftantly been kept in the
fame Glafs Vefi^el, fometimes with and fome-
times without Water ; for as the Sides of the
Glafs were often left dry, I have fuffered
thofe that had faftened themfelves there to
remain fome Months in that Condition:
neverthelefs, I always found them to become;
as lively as ever on giving them frefh Water.
Mr. Leeimenhoek kept fome Dirt, taken out
of a Leaden Gutter, and dried as hard as
Vol, II,nbsp;Unbsp;Clay,

Glay, for twenty-one Months together; and
yet when it was infufed in Water, Multi-
tudes of thefe Creatures foon appeared un-
folding themfelves,' and quickly after began
to put out their Wheels : and I myfelf have
experienced the fame with fome that had
been kept much longer.

All tlieir Actions feem to imply Sagacity
and Quicknefs of Senfation. At the leall
Touch or Motion in the VVater they inftant-
ly draw in their Wheels. Notwithftanding
their Smallnefs, one fees feveral Species of
Animalcules fwimmJng in the Water with
them, compared to which themfelves appear
like Whales. Thefe Animalcules are their
Prey : which they take either by Purfuit, or
draw to them by the Current of Water which
their Wheels excite.

It has conftantly been my Endeavour to
difcover the Eyes of this Creature, but I have
never been able to difcern that it has any.
And yet, when one beholds it fwimming
along with great Swiftnefs, turning its Head
on every Side, and feemingly purfuing its
Prey, avoiding any Dirt or other Matters
in the Water that Vv ould obftrud its Pallage,
and direding its Courfe with as much feem-
ing Care, Choice, and ConduCl as Animals
•that have Eyes do, one can hardly think it
deftitute of Sight.

I would induftrioufly avoid giving way
to Fancy in Cafes of this Nature, but muft

acknowledge nay fufpeding that it has Eyes
fomewhere within its Wheels : and my Rea-
fons for this Sufpicion are, its blundering, ir-
regular, and flow Motions while it ap-)cars
in the Form of a Maggot, before its Wheels
are put cut, and the Regularity, Swiftnefs,
and fl:eady Diredion of its Motions after-
wards : whereto I might add, that when it
fwims along its Wheels are always out. Be-
fides, all the Creatures wc know that move
themfelves from Place to Place with Swift-
nefs, either by running, flight, or fwim-
ming, are remarkable for their Keennefs of
Sight ; and indeed it feems probable that
the fame Rule may hold through all the
Animal Creation : for as the Gifts of Pro-
vidence are ever fuited to the Exigencies of
its Creatures, and contrived in the befl Man-
ner for their Prefervation, we can fcarcely
imagine Svviftnefs is beflowed on any with-
out the additional Bleflîng of Sight to direct
its Courfe ; flnce the former without the lat-
ter mufl; unavoidably precipitate the Creature
into continual Danger of Deflruftion.—This
makes me fuppofe it may poflibly have Organs
of Sight fomewhere about the Wheels : nor
is there any thing more extraordinary in that
than in the Eyes of Snails, which are gene-
rally allowed to be placed at the Extremities
of their Horns, and confequently mufl; be
thrufl; out and drawn in v/ith them.

I cannot conclude this Subjed; without
doing all the Honour I am able to the Me-
U 2nbsp;mory

mory of Mr. Leeuwenhoek, by repeatiiïgj»
that we are obliged to his indefatigable In-
duftry for the firft Difcovery of this moft
furprizing Infed.

H E R E are found in the Waters fe-
veral other Kinds of Animalcules,
furniihed with Inftruments for making an
Eddy, and thereby bringing to themfelves
fuch minute InfeCls, or very fmall Particles
of Matter, as ferve them for Food. Among
thefe fome appear to have a rotatory and
others a vibrating Motion ; fome alfo feem
capable of being employed both Ways.

In the Ditch-Water fent me from Nor-
ivich, as before-mentioned,233,1 difco-
vered feveral Wheel Animals with Tails enor-
moufly long, but in all other Refpeds, as far
as I could difcern, differing not at all from
thofe juft now defcribed ; the Motion of the
Wheels, the Pulfation of the Heart, and the
Undulation of the Bowels appearing exadly
the fame in both : Nothing therefore feems
farther neceffary than to give the Pidure of
them, which fee Fig. i. Flate XII.

Fig. 2 and 3 in the fame Flate, repre-
fent two different Sorts of Animalcules, feve-
ral whereof were found fome Years ago, in

Water taken out of a Leaden Ciflern that
ftood in Somerfet Garden.—The anterior
Part in the firft of thefe has a large Opening,,
furrounded with fliarp Spicid^e, a, and is evi-
dently cruftaceous, though the Body and
Tail are mufcular. It is not eafy to difcern
the Inftruments within this Mouth or Open-
ing that ferve to form a Current of Water,
ss the Creature does not thruft them beyond
the Neck b. When it fwims along it feems
extremely formidable to the minuter Ani-
malcules, Multitudes of which are frequent-
ly fucked in, together with a great deal of
Water, which is fpouted out again immedi-
ately. When the Tall is faftened to fome-
thing, it turns the Body about and diredls its
wide Mouth to every Side, and bringsaStream
of Water from a confiderable Diftance. The
Motions of the Bowels are diftindlly vifible
in this Animal; and within feveral of them
one may fee an opake oval Body c, Vv'hich by
its Size and Appearance I imagine to be an
Egg; which if it is, it fignifies their Increafe
to be much lefs than that of moft other mi-
nute Animalcules; for I never obferved more
than a fingle one in any of them; and in-
deed I never found the Creatures themfelves
in very great Number. They are fomewhat
larger than the common Wheel Animal.

Fig. 3. reprefents an Animalcule found
in the fame Water with the former, and re-
fembling: it pretty much in the ■ Size and
U 3nbsp;Shape

294 Btfferent Wheel Animals,
Shape of its Body, though its Head and Tail
are different: for this Creature's Tail is fur-
nifhed with a Couple of Inftruments a a, that
lie flieathed therein, unlefs Avhen they are
made ufe of to faflen it to any Thing, that
it may the better be enabled to occafion an
Eddy of Water and bring its Food to it with
the Stream. During the Time it is fo em-
ployed the Body appears extended (as in the
Figure) and a Number of Fibriilce, protruded
from two prcjeaing Parts b b that compofe
the Head, put the Water into a violent Mo-
tion, and excite a Current, by their vigorous
and quick Vibrations, which fets direfrly
towards the Mouth c.

This little Creature is entirely mufcular,
and frequently changes the Form of its Ap-
pearance by contracting its Body and pulling
in its Head or Tail. The periftaltic Motion
of its Bowels, which are confiderably opake,
is feen working upwards and downwards in
an odd Manner, but no Part can with any
Certainty be known to be either Luno-s,
Heart, or Stomach. In many of them how-
ever, an oval Body, which I guefs to be an
Egg, is very diflinguifliable, contained feem-
ingly in a Uterus, or Veffel, that feparates it
from the oth er Bowels. They lived with me
feveral Days in the Vv'ater they were brought
in, but I could never be fo lucky to fee any
of thefe Eggs, (if fuch they are) difcharged
from the Animal.

IN the Summer of the Year 1745, I firft
took Notice of three Sorts of V/heel Ani-
mals ¹ having Shells, which I found herding
together in the Water of the Ciftern in the
Garden of Somerfet Houfe, and have feen
fince in other Waters. The firft of them is
reprefented by the Figures 4, 5, 6 : the fe-
cond Sort by thofe 7, 8, 9, 10: and the
third Sort are marked 11, 12, 13. Plate
XII.

The firft Sort when extended is in Length
about twice its Breadth. It is contained in a
Shell, whofe Fore-part or End is armed with
four very long Spikes on one Side of its
Rim, the other Side whereof has no Spikes,
but is waved or bent in tv/o Places, much
like the Form of a Turkifh Bow: vid.
fig. 6. The pofterior End has a large cir-
cular Hole through which the Tail is piit
out. By this Tail it faftens itfelf to any
Thing it meets with, when it intends to fet
the Wheel-work at its Head in Motion;
but in fwimming, and at all other Times
v,'hen it is not fixed by it, it wags this Tail
backwards and forwards as a Dog does his,

1nbsp; Thefe are called Wheel Animals, from their refembling
the foregoing in feme Particulars.

and makes ufe of it on other OccafionSa
which we lliall prefently take Notice of.

Its Body feems divided into three Parts,
the Plead, Thorax, and Abdomen : each
whereof is capable of great Diftention and
Contradtion; the Creature being able by
extending them all three to protrude its
Head beyond the Shell, and on the contra-
ry, by contrafting them, to draw its whole
Body a great Way v/ithin the fame.

The Head when extended divides into
two Branches, between which another Part
(a Kind of Probofcis) is puftied out, at
whofe End are two Fibrils, that appear
when at Reft like one very broad Spike, but
which it can move very brilkly to and from
each other with a vibrating Motio?i, bring-
ing thereby a Stream of Water to its Mouth,
whofe Situation is juft betwixt them. And
the better to eifed this, feveral of the like
Fibrin^ are placed on each Side of the Head,
■lyhich vibrate in the fame Manner, as do
likewife fome very fmall ones at either Cor-
ner. All this may be underftood by view-
jngA- 4-

But fometimes it alters the Form of the
two Branches, rounding the Ends thereof,
and changing the vibrating Motion of its
Fibrilla: into a Rotation, or at leaft what
feems to be fo; at which Time'the Hea4
appears as ztjig. 5.

Immediately to the lower Part of the ,
Head the Thorax is joined, feemingly of
a mufcular Contexture, and containing with-
in it an Intefline, which by its Motions muft
be either the Lungs or Heart of the Ani-
mal ; fee b.fig, 4. and 5.

A Communication between the Thorax
and the Abdomen or Belly is continued by
Means of a fhort Veffel c, whofe alternate
Contractions and Dilatations occafion the
Abdomen to rife and fall alternately, having
at the fame time a Sort of periftaltic Mo-
tion. Through this Veffel or Gut all the
Food the Animal takes in is conveyed direil-
ly to the Abdomen, where it becomes digeft-
ed, and is then difcharged by the Anus, which
is placed fomewhere near the Tail; but we
have not yet been able to difcover exadlly
where, for the Fzeces are thrown out fome-
times at the lower Opening of the Shell,
and fometimes they are carried upwards
(between the Shell and the Body of the
Animal) and caft out with a confiderable
Force at the other End, by the Motions of
the Fibrillz, which the Animal can employ
to form a Current, not only towards him
but from him.

The Tail has three Joints, and is cleft or
divided at its Extremity, by which Means it
can the better faffen to any Thing. It is feen
moft commonly iffuing through the Hole
^t the lower End of the Shell, wagging nim-
bly

bly to and fro, and is made ufe of in fwim-
ming to fteer or direft its Courfe : but when
the Water wherein the Animal abides is al-
moft dried away, or when it has a Mind to
compofe itfelf to reft, it contraâs the Head
and Fore-part of the Body downwards, and
pulls the Tail upwards, in fuch a Manner
that the whole Animal is brought intirely
within the Shell : and at fuch Times only
the anterior Edges of the Shell, and the
Spikes proceeding therefrom, can be fully
diftinguiflied, and determined to be as repre-
fented fig. 6. whofe Defcript ion was juft now
given. For the Shell is fo extremely tranf-
parent that its Terminations cannot be feen
when the Infeft extends beyond it : but
whatever paffes within it is as plainly viftble
as if there was no Shell at all.

■Fig. 7, 8, 9, and 10, ftiew the feveral
Appearances of the fécond Species of thefe
fhelled Animals having Wheels, which dif-
fers from the firft in fome Particulars now
to be defcribed,quot;

The Body of this Species confifts of three
Parts, in like Manner as the other does ; only
the Thorax and Abdomen are not in this
feparated by a Gut or intermediate VefiTel as
they were in that, but are joined immediately
together j and at that Place in the Thorax,
where, in the other Species, I have defcribed
an Inteftine, which I fuppofed to be either
the Lungs or Heart, an Heart is plainly per-

ceived in this, having a regular Syftole and
Diaftole, and nearly of the fame Form and
Size with the Heart of the common Wheeler,
as the Figures 7, 8, and 9, are intended to
iliew at the Place marked a.

This Species likewife draws its Head and
Tail occalionally within the Shell, as z.t fig.
20; and then its Shell appears terminated
on its Fore-part by fix ftiort Spikes on one
Side of the Rim and two on the other, in-
ftead of the four long ones wherewith the
firft Sort is armed : but this does not always
protrude its Head like the other, fo far out
as to cover the Edges of the Shell intirely:
fometimes on, the contrary, the Spikes of the
Shell are feen beyond the Head, and the
Fibriilce mentioned in the former Defcrip-
tion appear playing between them, as at fig,
7. Hov/ever the Head very commonly is

As to their Propagation, both Species car-
ry their Toung in oval Saccidi or Integu-
ments, fa'.lened, externally, to the lower Part
of their Shells fomewhere about the Tail:
Thefe Sacculi are lometimes opake only at
one End, and feemingly empty at the other,
fsej%. 5 : Sometimes the Middle Part ap-
pears opake with a Tranfparency all round,
like fi.g. 7 ; and much Variety of Darknefs
and Tranfparency may be diftinguiftied, ac-
cording

It is highly entertaining to fee a young one
burff its Integuments, and gradually force
its Way through them : in doing which the
Parent is greatly affiffant, for by wagging
her Tail to and fro, and ftriking the Shell,
Skin, or Covering, brifkly therewith, the
young one's Head Part becomes as it were
fqueezed forvs^ards into the Water, tho' the
Tail cannot fo foon be difengaged. In this
Condition the young one fets its Wheels
a-going, and exerts all its Endeavours, 'till
at laft it frees itfelf from Confinement, and
fwims away, wagging its Tail as the old one
had done before it, and leaving the Integu-
ment adhering to the Shell of the Parent;
who then ufes Abundance of Contrivances
and Efforts to get rid of it, ffriking againft
it with her Tail, fixing the End of her Tail
thereto and darting her Body forwards, with
feveral other very odd Motions not eafy to
be defcribed.

A young one almoft difengaged from the
Shell, being faftened thereto only by the
Tail, is ftiewn jig. 9. h. The Subjedt from
whence this Pidure was exactly taken,
during the Performance of all the Particu-
lars above defcribed, had alfo another JSw-
brio, c, adhering to its Shell.

Thefe Animals have one, two, three, nay,
fojnetimes even four or fi,ve of thefe young

ones hanging to them : but they are fre-
quently without any at all, like the Figures
4 and 8.

The third Species of cruftaceoUs Animals
with Wheels, fhewn fig. 11, 12, 13. is re-
markably different from the former two in
the Shape and Fafhion of its Shell, which
extends on either Side a curved or hooked
Procefs, that bending towards the Tail, in-
ward, ends in a fharp Point, and is within a
fourth as long as the Tail itfelf.—The Head
Part of the Shell differs alfo from thofe be-
fore defcribed, in the Order and Difpofition
of the Spîciilœ, of which it has four longer
and two fhorter ones, placed as ivifig. 13.
where by the Body's being contraded and
drawn confiderably within the Shell, as fre-
quently is the Cafe, the Top of the Shell
is perfe6lly diflinguifhable, and its Spiculce
plainly feen.

The Tail of this Creature has the like
Figure, Articulations and Motions with that
of the other Species : and its Body may pro-
perly be divided in the fame Manner as
theirs, though in Shape it appears fomewhat
different through the Shell, which the
Drawings exprefs fufficiently without any
particular Defcription.

From its Head two Arms or Branches are
frequently extended, and the circular End
of each is furnifhed with a Border of Fibril-
la, feeming at fome Times to have a very

quick Vibration, and at others a rotatory
Motion, occafioning a rapid Current in the
Water.

Their Ova are carried at the Tail End,
either faftened to the Tail itfelf, or to the
Proceffes of the Shell, as at fig. 12. One,
two, or three are the Number ufually hang-
ing to them ; but fome, though very few,
have four or five. The I'oung burft their
Integuments, and are hatched very probably
like the Species before defcribed; but hav-
ing never had the Pleafure of feeing them
do fo, I can fay nothing more to this Part
of their Natural Hiftory.

A True Figure and Defcription of this
little Creature having never yet been
publiflied amongft us, what follows I hope
may prove acceptable.

The Name given it by Swammerdam, of
Pulex aqiiaticus arboreficens, I chufe to retain
here, as exprefling aptly enough its Motions
and Appearance.—It is found in Refervoirs
of Rain Water, in Bafons, Ponds, Ditches,
iSc. where the Water is not often renewed j
and that fometimes in fuch Abundance, a^

This Animal is cruftaceous, being covered
with a thin oval Shell in the Manner of a
Lobfter or Cray-Fifli, but with this Diffe-
rence, that the Shell being open a good Part
of its Length, the Animal can thereby put
out and draw in its Legs and Part of the
Body when it pleafes.

The upper Part of the Shell bears a near
Refemblance to the Head of a Bird, hav-
ing a fharp-pointed Procefs very much like
a Beak or Bill, but intirely fixt and immove-
able ; and the Eye being placed near there-
to, in a Situation much correfponding with
that of a Bird, adds much to the Refem-
blance, This Eye feems compofed of feveral
fmall Globules, though not pearled as thofe
of Land Infefts, but all contained in one In-
tegument, wherein they appear to be in fome
Degree moveable. The Animal has two of
thefe Eyes: but as he always lies on one
Side when placed in a Drop of Water to be
examined by the Microfcope, no more than
one can then be feen; which induced Mr.
Bradley to imagine it had only one Eye, and
from thence to call it Monoculus % but who-
ever beholds the monftrous Pidture that

• Some Swarms of them are red, and others green ; but
whether this Difference be owing to their Food, or fome
other Accident, or whether they are of diiTercnt Species, I
am unable to determine.

Writer has given of this Infed in his Book
on the Works of Nature, will be little fur-
prized at any of his other Miftakes.

A little below the Eyes, two Horns, which
are moveable, are joined to the £helly Head
their Infertion being in the Manner of Ball
and Socket. Each of thefe Horns comes
out in one fingle Trunk at firft, but divides
foon into a Pair of Branches, each Branch
having three Joints. A fmall Hair Briftle
grows out from either of the two firft Ar*
ticulations, and three pretty long ones from
the Extremity of the laft.

Juft beneath the Infertion of thefe Horns
a long Kind of Gut runs down almoft the
Length of the whole Body, where it joins
to a Part which in Shape very much refem-
bles the Toe of a Bird, having a large
Claw or Talon at the End thereof. The
Creature can move this Part beyond its Shell
with a great deal of Force, and by that
Means, as I apprehend, perfornis its fpring-
ing or leaping Motion.

It has eight Legs or Fins befides this,
which, when the Creature lies otherwife
ftill, are neverthelefs in a continual and nim-
ble Motion, forming a brifk Current of Wa-
ter, like that of many other Animals. They
are alfo very ferviceable in fwimming, and
afiift in its circular Motion, of which I fhall
prefently fpeak.

Behind the abovementioned Gut, and as
it were detached from the reft of the Body,
the Heart is placed, and may be feen dilat-
ing and contradtirig, alternately, with a very
regular and diftindt Syftole and Diaftole.

The lower Part of the Shell terminates
in a long Spike or Tail, which is without
Motion, but thickly fet with fix Rows of
ftiort ftrong Spines, making its Appearance
like the prickly Horn or Snout between the
Eyes of Lobfters, Cray Fifti, Shrimps, amp;c.

Swammerdam has very judicioufly ob-
ferved * (what every Body who examines
it carefully will difcover to be true) that this
Animal has three dift'erent Kinds of Motion.
The firft is a fmooth and even fwimming,
whereby it carries itfelf horizontally along
in the Water. The fécond is a fudden fkip-
ping or leaping, much refembling that of a
Flea. And the third is, when lying at the
Bottom of the Water, it turns its whole
Body round as it were on a Center, with a
Very brifk Rotation, by Means of its fmall
Legs or Fins.

As no Creature lives without its Tormen-
tors, this is very much infefted by the Shelled
Wheel Animal already defcribed. Page 298,
and ftiewn in the Plate with this, 7, 8, 9,
Both thefe Infedls are in great Abundance
frequently in the fame Water; and when that

is the Cafe, it is not uncommon to difcover
five or fix of the Shelled Wheel Animals faf-
tened by their Tails to the Shell or Horns of
the Water-Flea, and caufing to it feemingly
a vafi: deal of Uneafinefs; nor can they be
driven away, or fliaken off, by all the Mo-
tions and Efforts the Creature makes ufe. of
for that Purpofe.

I Was firft informed of this Creature by my
induftrious Friend Mr, William Arderon,
towards the End of the Year 1743, as his
Letters fhew ; and in the Year 1744» it was
taken Notice of by Mr. Trembley, who gave
it, in his Memoires, the Name of tlie Polype a
Pannaehe, or Plumed Polype. My Friend,
who difcovered it in his Searches for the
Polype, called it the Bell-Flower Animal-,
and after favouring me with his own Qb-
fervations, fent me fome of the Creatures
themfelves, which living with me feveral
Months, I had fufficient Time and Qppor-
tunity to examine and confider them. And
as there feems fome little Difference between
thofe in my keeping, and what Mr. Trembley
defcribes, they may poflibly be of another
Species, thpugh of the fame Genus.

This is one of the many Kinds of Water
Animals which live as it were in Societies:
of which fome Sorts hang together in Cluf-
ters, but can detach themfelves at Pleafure;
whilft others again are fo intimately joined
and conneded together, that no one feems
capable of moving or changing Place with-
out affeding the Quiet and Situation of all
the reft. But this Creature forms as it were
an.intermediate Gradation between the other
two, dwelling in the fame general Habita-
tion with others of its own Species, from
whence it cannot intirely feparate itfelf; and
yet therein it appears perfedly at Liberty to
exert its own voluntary Motions, and can
either retire into -the common Receptacle,
or pufti itfelf out from thence and expand
its curious Members, without interfering
with or difturbing its Companions.

They dwell together, from the Number
of ten to fifteen (feldom exceeding the lat-
ter, or falling fliort of the former Number)
in a filmy Kind of mucilaginous or gelati-
nous Cafe ; which out of the Water has no
determined Form, appearing like a little
Lump of Slime, but when expanded therein,
refembles nearly the Figure of a Bell with
the Mouth upwards j and is ulually about
the Length of half an Lich, and one Quar-
ter of an Inch in Breadth or Diameter. This
Cafe being very tranfparent, all the Motions
of its Inhabitants may be difccrned through

it diftindly. It feems divided, internally,
into feveral Apartments, or rather to con-
tain feveral fmaller Sacculi, each of which
inclofes one of thefe Animals. The Open-
ings at the Tops of thofe Sacculi are but juft
fufficient to admit the Creature's Head, and
a very fmall jPart of its Body, to be thruft
out beyond them, the reft remaining always
in the Cafe. The Animal can however when
it pleafes draw itfelf intirely down within the
Cafe, which is an Afylum to fecure it from
its Enemies (for it is not unlikely many of
the larger aquatic Infeds prey upon it) and
a fafe and agreeable Retirement wherein to
perform the Fundions of Digeftion, Sleep,
and the other neceftary Calls of Nature.
This Cafe it can, I fay,, retire into at Plea-
fure * and it never fails to do fo when any
fudden Motion of the Water, or of the Vef-
lel it is in, difturbs it : as alfo when it has
feized with its Arms any of the minute In-
feds which ferve for its Food.

The Arms are fet round the Head to the
Number of forty, having each the Figure
of a long f, one of whofe hooked Ends is
fiiftened to the Head ; and all together when
expanded compofe a Figure fomewhat of a
Horfe-fioe Shape, convex on the Side next
the Body, but gradually opening and turning
outwards (feeßg. 19 and 20, Flate XII.) fo
as to leave a confiderable Area within the
outer Extremities of the Arms. And when

thus extended, by giving them a vibrating
Motion, the Creature can produce a Current
in the Water, which brings the Animalcules,
or whatever other minute Bodies are not be-
yond the Sphere of its A6tion, with great
Velocity to its Mouth, whofe Situation is
between the Arms : where they are taken
in, if liked, or elfe, by a contrary Current,
which the Creature can excite, they are car-
ried away again : whilft at the fame Time
other minute Animalcules or Subftances,
that by lying without fide the Inclofure
made by the Arms are lefs fubjedi to the
Force of the Stream, are frequently feized
by them : for their Senfe of Feeling is fo
exquifite, that on being touched ever fo
flightly by any fuch little Body, it is caught
immediately and conveyed to the Mouth.
However, one may obferve the Creature is
fometimes difappointed in its Acquifition :
for after drawing down one of the Arms
fuddenly inwards towards the Mouth, it may
he perceived flowly extending itfelf again,,
without the Creature's retiring into its
Cafe ; which it fails not to do on meeting
With any thing worth its while.

The Food is conveyed immediately frona
the Mouth or Opening between the Arms,
through a very narrow Neck, into a Paflage
•feemingly correfpondent to the Oefophagus
in Land Animals; down which it pafles into
the Stomach, where it remains for fome

■-i-jj
il

't
«CI

Time, and then is voided upwards, in fmall
round Pellets (which at firft I imagined to
be its Eggs) through a Gut, whofe Exit is
near the Neck, where it was firft taken in.

The Body of this Animal confifts of three
Parts or Divifions, in the uppermoft whereof
all the aforementioned Inteftines are con^
tamed, though they are not to be diftin-
guiftied when the Creature is hungry; but
after it has eaten they become diftended and
opake^ and may very plainly be difcovered.
The other two Divifions (the lowermoft of
which I take to be fixed to the Bell or out-
ward Cafe) feem of no other Service than to
give the Creature Power of Contraftion and
Extenfion.

The Arms feem not able like thofe of
the common Polype to contrail or ftiorten
themfelves j but inftead thereof, when the
Animal retires into his Cafe, they are
brought together in a clofe and curious Orr
der, lb as eafily to be drawn in. Their gene-
ral Figure, when expanded, is that of a Cup,
whofe Bafe and Top are of an Horje-poe
X' orm j but they prefent fometimes a very
different Appearance, by feparating into four
Parts, and ranging themfelves in fuch Sort
as to reprefent four feparate Plumes of Fea-
thers.—Seefg. 22.

1 could never difcover any Eyes they
have, and yet find fome Reafon to believe
they fee : for on being fet in the Light of the

Sun, or a Candle, or brought out of the Dark
into the Day-light, though contradled before
and retired into the Bell, (as indeed they ge-
nerally are when in the Dark) they con-
ftantly extend their Arms for Prey, and ftiew
evident Signs of being pleafed.

Befides the particular and feparate Motion
each of thefe Creatures is able to exert with-
in its own Cafe and independent of the reft,
the whole Colony has together a Power of
altering the Polition, or even of removing
from one Place to another the Bell or com-
mon Habitation of them all. Plence this
Bell is feen fometimes ftanding perfectly up-
right {z-sjlg. 15 and 17.) fometimes bending
the upper Part downwards {^s Jig. 16.)

It has been mentioned already, that be-
tween ten and fifteen of thefe Animals dwell
together, as it were a little Community, in
one Bell-like Cafe or common Habitation :
but their Number increafing, this Bell may
be obferved to fplit gradually, beginning
from about the Middle of the upper or an-
terior Extremity, and proceeding downward
towards the Bottom, till they feparate at
laft intirely, and form two compleat Colo-
nies, independent of each other; one of
which fometimes removes itfelf to another
Part of the Veffel. The Manner how the
fingle Animals propagate, I have never been
able perfectly to difcover, though there is
fome Reafon to conjecture it may be by the
X 4nbsp;Means

Means of Eggs as fmall opake Bodies of a
conftant and determinate Figure are fome-
times feen lying in their Bells : and unlefs
they are Eggs I know not what to make of
them. Their Shape is nearly that of a
Weaver's Shu:tie, being compofed of two
circular Arcs, whofe concave Parts are to-
wards each other. The Breadth is about
two Thirds of the Length, and in the Mid-
dle of each a circular Spot appears more
opake than the reft, which poffibly may be
the Embrio. But as I never faw any of
them come to Perfedion, I can make no
farther Judgment of them than what their
Situation and Form fuggefts, They are re-
prefented15.

The Bells, or Colonies of thefe Animals,
are to be found adhering to the large Leaves
of .Duckweed and other Water Plants; and
may eafieft be difcovered, by letting a Quan-
tity of Water, with Duckweed in it, ftand
quietly for tliree or four Hours in Glafs
Veffels, in fome Window, or other Place
where a ftrong Light comes : for then, if any
are about the Duckweed, they will be found,
on careful Infpedion, extending themfelves
out of their Cafes, fpre;iding their Plumes,
and making an elegant i\ppearance.

They are extremely tender, and require
no little Care to preferve them : their moft
general Diforder is a Kind of Slime or ra-
ther Mouldinefs, which will fometimes enr

■ydope them in fuch a Manner as to prove
mortal. The beft Way of curing this is,
by gently pouring a large Quantity of Water
(perhaps two or three Quarts) into the
Veftel where they are kept, and letting it
run off flowly : by which Means the Slimi-
nefs will gradually be loofened and carried
away with the Water.

As to Food, if frefh Water be given them
daily, they will findfuflicient for themfelves;
and it is dangerous to try any other Way of
feeding them, for the fmalleft Worms, or
other viflble Infeds one can think of giving
them, will tear their delicate Frame in Pieces.

Flg. 'i^. reprefents one compleat Colony
or Bell, ftanding eredl, with all the Ani-
r4ials out of their Cafes, and their Arms ex-
tended for Prey : exhibiting all together a
very pretty Appearance. Here a fhews the
Gpake Bodies fuppofed to be Eggs.

Fig. 16. fhews all the Creatures with-
drawn into their Cells, and the End of the
Bell inclining downwards.

Fig. 17. the Bell ere6l, vi^ith only one of
the Animals coming out, in order to fhew
its Connedion with the Bell.

Fig. 19. one compleat Animal, greatly
magnified, to fhew its feveral Parts more
diftindly. Fiz.

f,nbsp;the Gut or laft Inteftine, through
which the Food paftes, after being
digefted in the Stomach.

h,nbsp;i, that Part of the Bell which fur-
rounds the Body of the Animal, and
clofes upon it when it retires down.

Fig. 21. The Head and Arms clofing to-
gether, and difpofing themfelves in order to
be drawn down into the Bell.

Frequently have taken Notice, in feveral
__ Infufions of Vegetables, of a little cruf-
taceous Animalcule, whofe Pidure is given
fg. 25th of this fame Plate XIL The Shell
of this Creature is fo exceedingly tranfpa-
rent, that unlefs great Attention be given
it cannot be difcerned at all. It feems to
cover the Back only of the Animal : its Bel-

1y, and under Parts, appearing to have no
Shell. The Middle of the Body, containing
the Bowels, (whofe periftaltic Motion may
be difcerned) is fomewhat opake, and in
the Shape of a Bottle with the Mouth down-
wards ; the Sides are tranfparent, and ftiew
many Veffels running through them. Four
Legs, or Fins, divided near half their Length,
and ferving either to walk or fwim, iffue
from the opake Part, and reach beyond the
Edges of the Shell : and two thicker and
ftiorter Limbs, pointing diredly forwards,
each of them armed with a ftiarp Claw, are
placed at the Head-End, and probably are
the Inftruments wherewith it takes its Prey.
On each Side of the narrow Part of the
opake Body, at fome little Diftance there-
from, one fees a round black Spot, the Ufe
whereof I don't pretend to guefs.—This Ani-
mal is brilk and vigorous, fwimming fome-
times with great Swiftnefs through the Wa-
ter, at other Times it creeps along at the
Bottom of the Drop, and now and then ikips
nimbly like a Flea. It often ftiews itfelf in
Profile, as reprefentedJig. 23.

Monfieur Joblot (whofe Imagination has
frequently exaggerated the Figures of Ani-
malcules to be found in Water,) tells us, that
he once difcovered, in an Infufion of the
Anemony, an Animalcule having on its Back
a Mafk or exad Reprefentation of a Satyr s
Pace-, and he gives a Pidure fuitable to that
7nbsp;Idea.

Idea. But, making a confiderable Allowance
for the Fruitfulnefs of his or his Painter's
Fancy, I think it not unlikely that the Sub-
jedl we are treating of might have been the
little Animal he faw : for the two black
Spots, with the Part of the Bowels that comes
between them, have fome Refemblance of
a Nofe and Eyes ; the two Points, which
terminate the Shell at the Tail-End, appear
fomething like a piqued Beard; the Dif-
tance between may pafs for a Mouth, and
the Whole' put together, might by a true
Lover of the Wonderful, be worked up to
the extravagant Likenefs of a »S^z/yr's Face.—
But this is mentioned only by the by, and
as a Reafon why I give it the Name of
Satyr.

rr-^OWARDS the End of September, in
X the Year 1743, fome Water taken
from a Ditch at Tooting in Surry, (wherein
many Polypes of an exceeding fmall Kind
had been difcovered, by my worthy, inqui-
fitive, and obliging Friend the Rev. Dr. Hen-
ry Miles, F. R. S.) was fent to me in a Phial,
in order to be examined. And whilft I was
viewing the Polypes with the Microfcope, I

iiad the Pleafure of finding three different
minute aquatic Animals, which I had never
before obfcrved.

The firfl of thefe feemed to the naked Eye
like a very fmall and flender Worm, of a-
bout one Third of an Inch in Length : but
the Microfcope foon fhewed jts real Form,
and the Singularity of its feveral Parts, in
the Manner they are reprefented Plate XII.

From the Fore-part of the Head of this
Animal a long Probofcis, Horn, or Snout was
extended, moving itfelf every Way with
great Readinefs, and iffuing from that Part
of the Head where the Mouth fhould be ;
which anterior Part changed its Appear-
ance according to the Motions of the Inftru-
ment, fometimes extending itfelf and becom-
ing more flender, and at other Times fhorten-
ing itfelf and growing thicker. About the
Head it had fomewhat of a yellowifh Colour,
but all the reft of it was throughout per-
feftly colourlefs and tranfparent, except the
Inteftines, which were confiderably opake,
and difpofed as in the Pifture. In them al-
fo a periftaltic or internal Motion was dif-
tindtly vifible. Along its Sides were feveral
Papiiy with long Hairs growing from them:
its Tail ended very bluntly : it had two black
Eyes, and was extremely nimble.

I found only this fingle Animal of its
Kind, from which I drew up the above Re-
marks

marks at the Time of viewing it, when its
Figure was likewife carefully taken j but
foon after I had the Favour of a better Ac-
count in a Letter from Dr. Miles, who had
Plenty of them under his Infpedtion : and
this I fhall lay before the Reader in the
Doftor's own Words.

quot; The Worm found in the Water in which
quot; I met with the Polypes in this Neighbour-
quot; hood is ofvarious Sizes, from about Vo of an
quot; Inch to half an Inch, and about theThick-
quot; nefs of the Worms we feed the Polypes
quot; with. It is tranfparent, excepting in the
Middle where the Gut runs, which the
Fsces make look of a dirty Colour, but it
has no Rednefs as the Worms have, and
quot; for that Reafon might be reckoned a-
quot; mongfl: the Infeds which fome have
quot; erroneoufly called exanguious, fince our
quot; Eyes, affifted by Glaffes, fhew them to
quot; have Blood : as I fhall prefently tell you
this has.

quot; The Form of it (when magnified I
mean) refembles in many Particulars fome
of our Caterpillars that feed on Vegeta-
quot; bles. It is infected as they are, and it is
quot; hairy: here and there a little Tuft of
quot; Hairs, and in other Places a fingle Hair
quot; regularly.growing out of the Sides, as I
have attempted to reprefent in the Fi-
gure. I faw the periflaltic Motion of
the Gut, and once faw it exclude Fasces,

three or four Clufters together, which re-
fembled exadly thofe of our common
Caterpillars, or of the Silk-worm Cater-
pillar. But the moft remarkable Thing
in this Creature is a Kind oiHorn or Feeler
which it feems to carry in its Mouth, and
may be juft feen by the naked Eye if
your Water be clear. 'Tis in the larger
ones about A Inch long. This (I know
not vvhat to call it) it waves to and again
as it moves in the Water, or when it
creeps up the Side of the Glafs; which
it does fomewhat like a young Leech, but
without contracting its Body fo much, and
rather in the Manner that Caterpillars do.
quot; I have not been able to learn, though
I have viewed it a long Time together,
whether it gets any Food with this Horn,
nor can I find whether it be hollow: but
I am certain 'tis not pointed, but rather
blunt: nor have I ever feen it contracted
any thing confiderably.—I muft not omit
to tell you, that 'tis a very tender Crea-
ture ; for in taking up the firft I viewed
with a Qiiill, as we do the Polypes, by the
Side of the Glafs, I injured it fo much,
that it was nearly cut in two, and its
Horn came oftquot;, after it had been a little
while in the Drop of Water upon the
Slip of Glafs. I was glad of this laft Ac-
cident, as it gave me an Opportunity of
obferving the Horn or Feeler in a better

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Manner than I could otherwife have done ^
for hereby it appeared to me to have growri
into the Fore-part of the Head or Mouth,
and to have been placed (as fome Bones
are) in a Socket, the End next the Head
feeming claviculated or clubbed, and con-
fiderably bigger than the other: the Head
quot; alfo in the Place where this Horn had
quot; been inferted was left with a Hollow fuit-
quot; able to fuch Articulation. I am doubt-
ful whether the Creature can contraft this
Horn or not, nor can I tell whether there
be any Communication between it and
quot; the Entrails. I took Notice that in or-
quot; der to wave it about confiderably it con-
tra6ted its Head a little, as if to hold it
quot; fafter and have moi-e Command of it; and
quot; indeed the Head refembles a Sort of For-
quot; ceps grafping this Feeler at the thick
quot; End.

The faid Horn or Feeler has no-
thing remarkable in its Texture, but ap-
pears fmooth and tranfparent, without
quot; any of the Afperities that we find on the
Arms of the Fo/j/gt;e. I fhall only add,
quot; that the Gut runs vifible from the'Head
to about of an Inch of the Tail, where
quot; it ends infenfibly, for without a good
Magnifier you cannot difcern its EnJ, but
quot; it feems to be refolved into the Body of
quot; the Worm. The Tip of the Tail is very
tranfparent, and there I faw with great

Delight the Circulation of the Blood in
the Middle, running to the Gut, as it
feemed, and lofing itfelf thereat, by reafon
of its Opacity.—§luœrenda. What is
the Ufe of this Horn or Feeler ? What
Food does the Creature eat ? One would
think nothing taken in by the Horn, f
it be hollow, becaufe the Fsces are fo
grofs : if not, how does it take its Food ?
And what is it in its mature State ? '
The fécond Sort of Animal I difcovered
this Water was about a Line in Length,
having a large Head, with two black Eyes ia
Sockets confiderably projedling, and pretty
long Antenijce. Its Head, Body, and Tail,
Were divided like thofe of the Bee or Wafp
Kind : from the End of the Tail iifued three
long Branches befet with Hairs, and each ap-
peared fomewhat hke the Stem of a Pea-
cock's Feather : they could feparate more
or lefs, be brought together, or move in any
Diredion that fuited the Conveniency of the
Creature. . It had fix Legs, which ferved
either to fwim or creep, with Claws at the
End of each. The Head, Body, and Tail,
Were covered all over with a Sort of Hair or
Down, and under the Tail were a Couple
of moving Parts like Fins, wherewith it
feemed to guide its Courfe in fwimming. It
Was extremely agile.

Plate XIV. N» 7. A. reprefents this
Animal as viewed by the Microfcooe
Vol. II.nbsp;Ynbsp;^ ' The

The Tall Part more enlarged, with its
under Side turned upwards to fhew the Fins,
and its three Branches difplayed, is fhewn at
the Letter B.

The third Sort of Animal, whofe Figure
may be feen in the fame Plate at M, had an
odd Head, flattifh before, without any Ap-
pearance of Eyes; a Body fomewhat opake,.
and a Tail that could divide occafionally.
From about the Middle of the Body a very
thin Membrane was extended, on each Side,
as low as the upper Part of the Gleft in the
Tail; this was moveable, very tranfparent,
and fbrved as a Fin in fwimming. It was
very minute, and fwam along with a direct
Drogreffive Motion, very fmooth and regu-
ar, but not faft. Sometimes it would change
its Figure, and appear fomewhat crooked and
triangular, in the Manner fhewn at N.

IN the Month of July 1745, three Phials
full of Water were fent to me from
Tarmouth, by Mr. Jofeph Greenleafe, having
in them feveral Kinds of Animalcules un-
known to me before. Some of the larger
Kinds died in their Paftage, occafioned I
fuppofe by the Jolts they received, and a

Deficiency of Air; the Phials being corked
clofe, and too full of Water to leave them
Air enough for Refpiration. One kind, how-
ever, fuifered very little, but when examin-
ed by the Microfcope was perfeftly alive
and vigorous, and fo numerous in one of
the Phials, that the Water might be perceiv-
ed to fwarm with them, though their Size
Was much too fmall for the naked Eye to
diftinguifh otherwife than as moving Points.
They all died with me in two or three Days,
but in that Time I had Opportunities enough
^ examine them, very carefully, and take a
Drawing of them. My Friend, Mr. Arderon
oiNorwich, fent me alfo, towards the End of
the fame Summer, fome little Account, with
a Drawing of the fame Animalcule, of which
he had accidentally difcovered a fingle one
in a Drop of Water.

Fig. 27. reprefents this very fingular mi-
nute Water Animal, as it is feen before the
Microfcope. Its Form feems exaftly globu-
W, having no Appearance of either Head,
Tail, or Fins. It moves in all Direftions,
torwards or backwards, up or down, either
rolling over and over like a Bowl, fpinning
horizontally like a Top, or gliding along
fmoothly without turning itfelf at all. Some-
times its Motions are flow, at other Times
very fwift: and when it pleafes, it can turn
round (as it were upon an Axis) very nimbly
Without removing out of its Place. Its
y anbsp;whole

whole Body is tranfparent, except wherff
the circular black Spots are fhewn in the
Piaure; of which Spots fome had fix or
feven, fome one, two, three, four, or five, and
others none at all. Thefe probably are its
Eggs or young ones : but the fhort Time
they were with me, prevented my coming
to a Certainty as to this Particular. The
Surface of the whole Body appeared in fome
as if all over dotted with little Points, and
in others as if granulated like Shagreen : but
their more general Appearance was, as if
befet thinly round with Ihort moveable Hairs
or Brifi:Ies3 and 'tis not improbable all
their Motions may be produced by fome
fuch Inftruments, performing the Office of
Fins.

The Group of Figures, Plate XIII.
Nquot; I. A reprefents the magnified
Appearance of a Congeries of the Spawn or
Eggs laid by a Water Snail: which Con-
geries of Eggs, as feen by the naked Eye, is
Ihewn at the Letter B.

The Parent Snail is exhibited of its natural
Bignefs, C i j its Back upwards toward the

Eye, and its Body extended beyond the Shell,
in the Adion of creeping: from Place to
Place.

The fmall Snail is turned upon its Back,
C 2 J that the true Form and Opening of
the Shell may the better be underftood.

I have frequently kept Numbers of thefe
Snails, for many Months together, in a large
Glafs Jar, with^ Polypes and other Water
Animals : and 'tis very common for them to
faften their Spawn, in little Mafl'es, againft
the Sides of the Glafs, where the Eggs
hatch in about three Weeks or a Month's
Time.

The Spawn, when firft depofited, ap-
pears to the naked Eye like a tranfparent
Jelly; but if examined by the Microfcope,
one fees in it Numbers of fmall and ex-
ceedingly pellucid oval Bodies, at little Dif-
tances from one another, enveloped in a ge-
latinous Subftance; having each of them
towards one of its Extremities a very mi-
nute dark Speck, wherein, if carefully exa-
mined by the greateft Magnifier, a Pulfation
may be difcerned.

This Speck will be found to grow larger
from Day to Day, and to become a perfed
Snail, with its Shell compleat, feveral Days
before it burfts through its Integuments.
When the Eggs are about a Week old, the
Embrio Snail may be difcerned in its true
Shape, turning itfelf very frequently within
the fine Fluid in which it lies: and the Heart

is then a moft agreeable and amazing Spe6ta-
cle, fhewing itfelf very diflindlly, and re-
fembling a little oblong Bladder, much lefs
at one End than the other : the Pulfation
proceeds under the Eye with great Exadtnefs
and Regularity, and the Syftole and Diaftole
of this Veilel are nearly equal to thofe of
the human Heart, fomewhat more than fix-
ty Piilfations being performed in a Minute,
as I have found by feveral Trials, keeping
my Finger at the fame Time on my own
Pulfe, which ufually beats two or three
Strokes more. The Heart is large in Pro-
portion, and inay be always feen, until the
Animal increafmg in Bulk and becoming
confequently m.ore opake, in fome Pofitions
it hardly can be perceived : but as the Ani-
mal frequently turns itfelf within the Egg,
a little Patience will bring the Heart in full
View again ; and that as long as the Embrio
continues within the Egg. Nay, even after
it is hatched, the Heart may be difcovered
for fome days through the tranfparent
Shell

The general Plan of Nature is fo uniform,
in the Produdion of living Animals, though
with fome little Variations as to the Man-
ner of its Execution, that from what we are
able to difcover in the very tranfparent Eggs

of this httle Creature, fome reafonable Con-
jedure may be formed of what happens m
thofe of much larger Kinds.

According to the ufual Order of Nature,
every Emhrio of an Animal is lodged for a
Time within the Vterus of the Parent, in-
clofed in a Cafe or Egg, whofe outer Coat is
either hard and fhelly, or tough and mem-
branaceous, affording a proper Bed and Co-
verino- to preferve it from external Injury.

Int^nimals that are oviparous, this Egg
is excluded out of the Body of the Parent,
fome confiderable Time before the Embrio
has attained a Size and Strength fufficient to
endure being expofed to the open Air with-
out Prejudice : during which Time, it takes
in Nourifhment, and its Limbs acquire a
continual Growth, from proper Juices m
which it floats, and wherewith the Egg is
replete. For the Egg, between the Time of
its being laid, and that of its hatching, can
receive no other Benefit from the Parent,
than what the natural Heat of her Body can
afford it: And Experience teaches that the
like Degree of Heat, fupplied by any other
Means, with the fame Confliancy, will be ot

On the contrary, in viviparous Animals^,
the Egg is retained in the Uterus o£ the Pa*-

• In the Eggs of numberlefs Species, which fhew no
Concern for them after they are once laid, no more Heat at
all is neceffary, than what is common to the Air or Water
in which they are expofed.

rent, till the Embrio having attained a cer-
tain State of xMaturity, endures Confinement
no longer, burfts open the Integument, Cafe,
0r_ Shell that inclofed it, and ilfues there-
with from the Body of the Parent : until
which Time the Einbrio receives itsNourifh-
mentfrom the Blood and Juices of the Pa-
rent, which are conveyed into the Body of
the Embrio, by certain Velfels of the Parent
that inofculate with correfpondent Veflels of
the Embrio, and at the Birth become fepa-
j-ated therefrom.

Hence it appears probable, that the origi-
nal Principle of Li!e, the gradual Expanfion
and unfolding of the Members, and the
Progrelfjon towards Maturity and Birth, are
nearly the fam.e, whether the Embrio be
hatched within the Body or without the Bo-
dy_ of its Parent; which feems to be the
chief Difference between viviparous and ovi-
parous Produdion. But to proceed.

For fome Days after the Water Snail has
laid its tranfparent Egg, the Microfcopic
Spsck of Life, wherein the tender Limbs and
Rudiments of the Animal are moft wonder-
fully folded up and contained, has no other
Appearance of Life than only a languid
Pulfation, but juft difcernible by the beft
Glalfes and the moft- curious Eye. As this
Speck increafes in Bignefs, it exhibits, gra-
dually, the Figure of a minute Snail, and
acquires an /Vbility of moving itfelf very

flowly. After this, its Size and Motion be-
comes every Day more confpicuous, its fpi-
ral Revolutions fhew themfelves more dif-
tindly, its Form becomes more perfect, a
Shell, unconceivably delicate, is produced
.over its tender Body : it now occupies a con-
fiderable Part of the Egg, turns itfelf vigo-
roufly, and even creeps within it, and in due
Time breaks it, and ilfues forth.

'Tis not unlikely this is Nature's conftant
and regular Courfe in the Production of all
Creatures that are oviparous-, and that ftie
proceeds nearly in the fame Manner to pro-
mote the Growth and Birth of the Embrio
in the Human Race, as well as in all other
Creatures that we term viviparous, feems to
me no lefs probable.

After this Digreflion, which I was infen-
fibly led into, I return to take Notice, that
the Eggs which the Drawing exhibits were
about a Fortnight old; at which Time the
young Snails were of fuch Size, in Propor-
tion to the whole Room contained within
the Eggs, as thofe marked c, c, c, may pret-
ty nearly ftiew.

The other aquatic Animalcules reprefent-
ed as hanging about this Parcel of Eggs, are
no other than what were really found adher-
ing to it when it was viewed by the Micro-
fcope : and they were exadlly fituated as in
the Pidture, which was taken without the
leaft Exaggeration. Their extreme Minute-

nefs rendered them abfolutely invifible to the
Eye, for which Reafon no Attempt is made to
fhew them at the Figure B.

A little Colony of Bell-Animals appear at
d: their long Tails are faftened to the gelati-
nous Subftance wherein the Eggs are laid;
they ftretch themfelves out, and play vigo..
roufly in the Water; numberlefs Fibrillas
round the Mouth of each Bell agitating the
Water to a confiderable Diftance.

More of the fame Bell-Animals are feen
at e, curling their Tails in the Manner of a
Screw, and pulling themfelves back with a
fudden Jerk, as they conftantly do when dif-
compofed by any Thing. But when all is
quiet they flowly extend again in the Wa-
ter, as far as their Tails permit.--Thefe

Bell-Animals are found very frequently ad.-,
hering to little Bits of Stick, Leaves, Stones,
.or otfcr Matter that have lain fome Time in
ftagnant Water, either in the Ditches abroad,
•or in Glafles kept in the Houfe with Infu-
iions or Water-Animals : and their Motions
•are very entertaining Many of them are
fometimes feen adhering by' their Tails
to one another.

On both Sides .this Parcel of Snails Eggs
•arefhewn, in different Attitudes, feveral lit-:
tie Creatures, of a Kmd which I have been
ufed to call the Funnel-Anim.al. They faften
by their Tails to whatever comes in their

Funnel'Animals.nbsp;33?
Way, and then opening their anterior End,
exhibit a wide Mouth fomewhat of a Funnel
Form, though not compleatly round, but
having a Sort of Slit or Gap that interrupts
the Circle. The Lips or Edges of this Open-
ing are furnifhed with Multitudes of little
Fibrillse, which by their brilk and continual
Motions excite a Current of Water, bring-
ing with it Abundance of minute Particles of
Matter and living Animalcules, which they
fwallow greedily.—One of them in the Pof-
ture above defcribed may be feen at the Let-
ter/._They can fafhion this Mouth or

If any Thing touches or approaches very
near them, they fhrink back and contrad,

Thefe Funnel-Animals never keep toge-
ther in Cluflers, but live feparately and in-
dependent of one another, fwimming freely
through the Water, feemingly in fearch of
Prey, and after a while fix themfelves to
any Thing they meet with.

Mr. De Reaumur and Mr. Trembley dif-
tinguifh the little Creatures I have been de-
fcribing by the Name oi¹ Tumiel-like Polypi:
and the lafl-mentioned Gentleman, to whofe

1nbsp; I harequot; not the leaft Objeftion to this Name, though I
here retain what I had given them myfelf long before either
of thefe Gentlemen had publiftied theirs: and I am pleafed
to find our Ideas of this Creature fo near alike. ,

indefatigable Induftry we are fo greatly
obliged for many curious Difcoveries of fe-
veral Kinds of what he calls Polypi, has, by
the Help of an ingenious « Contrivance to
•fix the Magnifiers of his Microfcope clofe
to the Glafs Velfels where he keeps thefe
Creatures, found Means to obferve the very
extraordinary Manner of their Increafe;
which I ihall take the Liberty to prefent the
Reader, from the Account given by himfelf
to the Royal Society, and printed in the Phi-
lofophical TrattfaBions, N° 474.

quot; Thefe Tunnel-like Polypi do alfo mul-
tiply by dividing themfelves into two, but
they divide themfelves otherwife than the
Clufiering Polypi; they neither divide lon-
gitudmajly, nor tranfverfely, but floping
and diagonal-wife. Of two Tunnel-like
Polypi, jufl: produced by the Divifion of
quot; one, the firfl has the old Head, and a new
quot; pofterior End; and the other the old po-
flerior End, with a new Head.
quot; I fliall call that which has the old Head
Superior Polypus-, and that which has
the new Head, the Inferior one.
quot; The firfl: Particulars oblervable in a
Tunnel-like Polypus that is going to divide,
are the Lips of the Inferior Polypus-, I mean
thofe tranfparent Edges that are fo con-

by Mr. Trembly N» 484. of ihe Phil. TranJ. ; and a Figure
explanatory of rij^e may be feen Tab. if,. 4, beifng.

fpicuous in the Polypi when entirely-
formed. Thefe new Lips firft difcover
themfelves upon the Polypus that is go-
ing to divide, from a little below the old
Lips, to about two thirds of the Length
of the Polypus, reckoning from the Head :
but thefe new Lips are not difpofed in a
ftrrait Line, according to the Length of
the Polypus, but run floping near half
Way roimd about. Thefe Lips are known
by the Motion in them, but which Motion
is at firft very flow. That Portion of the
Body of the Polypus, that is bounded
by thefe new Lips, then gathers up it-
felf : the new Lips infenfibly draw toge-
ther and clofe; whereby there forms
itfelf, at the Side of the Polypus, a Swell-
ing, that is foon found to be the Head
of the new one, bounded by the new
Lips firft difcovered. Before this Swell-
ing is grown very remarkable, one begins
to diftinguifli the two Polypi which are
forming themfelves; and when that Swell-
ing is confiderably increafed, the two Po-
lypi will be difcovered, no longer joined
but by a fmall Portion to each other. The
Superior Polypus no longer adheres to the
Inferior one, but by its pofterior Extremi-
ty, which is ftill fixed on one Side of the
Inferior Polypus: the Superior Polypus
then begins to make Motions that feem-;
ingly tend to the feparating of him from

quot; the other; and in a little Time he becomes
quite detached, fwims away, and fixes
quot; himfelf elfewhere.—I have feen one come
and fix at the Side of the Inferior Polypus,
quot; from which he was jufl before feparated.
The Inferior Polypus remains fixed in the
fame Place, where the Polypus was, that
is now divided, and of which he was only
«' the half, before the Divifion took place.quot;

The little oval Bodies at h, were invelop-
ed in the flimy Matter of the Snail's Eggs :
they appeared fomewhat opake, but without
Motion, and were probably the Aurelice of
fome Water Infeds.

Before the Reader enters on this
Chapter, let me advife him to caffc his
Eye with a little Attention on Plate XIII.

4, 6, 10, and 13, which will prepare him
to underfland more perfedlly the Account
of what are here termed the Clußering Po-
lypes, a Name 1 call thefe little Creatures by,
in Conformity to Mr. De Reaumur and Mr.
trembley, who have given that Appellation to
all the different Kinds of Animalcules that
are found hanging together in the Water,
after the like Manner.

During all the Spring and Summer Sea-
fons, but efpecially in the Months of April
and May, great Abundance of thefe, of dif-
ferent Species, are to be found on the Shells
or Eggs of Water Snails, on the Leaves of
Duckweed and other Water-Plants, on little
floating Sticks, Straws, or whatever elfe lie
upon or near the Surface of fl:agnant Ditches
or Ponds, for they don't chufe to be at; any
great Depth in Water. The Reafon they
have been but lately and fo little taken No-
tice of, is, I apprehend, their extreme Mi-
nutenefs, which renders them inviflble, un-
lefs by a very good Light, and with Glafles
that magnify confiderably : at the fame Time
an Area, fuflicient to take in their_ whole
Groups or Branches, mufl: come in View, or
elfe no Idea can be formed of them; and
we know, 'tis not many Years, that Micro-
fcopes have been fo far improved, as to com-
m.and a large and well illuminated Area by
Glafles that magnify much, or to have pro-
per Conveniences for examining Objeds
even in a fingle Drop of Water.

Through all the difl'erent Species of this
Kind of Animal, there is an Analogy or Uni-
formity, as to the general Figure of their
Clufliers or Colonies. Each Colony feems
confliantly to arife from one Stem or Stalk,
which is always aflixt to fome extraneous
Body : This Stem divides into a Couple of
fmaller ones, each of which fubdivides in-

to another Pair, and thofe branch themfelvei
out again, in the fame Manner, till the Cluf-
ter is compleated. The Extremities or
Heads of the fmall Stalks are the Bodies of
the Animals, in the Differences of whofe
Figure confifls the Variety of the Species.
Being fituated in this Order round the com-
mon Stematdifferent Heights and Diftances,
they make a very pretty Appearance, when
extended in the Water j not ill refembling a
Nofegay of Cowflips, or fome fuch Kind of
Flowers. And one would imagine the feve-
ral Heads and their Pedicles to proceed from
one common Stem, as the Branchesand
Flowers of a Plant do from one common
Trunk J but a contrary Progreflion takes
place here : for in a Plant the Trunk pro-
duces Branches, and thofe Branches again
produce Flowers; whereas the Head here is
prior to the Pedicle, and the Pedicle to the
main Stem, as will by and by be fhewn.

The Heads, or little Animals, (of which
Mvfttitudes fometimes are dependent from
one Stem,) open their anterior Ends, and
play about very brifkly in the Water, as far
as their refpedive Pedicles will permit; but
every now and then, one or other of them
fprings back with a fudden Contradfion,
which probably may be when it has catched
fomething that it retires to eat: for this
they do when nothing at all offends them ;
but if they are made uneafy, by ftiaking the

Water, or touching them with any foreign
Body, both Stem and Branches inftantly con-.
tradt together, and extend not again till
every thing is perfedly at reft. -

But though they are found thus conjoined
in Colonies, each Head is a perfed Animal,
and can detach itfelf froni the reft, live fe-
parately, and become the Parent of a new
Colony, as moft of them do after a certain
Time. All of the fame Community ad af-
ter one common Law, in contrading or ex-
tending the main Stem as well as itheir re-
fpedive Pedicles at the fame Time, though
each can contrad or ftretch itfelf out at
Pleafure, without the Concurrence of the
reft, as far as the Extent of its own Pedicle.
When a whole Colony contrads together,
the main Stem feems to pull back the feve-
ral Pedicles, and thofe Pedicles the Httle
Animals at their Extremities : but here the
Truth is contrary to the Appearance, for the
Animals themfelves begin the Motion that
pulls them back, by a fudden Endeavour to
draw up their Pedicles to their Bodies, which
Motion the Pedicles communicate to the
main Stem, and thereby contrad that alfo;
fomewhat in the Manner of a Hair, which
jerked fuddenly (not to break) and then let
go again, flies back with an elaftic Force,
And that the Cafe is thus feems pretty cer-
tain, becaufe after one of thefe Animals
breaks off from its Pedicle, and leaves the
Vol. n.nbsp;Znbsp;Colony,

Colony, the deferted Pedicle becomes im-
mediately deftitute of Motion ; and when all
of them are gone (as often happens) the
Stem and Pedicles, though ftill adhering as
they did before, are unable to move at all.

The main Stem grows large in Proportion
to the Number of its Branches, which fome-
times are very numerous; fo that it is pro-
bably a Continuation of all the Tails or Pe-
dicles of the little Animals conjoined toge-
ther. The Stem and Pedicles look ufually
very tranfparent, and like hollow'Tubes.

The feveral Species of thefe Polypes are
nearly alike as to the above Particulars, and
differ chiefly in the Length and Size of their
little Bodies, and the Apparatus wherewith

I have any Knowledge of, no Sort is more
common than that reprefented at N° vi.
When the little Animals of this Species
ftretch themfelves out and open their an-
terior Ends, each of them appears of a Bell-
faftiioned Figure, with a Kind of Lip turn-
ing itfelf outwards round the Rim of the
Bell, which Lip is furniftied with Num-
bers of Fibriilce that vibrate nimbly in the
Water, and caufe a Vortex reaching to a
furprizing Diftance, in Proportion to the
Smahnefs of the Animal : which Vortex is

are lodged together on a Snail, Leaf, or
otiier Body, they feeni of a whitifli Colour

to the naked Eye, but before the Microfcope
they appear very tranfparent, tho'with fome-
what of a brownifli Caft. Their Tails when
contradled are drawn back and difpofed in
fpiral Lines, like thofe of the Bell-Animal^
defcribed 330.

The Species whofe Figure is given N° iv.
is much more uncommon.—Its main Stem
and Branches refemble the foregoing, and
fo does the general Figure of its Body, but
its Mouth is remarkably different, for in-
ftead of the very fmall Fibrillce of the 1 aft-
mentioned Species, the Head of this is fur-
niftied with two large Arms, by the vigorous
Motions of which backwards and forwards,
a Stream of Water is made to pafs by its
Mouth, whereby the Creature is enabled to
fupply itfelf with Food, which is taken in
between thefe two Arms. And indeed it is
amufmg enough to obferve the Behaviour
and Artifice of this little Creature upon the
Occafion j for as foon as the Prey is fwal-
lowed down it inftantly retires to the main
Stem, bquot; trading its Pedicle: and by flat-
ten- :o Body, and bringing the Sides near-
ly .ogether, it prevents any Poflibility of the
Prey's Efcape. After it has continued thus
contra6ted for fome Time, it extends itfelf
very leifurelv, not unlike thj izell-Animal:
but in our prefent Subjed the Pedicle or
Tail when contraded feems as if it was
ihrivelled up, whereas in that it falls back in

fpiral Lines. The Figures of thefe Animal-
cules when playing in the Water are (hewn
2 2 : and it is very common, in this and every
other Kind of the Cluflering Polypes, for the
little Animals either to detach themfelves ¹,
or be broken off by fome Violence from their
Pedicles ; the Appearance of fuch deferted
Pedicles, which have no longer any Motion
or Ufe, is' reprefented 3 3 ; and their Ap-
pearance is much the fame in every other
Species.

A fingle Animalcule with its two remark-
able Arms is fliewn, greatly enlarged, at Nquot;
v. The Diameter of its Superficies next the
Eye being magnified about 400 Times, and
confequently the whole fuperficial Area of
one cf its Sides (which is all the Eye can
command at once) 160000Times; accord-
ing to which Calculation its Bulk would be
magnified 64000000 Times.

Thofe Animalcules of the fame Species,
hanging by their Pedicles, N° vii. are mag-
nified in their Diameter about 40 Times,
1600 Times in their Superficies next the Eye,
and in their Bulk 64000 Times.—All the
other Species of Clujlering Polypes expreflTed
in this Plate are magnified nearly in the fame

1nbsp; When an Animalcule ia feparated from its duller, it
fwimG about in the Water, until it faftens its little Pedicle to
fomewhat; and it can detach itfelf again and feek fome other
Situation fo long as it continues fingle ; but after it begins to
inultiply, the Pedicle 'never loofer.s itfelf again, none but
iingle Animalcules being ever feen fwimming.

Proportion, whereby the Reader may form
fome Conception of their Minutenefs: and
yet, fmall as they are, they are Whales in
Proportion to the Animalcules they fwallow
down.

N° X. reprefents a Colony of another Spe-
cies of Clujiering Polypes, two fmgle ones of
which magnified in the above Manner are
Ihewn N° xi. and Nquot; xii.

Thefe when extended in the Water ex-
hibit a Couple of projecting Parts at their
anterior End, furnilhed with Numbers of
vibrating F/^r/Z/^g', that produce a Current of
Water by their quick Motions, and thereby
procure them Food. See N° xii.—There are
fome with three of the like Projections, See.
See N° XI.

N° XIII. fhews a very extraordinary Spe-
cies of this Kind of Animalcule, the Body
whereof is much longer, its Pedicle fhorter,
and the Connexion of the Individuals to each
other in the fame Colony is very different
from all the reft; for here no main Stem is
feen, but all the Pedicles are joined in one
Center, round which the little Animals ex-
tend themfelves circularly, at nearly equal
Diftances, and make a very pretty Appear-
ance. But nothing relating to them is more
Worthy.Notice, than the curious and wonder-
ful Apparatus whereby they take their Prey,
which the two greatly magnified Figures at
N' XIV. will affift the Reader to underftand
the following brief Defcription of.

The Body of this Animal is very tranfpa-
rent, feems to be hollowand fomewhat flielly,
and is in Diameter at the broadeft Part (which
is about the Middle Way between its Mouth
and Tail) nearly one fifth of its Length : it
leflens from thence towards both Extremi-
ties, tapering pretty fuddenly towards the
Tail End, and terminating in a long flender
Tube near a Quarter of the Animal's Length.
Towards the Mouth End it diminiflies more
gradually, and not fo much, being no where
lefs than one Half of its greatefl; Diameter :
it widens again a little about the Mouth,
which is quite open like that of a Jug or
Pitcher, and feems not capable ofContradion
or Dilatation, or furniflied with any Wheels
or Fibrille, as the Mouths of the other Spe-
cies of the Animalcules are : but to make
amends for fuch Deficiency, it is provided
with a moveable Operculum or Cover, con-
neded to its Body by a long Ligament
or Mufcle, which extending dov^^nwards
(through the Body or Shell) is afiixed with-

Ligament is fufiiciently long to permit the
Operculum to be lifted up to fome Diftance
from the Mouth, in which Situation üx Ft-
brillce appear placed round the Border of the
Operculum, atDiftances nearly to^vLzl.fVid.b.J
Thefe Fibrillen have a vibrating Motion lik®
thofe at the Mouths of the other Clußering
Polypes, and ferve by the Current they ex-
cite

cite in the Water to hurry the Prey into the
Mouth of the Animal, which ftands open to
receive it; then by fliutting' the Operculum
down immediately all Efcape is prevented.
After a little while the Operculum is lifted up
again leifurely, and in Readinefs for another
Capture.

When the Operculum is drawn down the
Fibrillin are- no longer difcoverable, and the
Ligament whereby the opening and fliutting
is performed' appears in a flaccid relaxed
State, as at a.

One of the two magnified Figures in the
Plate reprefents the Animal with its Mouth
open and the Cover up, as it appears when
huno-ry j the other fhews the Cover drawn
down after it has feized its Prey

Having defcribed thefe feveral Sorts of
Cluftering Polypes, (and I make no Doubt
there are many other Species and Varieties
of them unknown to us at prefent) I proceed
to confider their prodigious and fpeedy Pro-
pagation and Increafe, the Manner whereof
is no lefs furprizing than all the other Par-
ticulars relating to them : and as to this Af-
fair (though I have obferved them many
Times myfelf with much Attention) I fhall
.chufe to lay before the Reader what Difco-

* I never had been fo lucky myfelf as to meet with this
gpecies of Water Animals, but am obliged to Mr. Arderon,
(on whofe Judgment and Fidelity I can depend intirely) for
^he Figures and Account thereof.

varies the uncommon Diligence and Sagaci-
ty of Mr. Trembley, who has applied himfelf
more than any body to this Enquiry, has
been able to produce : for in fuch extraor-
dinary Cafes 'tis neceffary to make ufe of all
the Evidence one can.

quot; A fmgle Polypus (fays he) detached
from the Clufler, fwims about the Water,
quot; till it meets with fome proper Body to
fix itfelf upon. It then has a Pedicle, but
which is not longer than the Polypus it-
felf. In the Space of 24 Hours this Stem
quot; becomes eight or nine Times as long as
quot; it was at firft; and it is this Pedicle which
quot; is to become the main Stem of the new
Clufler.

quot; After this the Polypus multiplies, that
is to fay, it divides and fplits itfelf in-
to two length wife.—One firft obferves
the Lips to be drawn into the Body, whofe
anterior Part clofes and becomes round :
quot; the anterior Part of the Polypus flats itfelf
afterwards by Degrees, and fpreads in Pro-
quot; portion, becoming broader as it fhortens ;
quot; it then gradually fplits down through the
quot; Middle, that is, from the Middle of the
Head to the Place where the pofterior
quot; Ends join to the Pedicle: fo that in a little
while, there appear two feparate round
Bodies joined to the Extremity of the Pe-
quot; dicle that juft before fupported but: one.
'' The anterior Part of each of thefe Bo-

dies then opens by Degrees, and as they
open, the Lips of the new Polypi fhew
themfelves more and more; and, foon
after the Separation is compleated, each
begins to Ihew a Pedicle of its own.«——
Ten or twelve Hours after, thefe two
Polypi again divide themfelves each into
two more ; they foon after put out
Branches, and thus retire to a greater
Diftance from each other.—When two
Polypi are thus formed by the Divifion of
one, the one is ordinarily much larger
than the other : this larger one remains
at the Extremity of the Branch where it
was, but which Branch lengthens itfelf
more, whilft the other puts out a new
Branch which feems to proceed from the
firft. The larger of thefe Polypi again
divides itfelf generally before the other:
and all I have been defcribing is reiterated
feveral Times. Thus a principal Branch
is formed, provided with feveral lateral
ones: thefe lateral Branches become
principal, with regard to thofe which in
their Turn feem to fpring from them, when
the Polypi at their Extremities come to
divide. — All the Polypi of a Clufter do
not detach themfelves from it at the fame
Time : thofe which are neareft to the
Origin of the Branches ufually detach
themfelves firft. And every Polypus fo
detached, goes and fixes itfelf elfewhere;

c«
*t
t(

tc
lt;c

fC
lt;t
tc

lt;(
((
t(
lt;f
*f
tc
ec
tc
te
te
ee
te
te
lt;e
te
tc
tc
ee
t(
te
I e
tc
ft

quot; eyery one thus becoming at laft, if not
prevented, the Principal of a new^Clufter.
Mr. Trembley tells us farther, quot; that he
followed the Progrefs of a Clufter in the
quot; Month of September 1744* It confifted,
on the 9th Day of that Month, but of one
fingle Polypus ; this Polypus divided itfelf
that Evening, and at Half an Hour after
Eight of the Clock, there were to bedifco-
vered two perfed Polypi, whofe Pedicles
or Branches continued lengthening till
the Morning of the next Day, being the
** Tenth of the fame Month of September..'
quot; At about a Quarter after Nine that Morn-
ing, thefe two Polypi began alfo each to
quot; divide, fo that after a Quarter paft Eleven
quot; there were four compleat Polypi, whofe
quot; feveral Pedicles formed themfelves foon
quot; after. On the Eleventh of the fame Sep-
tember, about Half an Hour after Seven in
quot; the Morning, he f;)und that thefe four laft
quot; Polypi had already again divided them-
quot; felves, that is to fay, there were eight
«« diftindl Polypi.—And he has taken No-
tice of Clufters, the Numbers of whofe
Polypi have conftantly gone on doubling,
from 2 to 4, from 4 to 8, from 8 to 16,
from 16 to 32 : after which he has been
quot; no longer able to count exactly the Num-
quot; her of the Polypi.quot;—But their Multipli-
cation is fo prodigious, that he fays, quot; on
November I ft., 1744, there was in one of
quot; his Glailes, a Clufter compofed of feveral

lefier united Clufters, which was abjvc ,
an Inch oyer every Way.quot;
Thefe Quotations are taken partly from
Nquot; 474 of the Phil. Tranf. and partly from
the Appendix to the 44th Vol. of the faic^ ,
TranfaBions. The Polypes here particularly
intended, are thofe I have called Bell-Ani-
mals in the former Part of this Work, and
that Species whofe Figure is given in this
Plate N° vi. and its Defcription, page 338.
There is however Reafon to believe, that
all the other Clufiering Polypes already taken
Notice of in this Plate, may be propagated
after the fame Manner.

Nquot; VII. VIII. IX. ftiew different Appear-
ances of the fame Animalcule, which is ano-
ther Species of Funnel-Animal, vid. N'l.
fg. They are found together fometimes in
vaft Abundance on the Shells of Water
Snails, feeming to the naked Eye like a
green flimy Matter. When firft applied to
the Microfcope, they are ufually feen con-
traded, as Nquot; VIII. but being left at Quiet
for a little while, they change their Figure
to that of N' VII. and fwim about very
briflcly with their large Ends forward. At
other Times they appear like N° ix. having
then a toothed Wheel at the Head or largeft
End, that moves round with prodigious Ve-
locity, in the Manner of the Wheels of the
Wheel-Animal, already defcribed page 269,
l)ut having a much larger Wheel than eithe^

of thofe the Wheel Animal is furnifhed with.
Its Gyrations are fo fwift, that without great
Attention they cannot be feen. The Teeth
are moft confpicuous when it begins or ends
its whirli or when it becomes fick by
Confinemeni :, - Drop of Water. On be-
ing difturbed by any thing, they contradt
themfelves as at Nquot; viii.

^ HE Figures and Defcription of N'xv.
_ I, 2, 3, were fent me by Mr. Arde^
ron, in March 1745-6.—He fays, that on
the firfl Day of the faid Month he found in
the Water of a Ditch, at Norwich, fome ex-
ceeding ftrange Animalcules, which from
their bearing fome Refemblance to the Fa-
fhion of that Fruit, he calls Mul'erry InfeSls :
tho' the little Protuberances that fland out
round them equally on every Side, make
them rather more globular. Their Bowl-like
Motions are much the fame as thofe of the
Globe Animal, defcribed page 322 ; but they
did not move fo readily from Place to Place,
and their Protuberances appeared folofely
C(5nneded together, he fliould rather take
them for a Congeries of Animalcules than
one fingle Animal.—As to this Particular

he feems however in fome Kind of Doubt:
and in a Letter received from him after-
wards, he imagines the Mulberry InfeEl may
poffibly be the laft-mentioned Clujiering Po-
lypes with Opercula (N° xiii.) not yet come
to their perfed: State. He met with feveral
of thefe Infeds, or Congeries of Infeds, of
different Sizes, and with different Numbers
of Knobs or Protuberances, fome having 50 or
60, others more or lefs, even down to 4 or 5,
but the Manner of moving was the fame in.
all.

U' PON the Sea-ftiore, on the Coaft of
Norfolk, and without Doubt in other
Places, Heaps of fandy Matter are to be feen
at low Water, two or three Feet fometimes
in Length, compofmg Multitudes of fmall
Tubes or Pipes, which are the Cafes or Ha-
bitations of living Creatures. My Norwich
Correfpondent, to whom I ftand obliged for
this Information, wrote me Word, that a
Friend of his broke off and brought to him
a fmall Piece of fuch a Congeries of Tubes
or Pipes, in Shape and Size as at N° 11.,
in which aa aa ftiew the Mouths or Open-
ings of the Pipes wherein the little Creatures
make their Abode.

He carefully feparated one fingle Pipe
from the reft, and placed it in a Glafs of
Water, to give the little Inhabitant an Op-
portunity of coming to the Mouth of its
Cell, which it did accordingly very foon,
and then appeared as at N° in. where the
Figures both of the Animal and its Cafe are
magnified nine or ten Times in Diameter.—.
The Pipe or Cafe b is made of Sand, inter-
mixed here and there with minute Shells
and Sand, all cemented together by a gluti-
nous Slime iffuing I fuppofe from the Ani-
mal's own Body c, which is compofed of
mufcular Ringlets, (like thofe of a Worm,)
capable of great Extenfion or Contraftion.
The anterior End or Head d is exceedingly
beautiful, hiving round it a double Row of
•little Arms, difpofed in very regular Order,
and able I fuppofe to extend themfelves for
the catching of its Prey, and conveying it to
the Mouth that appears in the Middle of this
anterior End. But the Animal being fick
for Want of Salt Water did not extend its
Arms at all, and expiring foon after, no Way
was left of coming at its true Figure when
ftretched out.

I am fenfible that the Account here given
is very imperfefl:; but it may I hope induce
fome curious Body, who lives near the Sea-
Shore, and has an Opportunity of fo doing,
to furniili us with a better.

Wafer Hog-Loufe or SotiJ. 35«
Pipes or Tubes of this Size and Figure
are fometimes found petrified, and conftitute
one Species of the Syringoides.

-IHE Animal figured Plafe XIV. N° i.
although an i^quatic, bears fo near a
Refemblance in its general Appearance to
the Millepedes, Sow or Hog-Loufe, efpeci-
ally when creeping at the Bottom of any
Veflbl wherein it is kept, that it may proper-
ly enough be called a Water Sow, or Water

Its whole Length is made up of nine Di-
vifions, the anterior and pofterior whereof
are the Head and Tail. To the Head, wiuch
is almoft round, and about the Part of the
Animal's Length, are affixed two very long
Anfennœ, each confifting, next the Head, of
four diftind Joints, and then ftiootmg out
a Part extremely flender and tapering, and
but little ftiorter than the whole Body of the
Animal ; which on a clofe Examination ap-
pears compofed of many Articulations, ha-
ving an exceeding fine Briftle ifl'uing from
each, as the larger Joints near the Head
have ; from the Infertion of the fécond of

fifting of one Joint, and a flender tapering
Part articulated and briftled as the above de-
fcribed, but of no great Length. This is
fhewn in the Figures, i, ii, iii. In the
Middle of the anterior Part of the Head are
placed two very fmall and fhort Feelers.
Its Eyes, if it has any (which I think its Ac-
tions leave no room to doubt) are not difco-
verable ; either from their Smallnefs or the
Opakenefs of the Animal.

The Body (not reckoning the Head and
Tail) is compofed of feven iSivifions, which
increafe in their Breadth, but not much in
their Length as they approach towards the
Tail, the Body being about three Times as
broad at the laft of thefe Divifions as it is at
the firft. From the firft Divifion next the
Head arife two fhort Claws, terminated by a
Hook that can bend down like aClafp-Knife,
and from every one of the other Divifions
proceed two long Legs, each compofed of
five Articulations, and alfo a f rpit law at
its End. In thefe Legs two Blood-Veflels
may be difcovered, even by a Glafs that does
not magnify very greatly : one carrying the'
Blood from and the other returning it to the
Body. The Globules of this Blood, or ani-
mal Fluid, appear about ten Times as large as
thofe of the human Blood, and their progref-
five Motion is very flow and languid, where-
by they become more diftinguifhable than
the Globules are in the Blood of Animals

whofe Circulation is fwifter. The Legs are
very hairy, efpecially at the Joints, and fo
is the whole Body of the Animal, which oc-
cafions it to be frequently fo covered and en-
tangled with the Dirt and Scurf of the Wa-
ter, as to prevent its Figure from being tru-
ly feen.

The Divifions of the Body are each of
them covered on- their upper or back Part
with a Scale or Cruft, extending beyond and
hiding the Infertions of the Legs, which
however are fhewn in Nquot; 11, where the Ani-
mal is turned on its Back. To the hinder-
mofl of thefe Divifions the Tail is fixed,
which is perhaps the mofl remarkable Part
of the Animal. Its Length is about three
Times as much as that of the largeft Divifion
of the Body; its Breadth nearly equal to its
Length, but taperijig fuddenly towards the
End, like the Tails of fome of the Beetle
Kinds. From the back Part thereof, which
is covered with a Shell or Crufl, arife two
joined Branches, ftanding out at an Angle
of about 45 Degrees to the Plane they rife
from, each dividing again into two, and hav-
ing Briftles like the Legs. The Ufe of thefe
Branches is not yet difcovered.

On the under or Belly Part are placed two
Sets of Valves, rifing up and falling down,
alternately, in a perpendicular Diredion: thefe
may probably ferve for the Purpofe ofLungs,
or as the moveable Coverings of the Gills of
Vol. II.nbsp;A anbsp;Fifhes,

Fiflies, to breathe through, or regulate fomff
of the other animal Fundtions. And what
feems to confirm this Opinion is, that on de-
priving the Animal of them, the Circulation
in the Legs ceafed inftantly, though the
Creatures lived for fome Time afterwards.
The Motion of the Valves, however uniform
at any one Time, is not always of the fame
Quicknefs, being now and then fo flow as
nearly to beat Seconds, (when it is vifible,
even by the naked Eye, in certain Pofitions
of the Animal) whereas they move at other
Times with above twice that Velocity. And
this feems to be nearly in Proportion to the
Temperature of the Weather, their Motions
.being always floweft in the coldeft Seafons.
At b N° III. which is a Profile View of this
Creature, the Valves are fhewn as they ap-
pear when moving. Their v/orking up and
down continually, renders it diflicult to be
fure of the true Figure, or indeed the true
Number of them; but there feems to be
four Pair, which move not all together but
alternately. The external Pair feems ftrength-
ened and fupported by a Couple of ftrong
jointed Tendons, as is fhewn at Nquot; ii. L

The natural Size of this Animal when at
its full Growth is about three Tenths of an
Inch in Length. Its Motion, notwithftand-
ing the great Number of its Legs, is very
. flow, aukvvard and unwieldy: and indeed the

render them incapable of fupporting the Bo-
dy in the fame Manner as thofe of other Ani-
mals do : fo that it more properly may
be faid to be dragged along by than to be
carried on them. This Kind of Motion
makes him a very difagreeable Companion
to other aquatic Animals that happen to in-
habit the fame Velfel with him, which he
rather chufes to trample on and overturn
than to move out of his Way for them. He
is however as much tormented in his Turn
by Funnel Animals, Bell Animals, Wheel
, Animals, ^c. which frequently faften them-
felves upon him, in fuch a Manner as not to
be difengaged by his utmoft Efforts.

He fwims fometimes, or rather climbs tq
the Top of the Water, by the Help of his
Feet, but cannot remain there for any Length
of Time, his Weight immediately ftnking
him down again,: and indeed he generally
chufes to continue at the Bottom, where he
frequently is found covered and overwhelm-
ed by the flimy Sediment of the Water. He
fometimes alfo brings his Head and Tail to-
gether, and forms himfelf into a Ball in the
Manner of the Land Hog Loufe.

As to the Way of their Generation, no-
thing farther is yet difcovered than that they
are viviparous : for they are fometimes found
having a large Bag hanging dov/n from
their Bellies, as ihewn at a, Nquot; iii. On cut-
ing this open the young ones have been feen

to come out alive, to the Number of fevenfy
or eighty : yet on examining the Animal
the Day following the Operation, there ftill
appeared fome remaining in the Bag) but
whether they came not all out at firft, or
that fome of them returned in again, was un-
certain, tho' the latter feem'd moft probable.
An old one is fometimes feen holding one
of its Young, (when grown even to a con-
fiderable Size) under its Belly between its
Legs, which it will not part with unlefs
compelled to do fo by fome confiderable
Force.

fTAHE Animal whofe Figure is exhibited Nquot;
X iv. P/. XIV. was brought tome,amongft
a Variety of other Infeds, in fome Water
taken out of a Pond communicating with a
Ditch atnbsp;Town, nzzx London. The

Head and Breaft were cruftaceous : the Tail
and Belly Part were foft, and except the In-
teftines extremely tranfparent ; by which
Means, the periftaltic Motion of the Bowels
could be Teen with great Diftinänefs. The
Head was armed with a Pair of ftrong For-
ceps, ferrated or toothed near their Bafe like
thofe of fome Spiders, whereby they are the

quot;better enabled to hold their Prey, A Pair
of hookea Claws were likewife placed near
the Infertion of the Forceps, and became
affifuu^ to them, A Snout projeding be-
tween the Forceps, having two very fhort
Feelers, and between them a lharp flender
Probofcis, could be thruft out or drawn back
at Pleafure. Under the Breaft and Belly
•were fix Legs, ferving either to fwim or
crawl. It had two pretty large black Eyes :
from the Breaft to the Extremity of the Tail
the Sides were thinly befet with Briffles, and
a few Briftles were upon the Legs. The
Bowels were feen moving, as plamly as if
they had been in a tranfparent Cafe, widen-
ing their Diameters and rifing upwards to-
wards the Breaft, and then prefently con-
trading in Width and extending downwards:
thefe Motions were alternate ; and fometimes
the Bowels were fi;retched almoft to the End
of the Tail, where the Anus was placed, and
there difcharged theFseces. It was exceed-
ingly voracious, kdling and devouring moft
of the other Creatures that were in the Wa-
ter with it.

I take this Animal to be a Frefh Water
Squilla, of which there are many Species.
It was about twelve Times lefs than the
Drawing, and therefore muft either be of a
much fmaller Species than I have ever met
with, or elfe a very young one, not yet per-
haps come to its perfed State; the Tail be^

ing neither jointed nor fcaly as the larger
are, fome of which I have feen bigger than
the Figure before the Reader. I know the
Sqiiilla change their Coats feveral Times, and
perhaps they may alfo change their Form. _

As the natural Hiftory of the Squilla is
known to very few, I fhall here infert fome
curious Obfervations made thereon by Mr.
Jofeph Sparßall, of Wells in Norfolk ; in a
Letter dated April 6th 1749.

The following Obfervations (fays he)
were made laft Summer, whilft I lived at
Wymondham, on an Infed very common in
the ftanding Waters thereabouts; I think it's
the fame defcribed by Mouffet in his Theatre
of InfeSls, by the Name of the Squilla Aqua-
tica. — In fearching for other Water In-
feds, I have frequently found thefe amongft
Weeds in Ponds and Ditches, full two In-
ches and a half in Length.

The Head of this Animal is broad, fiat-
tifti, and pretty tranfparent, being very thin
in the fore Parts. It has no Mouth, nor
does it feem to need any, for it takes in all
its Nouriftiment through a large and ftrong
Pair of Forceps, one Limb of which is plac-
ed on each Side its Head. Thefe Forceps are
hollow almoft their whole Length, with a ve-
ry fmall Aperture on their Infide ; and when
the Creature has feized its Prey, the Juices are
conveyed through the Forceps, by two Chan-
nels, to about the Middle of the Head; where

both Branches unite and are thence continued
to theStomach. lam the more certain of their
receiving no Nourifhment but what palfes
through the Forceps, as J have often by the
Affiftance ofi fingle convex Glafs, and fomp-
times by the naked Eye only, when the In-
feft has been fucking its Prey, feen the
Juices thereof pafs in a fine Stream through
the Forceps and Head. This is more parti-
cularly vifible juft after the Squilla has caft
its Skin J at which Time the Forceps and
Head are moft of all tranfparent. Six very
fmall black Eyes are difcernable on each Side
of the Head, very near the Origin of the
Forceps.

Its Body is compofed of eleven Joints or
annular Divifions; the Edges whereof Aide
eafily over one another : the laft Divifion is
long, tapering and hollow, ferving to buoy
up the Animal to the Surface of the Water ;
its Back is hard and of a dark brown Colour,
having a paler Streak down the Middle : its
Belly is foft and yellowifli: it hath fix Legs
finely befet on each Side with a fingle Row
of Hairs; its Tail is alfo hairy and divided
at the End,

In the Water it generally hangs, fufpend-
ed by the Tail, from the Surface ; the Body
arching backwards, fo as to make the Belly
the convex Part, and the Head inclining
upwards towards the Back. In this Pofture
it waits, like its Fellow-deftroyer the Croco-

dile, quite motionlefs, till its Prey is fairly
within its Reach ; when by a fudden Spring
of the Head it feizes it in an Inftant, and
feldom quits it till it has got its Belly full.

I kept feveral of thefe Squilla in Jars dur-
ing the greateft Part of laft Summer, to
make Obfervations on their Manner of feed-
ing ; in order to which, I began with giving
them the larger Sort of Earth-Worms, which
they feized with the greateft Eagernefs ; and
notwithftanding the wreathing and twifting
of the Worms for a long Time, they very
feldom quitted their Plold, till the inward
Contents were quite exhaufted, and nothing
left but the Skin.

I ufed frequently, for Want of more pro-
per Food, to give them fmall Pieces of raw
Veal or Mutton, which at firft they were
very greedy of, but would not eat for above
a Day or two together : but whilft I have
been giving them a Bit of Meat, they would
ftrike at my Fingers with great Fury, though
they were not able to penetrate the Skin*.

One Day I oft^ered one of them a very
large Tadpole, and quickly difcover'd it was
its natural Food by theGreedinefs with which

* One of thefe, which I kept feme Time, was fo bold and
furious as to attack any thing that was put into the Water:
infomuch that I ufed frequently to divert my Friends with
holding a Quill near it, which it would fly at and feizd with
great Violence, and hanging faft thereto by its Forceps, would
iquot;jfter itfelf to be pulled up quite out of the Water by it.

it feized it: and by giving theni in large
Quantities, I found it would fometimes de-
ftroy near twenty of them in a Day, fucking
them till all the Inwards were exhaufted.
Another Time I put a Tench of about three
Inches long into a Glafs of Water, where one
of thefe Creatures was, fcarce believing it
durft make an Attempt on an Animal fo fu-
perior in Size : but no fooner did the Tench
come near the Squilla than he ftruck at it
with all his Might, and fixed his Forceps in
its Side; tho' the Struggling of the Tench
made him quit his Hold. A Drop or two of
Blood ifihed from the Wound, and the Filh
died in about a Minute : which makes it
not improbable, the Bite of this Creature
may be poifonous to the Inhabitants of the
Waters.

The Banfticle itfelf, which is fo great a
Deftroyer of the fmall Fry of Fifli, and fo
well armed for Defence, is notwithftanding a
Prey to this Devourer; as I found by putting
a very large one into the Jar where I kept
a Squilla. This Banfticle had lived about
a Month in a Jar amongft fome Tench, moft
of which had felt the Effbas of his Fury,
though three Times larger than himfeit.
He was always very lively, and would leldoai
fuffer the Tench to meddle with the W oi .ns
I gave them, till his own Belly was fuli. but
on putting him to the Squilla he was chang-
ed immediately from the moft daring to

the mofl fearful Animal; lurking at the Bot-
tom of the Glafs, and continuing there for
feveral Hours together j neither would he
touch the Worms I offered him, feeming
perfedly fenfible of the Power of his Ene-
my. However at laft, coming within the
Reach of the Squilla, it feized him furioufly
by the Back, entering its Forceps on each
Side, and after a few faint Struggles he yield-
ed to the Conqueror.

Some Time after, I put into the fame Jar
two fmall Water Newts, of about an Inch
and a half in Length; which were both de-
voured in a very little while. I alfo put into
the fame Jar a Water Newt near four Inches
in Length, imagining the Squilla would not
venture to attack one of fo large a Size; and
indeed at firft he feemed afraid of it, but in
a few Plours ventured to flrike at it: though
the Skin of its Back being too thick for his
Forceps to enter, he made feveral unfuccefs-
ful Attacks, till feizing it by the Belly he
quickly killed it.

Thefe Creatures certainly deftroy great
Numbers of Fifli, and may poflibly occafion
the Death of many of thofe that are fre-
quently feen lying dead by the Sides of
Ponds, ^c. yet they feem more fond of
Tadpoles, and are found very large and
plump where there is Plenty of the.m ; but in
other Places are generally very fmall.

I have obferved another Species of the
Squilla fomewhat different from the former:
they are conftantly hunting about in queft of
Prey, fwimming by the Affiftance of their
Legs in an horizontal Pofition. I put fe-
veral of both Sorts into a Jar of Water to-
gether, but the firft-defcribed quickly de-
voured all the laft, though fome of them
were nearly of an equal Size

as the Millepes is fmooth, and its having a
pretty long briftly Tail, it infinitely furpalTed
any of that Kind in Beauty. The Coat or
Ground was brown, and on that a great
Number of indented Briftles or Spines were
fet,whichon its Sides were difpofed in Tufts,
but on its Back in Rows. They were of a
ihowy Whitenefs, and made fo fine a Con-
traft to the brown Coat whereon they ftood,
that the whole, when magnified, refembled
a curious Piece of Carving in Lignum Vitas
fet offquot;with Decorations of Ivory.

This is a rare Infed, of which I don't re-
member ever to have met with any Defcrip-
tion.

^^ MONGST fome Water and Weeds
jC \ brought from a Ditch that commu-
nicates with the River Tar, a beautiful little
Animal was difcovered, fMay .()ih. 1746,)
whofe Singularity feems well worth defcrib-
ing: and it is hoped that the Figure N° vr.
will give a pretty good Idea of it. The Head
was remarkable for two very large pearled
Eyes and a Pair of long Antennge. The
anterior Part of its Body had much the Re-
femblance of fome of the Beetle Tribe, and

was furnifhed like them with fix flender
Legs. Immediately below this Part, the
Body leflened, and was connected together
by feven Articulations, the Part between
each Joint fpreading wider at the lower
than at the upper End. They appeared all
together like the Spinal Vertebras ; and from
the Procefs of each Joint iflîied a Pair of
Fins, making feven Pair, or fourteen in
the whole. Three other Joints below the
Fins terminated the Tail, the End whereof
was ornamented with three long and very
elegant Briftles, befet on every Side with
fhort Hairs, and appearing like Plumes of
Feathers. The whole Animal was of a faint
green Colour, except the Fins, which were
as tranfparent as Cryftal. Under each Fin
flood out a fmall Spine ; ferving either to
fupport the Fin, or as a Vi^eapon of Defence.

Its Motion in the Water was extremely
fwift, darting itfelf along at a furprizing
Rate : with one Stroke only of its Fins it
would fwim acrofs a Glafs Jar it was kept
in; but out of the Water it creeped as
Land Infeéls ufually do. Its Legs were never
employed whilft in the Water, and on the
Land it makes no Ufe at all of its Fins.

This Animal is in its Nympha State, out
of which it changes into a fmall Species of

N inquifitive Mind will be inexprelil-
bly delighted with confidering the
different Forms of living Creatures : the
Changes they undergo j their feveral Parts,
Members and Organs; the Manner of their
Produftion; theirvarious Motions, Difpofiti-
ons and Ways of Life; the different Kinds of
Food they eat; their Sagacity, Cunning and
Dexterity in procuring it, and the Inftru-
ments they are furniftied with for thät and
every other needful Purpofe. Thefe are Sub-
jects that open the Underftanding, and unit«
every Faculty of a well difpofed Mind to adore
the Almighty Author of fuch amazing Con-
trivance, Order and Beauty. Every thing
that lives can furnifli out an Entertainment
of this Sort: but the larger Animals with
which we are daily converfant and familiar*
though of a more noble Nature, and imme-
diately neceflary to Man : thefe, I fay, as
to the Particulars abovementioned, have not
the fame Charms of Novelty to gratify Cu-
riofity and recommend them to a ftrict Exa-
mination, as thofe very minute and almoft:
imperceptible Creatures, difcoverable by
Glafles only: with any whereof we are hi-
therto but llenderly acquainted, and of which

there may be probably Thoufands of Species
never feen by an human Eye
• Amongft the fmaller Animals, the little
Creature I am about giving an Account of
has I believe hitherto efcaped Obfervation j
and might perhaps have ftill continued long
unknown, had itnot been difcovered accident-
ally, by the fame ingenious Searcher into Na-
ture, to whom the Reader is obliged for
many curious Articles in this Volume, and
whofe Defcription of it I can depend upon,
though I have not met with it myfelf
In a Letter now lying before me, dated
loth 1746, he writes me Word, that
on the 25th of the Month oiMay preceding,
going to the Seat of Benjamin Nuthal, Efq;
at Framingham, in Norfolk, he had the
Pleafure there of feeing feveral Cafcades,
fupplied with Water from the Side of an
adjacent Hill, and affording a moft charm-
ing Profpeft : and that as he was there at-
tentively obferving one of the Conveyances
belonging to the Cafcades, through which
the Water ran extremely fwift, he difcerned
at its Bottom feveral fmall Infedls, ftanding
eredl upon their Tails, and refembling when
all together the Combs of Bees at the Time
they are filled with their Aureli^ j but on
touching them, they immediately feparated
and difperfed. However he took up many
of them in a Bottle with fome Water, in or-
der to examine them at Leifure; and looking

at them next Morning, he found they had
formed a great many Threads in the Water,^
much refembling the Webs of Spiders: one
of them being taken out of the Battle with
a Quill, it dropped therefrom, and fpun a
Thread by which it hung, exaftly like the
common Garden Spider.

He then examined one of thefe Creatures
by a Microfcope, and was much furprized at
the Oddnefs of its Shape, and the very ex-
traordinary Method whereby it takes its

elegantly turned with a Lathe; being curi-
oufly rounded, and gradually fwelling and
diminifhing in feveral Places; and at the Tail
End were three Spines whereon to raife it-
felf and ftand upright in the Water; but the
moft amazing Circumftance of all was the
Apparatus about its Head, where there was
placed on each Side a Kind of Fan or Net-
like Machine, ferving to provide its Food.
Vid. Wyiw. PlateXlN.

the Animal whatever was taken in them
proper for its Food. When the Creature
did not employ its Nets, it thruft out a Fair
of fharp-pointed Horns for its Defence, as
is ftiewn at N° ix, where a larger Figure of
the Head and Claws is given, the Diameter
being there magnified twenty Times, and the
Area 400.

Thefe curious Animals were all dead in
48 Hours, notwithftanding frefti Water was
given them feveral Times ; which then pre-
vented any Opportunity of learning more
concerning them, and made my Friend ima-
gine they might be amphibious Creatures,
tho' he found them in Water j or might pof-
fibly undergo fome Change in Form, or Way
of living, the Difcovery whereof he hoped
for at fome other Seafon.

He fearched for them after this in the
fame Place feveral Times, but without be-
ing able to find any of them, which occa-
fioned him to conclude, they had either put
on another Form, or removed themfelves to
fome other Parts of the Water. However
he had met with no Opportunity of looking
there for them, at or about the Seafon when
he had firft obferved them, 'till the Year
1749, when happening to be near the Caf-
cades on the 21ft of May, he determined to
try his Luck once more, and then found,
with little Trouble, many of the very fame
Animals, in the moft rapid Part of the Caf-

370 InfeSi with Net-like Arms.
cade where he had feen them firft. He
carried feveral of them home very carefully
in a Phial, but in two Days moil: of them
were dead, and the reft having fpun them-
felves thin tranfparent Cafes, (which were
fattened either to the Sides of the Glafs, or
to Pieces of Grafs put into the Phial with
the Water,) became changed into what he
fuppofes a Kind of Chryfalis, of which a
Front-View is given Nquot; xi, and a Side-View
N° XII. But before their taking this Form,
he perceived them fometimes in another
Shape, different from the firft defcribed, and
fuch as is fhewn Nquot; x; which, he fays, was
the Figure they appeared in when they
were weary with catching their Prey, or lay
in wait for it.

Noneof them lived more than three Days:
and 'tis remarkable, that notwithftanding
frefh Water was given them two or three
Times a Day, yet in a few Hours it would
flink to a Degree fcarce conceivable, and
that too, at feveral Yards Diftance, tho' in
proportion to the Water all the included In-
feds were not more than as i to 1,150,000.

muft the Effluvia from the Bodies of thefe
little Animals be, that can fo foon and fo
ftrongly infedt fuch Quantities of Water and
Air! This perhaps makes it neceffary for
them to live in a rapid Stream, left they
fliould be poifoned with their own Perfpi-
ration,

The largeft of them exceeds not tV of
an Inch in Length and tV of an Inch in Dia-
meter : they feemed rather foft and flefhy
than cruftaceous, and their Colour was a Kind
of ycllowi£h grey.

At the Beginning of February 1748-9,
I received from the famecuriousPerfon
two Pieces of the .Twigs of an Afti Tree,
(juft cut when they were fent) of about half
an Inch in Diameter. Each of thefe had one
of its Sides covered thickly from End to End
with Numbers of little Spots, not larger than
very fmall Pins Heads, and rather long than
round. Their Colour was fomewhat diffe-
rentfromthe Bark on which they were placed,
and an attentive Eye could perceive they
rofe a little about it. On crufhing them, a
Liquor red as Blood iifued out and each
Spot, when examined by the Microfcope, was
found to be of a filky Subftance, adhering
clofely to the Bark, and ferving as a Coverincr
or Neft to 30 or 40 Ova, which on remov-
ing this Covering with the Point of a Lan-
cet prefented themfelves to Viewi much re-
B h 2nbsp;fembling

372 InfeBs-^n the Bar^ of the Ajh.
fembling the Aurelice of Ants in Shape, but
a thoufand Times more minute, and of a
beautiful fcarlet Colour.

This Difcovery excited a ftrong Defire of
learning what Kind of Animalcules thefe lit-
tle Ova would produce.; but thofe in my Pof-
feftion never came to any thing, being, I fup-
pofe, deprived of a due Degree of Moifture
by the drying of the Twigs. My Friend's
Diligence ho.wever fupplied this Defefl • for
fticking a Bougb covered with them into the
Ground, in his Garden, in a warm Corner
where the Sun could ftiine freely upon it,
prodigious Swarms were hatched of beauti-
ful little Infeds of a fine Scarlet Colour,
whofe Figure is given N° xiii. O.—Their
Back is fomething like that of the Wood-hufe
or Sow-, and in other Refpeds they difl^er
not greatly from that Anin^al in Form : but
are armed with a large ftrong Pair of For-
ceps, which the Wood-loufe has not.

'Tis a pleafing Entertainment to fee them
•creep out of their filken Cafes or Coverings,
at an Opening in the Cafes at one End,
left there probably for that Purpofe by the
Parent Inlecf, when ftie wove this Integu-
ment over her little Brood to preferve them
from Injury; in like Manner as many Sort»
of Caterpillars leave Openings, or a much
loofer Spinning at one End of their Pods,
through which after their Change they may-
be able to come forth. See Nquot; xiii.

And it is worth remarking, that every fmgle
ïnfedt, befides being inclofed in this Covering
of Si]k, which is common to 30 or 40 of
them, has a pure white tranfpai-ent Cafe or
Shell, which being left by the Infedt nearly
refembies the Shape of an Hen's Egg -, and if
they are not difturbed at the Time of hatch-
ing, moft of their Egg-ftiells will be found
empty under the common Coverture. And by
attending to them a little, one ftiall fee, at the
fame Time, feveral of thefe Infects-hatched,
fome juft breaking out of their Shells, and
others creeping about with their Shells hang-
ing to their Tails, as at Nquot; xiii.

My Friend's Account fays, that the largeft
of thefe Animalcules meafured little more
than the 114th Part of an Inch in Length,
and the 200th Part of an Inch in Breadth;
and confequently the Number of them re-
quired to cover a fuperficial Square Inch
would be fomething more than 22800

His Method of finding their Magnitude
was as follows.—In order (fays he) to be
certain of the magnifying Power of the Glafs
I made ufe of, (which was the third Magni-
fier) I divided a Line, drawn exactly an Inch
in Length on a Slip of round Glafs, into 20
equal Parts. Then placing this Slip of Glafs
under the Microfcope, I threw the magni-
fied Image of one of thefe 20th Parts upon

a Scale of. Inches feen by the naked Eye, ac-
cording to Dr. Hooke's Method*) and found
it coincide exaâly with 4 Inches : and confe-
quently that the Glafs magnified 80 Times.

Then taking my divided Inch from under
the Magnifier, in order to make ufe of it in
the fame Manner as I before had done of
the Scale of Inches, I caft the magnified
Image of one of thefe Animalcules on my
Scale of Twentieths of an Inch feen only by
the naked Eye, and found its Length to
cover 14 and . its Breadth 8 of thofe 20th
Parts . of an Inch,—But the Meafures of
44ths and ^-„ths being only the apparent
Dimenfions, they muft be divided by 80,
the magnifying Power of the Glafs, to give
the real Size of the Animalcule, which will
then be found to be t-s'w in Lçngth, and
j^Win Breadth: which Fraétions reduced to
their fmalleft Denominators will be
(nearly -ri th) and : or taken decimally,
^rAJA-oth, and rA-o-th Parts of an Inch.

H E Animal fliewn atN' xiv. Plate
^ XIV. was found, with feveral others
of the fame Kind, fticking to a large Carp,

juft taken out of the Canal in St. James's
Park, It was about one Tenth of an Inch
long, and nearly as much in Breadth at the
broadeft Place. Its Back was covered with
a Shell, (or rather pliable Scale) of the Fi-
gure reprefented in the Drawing : this Shell
was fo extremely tranfparent, that the finny
Legs, of which it has four Pair, befides two
ftiorter Claws, might be feen almoft as
clearly through it as if they had no Covering;
and on each Side the Body of the Animal,
at equal Diftances therefrom, were many cu-
rious and beautiful Ramifications, fomewhat
opake, extending a confiderable Length, and
feeming either to be Blood-Vefifels, or muf-
cular Procefi'es connedting the Body with the
Shell.

The Tail vi^as a Kind of fcaly double Fin,
not unlike thofe at the Extremity of a Lob-
fter's Tail, but exceedingly tranfparent, and
each Half or Fin was marked with one fingle
black Spot, as in the Plate.

The Eyes (which for the Sake of fhewing
them to more Advantage are greatly magni-
fied at fig. K. I. I.) were very fingular in
their Strudlure, being neither fmooth fingle
Balls, like thofe of moft Quadrupeds, Birds
and Fifties; nor pearled Balls like the Eyes
of many Infeds ; but in this Animal each
Eye was compofed of a globular Body, almoft
incircled round with fmaller Globules, as the
Drawing reprefents.

Between the Eyes appeared two Pair of
fhort ftrong Spines, one Pair whereof point-
ed forwards and the other backwards: I
know not whether thefe ferved as Feelers,
or were Weapons of Defence or Offence.
At a little Diftance below the Eyes were
placed two large cylindrical or rather fome-
what conic Suckers, compofed of feveral
Annulu feemingly like thofe that form the
Windpipe in Birds and Bcafts. The Animal,
by Means of thefe, adheres and fixes itfelf fo
ftrongly to the Fifh it preys upon, that all
the Motions and Efforts it can ufe are in-
fufficient to fliake off the little Tormenter,
who is continually feeding on and making it
uneafy. See the Suckers fig. K. 2, 2. Juft
below them at 3, and above the grand in-
teftinal Dufl, lay the Heart,compofed of two
Lobes, which might be ieen to contract and
dilate alternately, as the Hearts of many
other minute aquatic Infedts do.

One of the fliort Fore-claws, which is co-
vered with a ftrong Shell, and armed with
three Hooks at its largeft Joint, is fliewn

This little Creature makes a very pretty
Appearance in the Water, where it is con-
tinually playing up and down, with a Kind
of hovering Motion, like that of the May-
ply in the Air. Sometimes it leaves the
Fifh to divert itfelf for a while in fuch
Manner, and then fettles on it and fixes itfelf

again. The internal Motions of the Bowels,
are prefented fo finely to Obfervation,
by the uncommon Tranfparency of its Shell
and Skin, that it is a moft agreeable Objedl
for the Microfcope; and the Carp is often
peftered with fuch Numbers of them, that
they are not very difficult to procure. They
may be kept a long while with the Carp in
Water, but unlefs the Fifh be with them
they die in a Day or two.

The natural Size of this Infedt, at its full
Growth, is fomething lefs than one of its
Eyes appears in the magnified fg. K.

N^UMB. xv. is the Pidlure of the little
Vermin that infefts the Banfickle or
Prickleback ; whereto it adheres fo firmly
that it is hardly poffible for the Fifti to get
rid of it, unleis it pleafes to unfix itfelf. It is
furnifhed with a Pair of fucking Inftruments
like the Carp-loife, has the fame Number of
Legs or Fins, which are continually in Mo-
tion, whether it be fwimming or faftened upon
the Fifh: and in moft other Particulars it fo
nearly refembles the faid Animal, that after
taking Notice of fome Difference in Shape,

SEVERx^L of the Infeds fiiewn N° xvi.
were fent to me ii-omTarmouth, in a Bot-
tle of very clear Water. Some were about a
Sixth Part as big as the Pidure, and others a
great deal lefs, but none of them alive : having
either been fuffccated by corking the Bottle
too clofe, or fhaken to Death in bringing.
They feem to be of the Squilla Kind, tho' a
Species I have never ieen before or iince; but
theNumbers that were fent make me imagine
they are frequent in thofe Parts.

The Back is cruftaceous, and jointed like
a Lobfter's Tail ; having ten Articulations,
which divide it into eleven Parts, the mid-
dlemoft of which are wideH: ; for they lelfen
from thence to the joining on of the Head
one Way, and grow tapering the other Way
to the Extremity of the Tail, which ends
almoft in a Point, with a Sort of a Horn on
each Side, that extends beyond the Tail. The
Scales of the Back reach down the Sides, and
meet the upper Part of the Belly, beyond
which they ftretch out and overhang a
little. The Belly is fofter than the Back,
10nbsp;and

and from its anterior Part proceed fix Legs,
on each Side three, jointed in an odd Man-
ner, and feemingly but aukward for walking
with. But the moft extraordinary Part- of
this Animal is the Head: a Draught whereof,
magnified a great deal more, is given^. S.—
This Head is arm.ed with a Pair of very ftiarp
hooked Forceps ; between which it is leng-
thened out into a Sort of Probofcis, whofe
Shape refehibles a Duck's Bill, and under
that the Forceps can occafionally be brought
together, or even crofs each other, in order
to fecure its Prey. However, this Probofcis
did not divide nor open like a Bill or Mouth,
neither could I difcover that it had any Per-
foration : which makes it probable, that the
Creature fucks in its Nouriftiment intirely
through the arched Limbs of the Forceps,
in the fame Manner as the Squilla defcribed
fage'^^'i. And indeed our prefent Subjedt dif-
fers little from that voracious Squilla (which
I take it to be another Species of) except
in having a Probofcis; whereas in that the
Forepart of the Head between the Forceps
is remarkably fliort and flat

The Figures M'and N, in this fame Plate,
are two Views of an Animalcule, many of
which were difcovered in Water that had
been kept in a Glais Jar for fome Months.—

* Suppofing the Probofcis away, the Drawing Nquot; xvi.
^vill give a pretty good Idea of the Sjuiila page 358.

It is {hewn at M in the Pofture of fwimming,
at which Time it moves pretty fwiftly with
its flat Head foremoft : its Tail appears di-
vided, and on each Side it extends a fpread-
ing Fin. At N it is fhewn in Profile, and
with its Fins drawn in, as ufually is the Cafe
when it appears at reft.

'Tis about the Size of the largeft xAnimal-
cules found in the Infufions of Hay in Water.

Many of the Drawings in Flate XV.
together with the Defcriptions of
them, were lent me by a Gentleman, whole
true Judgment in the Ufe of the Micro-
fcope, and the Accuracy of whofe Pencil in
delineating therefrom, i have been long ac-
quainted with : and whofe Name, had i
Leave to mention it, would do great Honour
to this Work, as his Friendfhip does to the
Author of it. As it is therefore neceffary
to give his Defcription of thefe curious Sub-rr
jefts in his own Words, i hope it may be
excufable to publifh the whole Letter where-
in they are inferted, though written with the
kind Partiality of a Friend.

I Am glad you are determined to publifh
your Microfcopical Obfervations. There
are few who have been able, like you, to
gain Accefs to the Sacrarium in quo reduBa
et claufa funt arcana Nature fewer ftill
who have Capacity to fmooth the Path for
others, and render the Examination of Na-
ture by the Microfcope eafy, ftiort and plea-
fant: This you have done, and thereby have
acquired a Title to the Obfervations which
by your Book others have been enabled to
make. What I fend you are therefore of
Right your own. They have fuffered indeed
by not being under your Eye j their Defedts
are mine what Worth they may have mufl
be afcribed to the Aftiftance of your printed
Diredions for the Ufe of the Microfcope.

You defire to add to your proper Ob-
fervations, fuch as have been occafionaily
made by your Friends: and as I am fo happy
as to be one of that Number, I fhall here
communicate what has occurred to me ; per-
haps of very little Confequence, but as rerum
Natura facra fua mn fimiil tradit, nec omni-
bus ilia patent, the following Obfervations
may have the Recommendation of Novelty
in fome Degree : and thofe that are not in-
tirely new I fend to you, becaufe they tend
to corred the imperfed or incotnpleat Ob-
fervations already publifhed.

The Drawings I made myfelf, when the
Ohjefts were under Examination, with Mr.
Cuff's Microfcopes, and as exadlly as I could:
and his Glalfes are fo excellent, that if there
fhould be found any Defedts in the Figures,
they muft be attributed to my Inaccuracy
and Difufe of Drawing. However, fuch as
they are, they are at your Service.

If thefe Things fhall appear infignificant,
yet as in complying with your Defire to have
them, they aftbrd me an Opportunity of
fliewing my Regard and Friendlhip for you,
they are grateful and valuable to me.

I lhall firft give you an Account of what
I have met with in refpedt to Water-In-
fedts, which have, formerly, in many Inftan-
ces, been thought imperfedt in their Pro-
dudtion, from the Imbecility of the Element
to which their Creation was attributed: for
aquatic Infedts may certainly be compre-
hended under Animalia aquatica, which Se-
neca calls, tarda et informia, ut in aere caco
finguique concepto. But Attention to the
Works of God makes manifeft, that the
Heavens do not only declare his Glory;—
Jupiter eji quodciinque vides. And indeed
whoever fearches the Waters will not find
his Curiofity difappointed; there he will fee
the Works of God difplayed to thofe who
delight in them ; and perhaps with greater
Variety and more Profufion than any other
Element.

Fig. I. Plate XV. is an aquatic Infeft of
which we have two Drawings and Accounts,
both very fhort ; one in the Phil. Tranf. 288,
the other in the Letters of Mr. Leeuwenhoek,
Epiji. 121 : and as this Infect has no Name,
I will venture to call it the Pediculus aquati-
cus ; for the Infed to v/hich Goedart gives
that Name, is now allowed to be the Pulex
arborefcens, or arbor eus of Swammerdam. This
Infed is a common one, and of the crufta-
ceous Kind, but being pretty tranfparent it
is a beautiful Objedt in the Microfcope.
When it is fwimming it appears as Jig. i. It
has five Pair of Legs ; the firfl Pair on the
Side of the Head are the longefl it has the
four other Pair are fliort and upon its Belly :
the firft and fécond Pair are only vifible as it
fwims. The Back is guarded with large
Scales which proceed all the Way to the Tail,
but from the eighth Scale they are frequently
covered fo thick with Hair, that only the
Joints or Divifions are difcernable j but in
other Poflures, as in Nquot; 3, the Scales are
vifible all the Way to the Tail. —The
Tail is divided into two, with Hairs iffuing
from the Extremities of each Divifion, which
in fwimming are kept extended as in^.
1. The , Colour of this Infed is a pale
brown.

Fig. 4. fliews the Infed upon its Back,
when all the Legs were vifible; only the

three lovveftPair were laid back upon its Bo-
dy, and kept in a conftant Motion among the
Hairs which cover its Belly, as if bruftiing
itfelf. Nearer the Tail appear two Bags or
Paps, hanging down, with a round Part at the
Extremities, fet with a few Hairs. I at firft
imagined thefe were the Receptacles of its
Spawn, but have fince found the Spawn pla-
ced much lower under the Tail: fo that if
this be the Place of the Spawn in the parti-
cular Infed: thefe Drawings were taken from,
there may be different Species of thefe Infeds.

Fig. 3. is the fame Infed reclined on
one Side, when the Scales are moft confpicu-
ous as they unite; eight of its ten Legs are
vifible, and only one of the Paps appears
hanging down-

It is faid in the TranfaSiions that this In-
fed is monoculous 1 and indeed it is not eafy
to difcover its Eyes they are placed in the
Middle of the Head between the firft Pair of
Arms, and appear as in jig. 2. But it has
two Eyes joined at the Bottom, both coni-
cal, and apparently feparated towards the
Vertices as at jig. X. which fhews thefe Eyes
greatly magnified. When the Head of the
Infed is bent down, they may eafily be mif-
taken for one Eye, as is evident from their
Appearance in jig. 3.

Mr. Lecuwenhoek'amp; Painter has given us a
very bad Figure of this Infed j his Account

Mentions the Manner of its carrying the
Spawn. In fig, 2. towards the Tail, the
Spawn Bags (at leaft what I believed fuch)
were more extended than in any of the
other Figurfes, but no Spawn was difcovered
in them ^ and fince thefe Drawings I have
examined more of the Pedkuli aquatki, and
find the Spawn fixed to the Tail much lower
than thofe Bags, and adhering to the Tail by
two fine Ligaments, which are eafily broke
by the Infeft's ftirring itfelf in the Water ;
and fometimes all the Spawn comes away
fticking together, but oftener feparated and
difperfed among the Water. But though I
have kept the Spawn fome Time, I never
could find the young Infedls in thé Water,
which Leeuwenhoek fpeaks of; but perhaps
I have not had mine when the Spawn was
come to an equal State of Matriuty. I have
fent you this Account, becaufe the former
Figures of this Infedf have been'extremely
imperfeót in all Refpefts, except the Spawn,
which in Mr. Leeuwenhoek'^ Drawing is ex-
adl enough *, and alfo as I found the Opinion
received that this Infedl varied from all others
in being monoculous.

Exom finding this little Creature very frequently with
its two Bags of Spawn adhering to its Tail, (as may be feen
Plate IX.II. of the Microfcope made eafy, in the Drawing
there, taken from Mr. Leeuiuenhosk,) I have been accuftomed
to call it the Bag-Animal,

The two Figures 5 and 6 are I heller®
only different Appearances of the fame In-
fed, altho' there is fome Variation in the
Make of the Shells, but in all other Refpeds
they agree. I at firft took this Infed for
the Fulex arborefcens, and certainly it may be
clafied with it: but comparing it with Swam-
merdam^ Figure, it by no Means agrees
therewith, nor with that which you ftiewed
me*; for in this there are four Brachia
ramofa, in the other only two; thefe here
are lower, and proceed from the Infed un-
der the Shell, the others are on each Side
the Head and from the Shell. This Infed
has two Antenna, and that has none, but a
Bill like a Bird's.—I have drawn thefe as
they appeared fwimming with their Backs to
the Eye, where the joining of the Shells is
vifible, which feemed ridged or marked with
black Streaks as in the Figures i the Colour
was a deep brown.

In fonie Pond Water, with the Lens pa^
lujlris I found the InfeSs of which I fenfi
you the Dra'wings,fg' 7- and 8. The firft
of thefe, fig. 7. was contained in four very
thin tranfparent Shells, The two upper
Shells united on the Back, and declined down
the Sides till they met with two under Shells,
making at the joining of the Sides acute

Afiglesgt; and at their joining on the Back
and Belly obtufe Angles; but the upper
Shells projedted beyond the lower, which
appeared beyond the upper towards the Tail,
and probably by this Means thefe upper Shells
ferved the Infedt inftead of Fins, and to keep
it up in the Water. All the Shells were
elliptical.

The Figure reprefents the Infect fwim-
ming, when the Head appeared beyond the
Shells without any Antennae or Feelers : the
Tail was divided and extended : the Body
was very apparent, and that Part which is
on the Back in the Middle was in a con-
ftant Motion, alternately contra6ting and di-
lating. From eaeh Side below this Part there
appeared a Ligament, terminating at the
Circumference of the upper Shells, and may
perhaps ferve to keep the Shells fteady, or
to move them, if they be nooveable, which
I could not difcover, for the Motion of the
Infedt is very equable and fmooth.

Fig. 8. is an Infedt which I am apt to be-
lieve is the fame as fig. 5. in another Polture,
as it ftands feeding in the Water : Tor it a-
grees in Colour and in the Shell exadtly : the
Antennas and Arms have as near a Refem-
blance as can be expedted in fuch differing
Pofitions. It has indeed two Legs behind,
wherewith it fixes itie;f to the Glafs, which
do not appear in the other; but if they are
«nly to fix itfelf, they may be covered-under

the Shell when fwimming: however thefquot;^
is fome Difference in the Appearances. This
Infed fwims well and nimbly, and by a ra-
pid Motion of its Arms makes a ftrong Cur-'
rent to bring it Food: (which Manner of
feeding by a Current or an Eddy is common
to many other Water Animals:) indeed, the
Swiftnefs with which it moves not only
the two Arms that are extended to draW
Things to it, but alfo thofe thatare bent back,
to drive along each Side what is not fit for
its Food, and the Way they co-operate all
together to make a ftrong Stream, is incon-
ceivably curious, as v/ell as its Conftancy
and unwearied Application. When it is difgt;
turbed it draws itfelf intireiy into the Shell,
and then appears not unlike a fmall Frefh
Water Mufcle.

The Infed 9. is very uncommon : I
never met with any more of the Kind, nor
with any Account of it. At firft, when I
found it among fome Water in a Leaden
Ciftern ftocked with the Nymphce Vermiculi
of the Gnat, I fancied it might be the Ver-
miculus of that Infed j efpecially as the Head
was not very unlike it, and it had pulmona-
ry Tubes towards the Tail, as the Nympha
Vermiculus has one. But as it never chang-
ed its State during three Weeks that I kept
it alive, though the Gnats changed much
fooner, and it has many different Parts from

^ The natural Length of this Infed was
■roth of an Inch, and its Breadth at the
Shoulders or broadeft Part of an Inch,
according to the moft exad Dimenfions I
was able to take. Its Colour was a pale Red
or Pink, which appeared deeper at the join-
ing of the Rings, but tranfparent. The Head
Was covered with a Shell, of a light Brown,
With two fmall Eyes fet round with Hair, as
was alfo the Mouth, or at leaft that Forepart
of the Head on each Side of which it had
the Antennœ bending inwards ; but without
Hair or any Joints between the Shell of the
Head and the firft Ring of the Body ; the
Neck Part which appeared being a Continu-
ation from the Head. Its Body confifted of
eleven Rings, tapering fomething all the
Way to the Tail, but the two firft and three
laft Rings not fo wide as thofe in the Mid-
dle. Under the firft and fécond Ring it had
two Legs, (of which one only could be re»,
prefented in the Figure) and their Extremi-
ties were fet round with Hairs : between the
tenth and eleventh Ring two fmall Tubes
arofe, making an obtufe Angle with the
Forepart of the Infe6t's Body, but an acute
Angle with each other : the Ends of thefe
Tubes were fet round with Hairs and feemed
to be open : I take thefe to be pulmonary :
pot that the Infed always kept thejn upon

the Surface of the Water, though it oftert
brought itfelf up till they were there, but
becaufe in other InfeCls fuch like Inftru-
inents of breathing have been obferved.

From the eleventh Ring the Tail begins ;
which is reprefented as it appears when the
Infeét ufes it for fwimming, and the Whole
of it is moft vifible. It does not however
keep it in this Pofture when fwimming, but
alternately extends it on eaph Side and brings
it together again as Men do their Arms in
fwimming. The Ends of each Branch of
the Tail are fet round with Hairs, and there
feems to be a Joint in each ; but the Draw-
ing will give you a better Idea of it than any
Words. — I mufl not however omît faying
fomething of its Inteftines. On each Side
there is a fmall Veffel running from the Head.
to the Tail, in which a conftant Circulation
of a pellucid Fluid was difcernable : from
the fécond Ring to the fourth a dark-colour-
ed Veffel appeared, with the End next the
Head feemingly open, or if covered, it was
with a light-coloured circular Tegument.
This Veffel terminated in a fine Canal that
feemed to enter another Bag of a clear white
Colour, at whofe End was a Gut or Canal
that went quite down to the Tail. This Bag
or V effel I conjedured might be its Stomach.
Above this Gut, and at the feventh Ring, be-
gan another Veffel or Ligament, I can't tell
which ; reaching (after crofting itfelf twice)

to half the tenth Ring, and there ending
abruptly, without communicating with any
other Part j fo that unlefs it be an Inftru-
ment for contrading the Body of the Infed
in walking along the Bottom of the Veflel
it is in, it feems only a Proviiion for fome
other State it is to affume.—1 forgot to ob-
ferve, that when the Infed fwims it ufes al-
fo its Fore-legs, bringing them up clofe un-
der its Head, and moving them back clofe
under its Belly.

If I could have found any more of this
Kind, fo as to have ventured killing it, by
viewing it in the Solar Microfcope I might
have given you a fuller Account of it, efpe-
cially of the Inteftines : but as I was curious
to difcover what Changes it might undergo,
I was very tender of it; however I was dif-
appointed, for it died after I had kept it
three Weeks from the 5th of September, and
in a Week after it was gone to Pieces, fo
that I could not bring it to Town toftiew it
you as I intended.

Fig. 10. the only one of its Kind I have
ever feen, is an Infed called hy Monfieur de
'Reaumur le Vers a queue de Rat, the Wortn
/with a Rat's Tail, of which he has given an
accurate Account, Mem. ii. Vol. of his ex-
cellent Memoirs. It is it feems the Vermi-
cules of a Fly with two Wjngs ; and if J

• lit changes to a Sort of Gad-Fly or Breeze, about the Siz«
Snd Colour of the common Bee, having only two Wjngs : th?
Tail fart broad and flat, and without any Sting.

had had his Book when this Infed was
found, Ifhould have made freer with it than
I did, and not have preferved it to obferve
its Change'of State. The Drawing of it I
fend you, and for an Account of it refer you
to Morfieur de Reaumur.

This Infed was found in a Ciflern of Rain-
Water in Auguß. The Length of its Body
was 4 of an Inch, but its Tail was four Times
the Length of the Body, though not extended
near fo far as it was capable of being. Above
Half of the Tail was covered with a fine
Down,, in fmall circular Divifions, as the
whole Body was: this Down or foft Sub-
ftance is of a fine reticular Make, and at the
Head there appeared two Antennae within
the outward Coat, which the Infed by Means
of thefe Antennae fpread out or dilated at
Pleafure : fo that the downy Covering feem-
ed not fo properly Part of the Infed as to
contain the Infed. There were Fibres vi-
fibly crofling upon the Back, and running
down to the Tail : And near the Tail, be^^
ttveen thefe, a VeflVl of a black Colour ap-
peäred, growing gradually lefs to theExtre-
quot;fhity. The Colour of the Infed was a pale
Affi, th0 Tail and Antenna black, the Extre-
mity of the Tail fet with Hair.

I take th'S Infed to be the fame with the
Rat-tail'd Inf.d of Monfieur de Reaumur, but
by the Figure you will fee it does not in all
l^efpdes agree with what he has defcribed:

perhaps the Flies of which thefe are the
Worms, or the Nymphas, may vary in Eng-»
land from thofe in France, where certainly
they are more common than here. The
principal Difference is in the Legs, of which
this had only fix Pair, his feven : the Ends
of them v/ere fet round with Hairs, and juft
under the Tail was a fingular Fin, double,
joined at the lowed Part in an acute Angle,
and from thence growing fmaller 'till it came
to the Body. By Means of this Fin, as a
Rudder, it fi:eered itfelf in the Water, on the
Surface of which it kept the Extremity of
its Tail : and when Water was added, it
lengthened its Tail as much as it could : and
if that did not reach the Surface, it raifed
itfelf higher, exadtly as Monfieur de Reaumur
obferves, and about the fame Length, (near
iive Inches,) before the Infe£l was obliged
to leave the Bottom of the Glafs.

I Ihall now defcribe an Infed not found
in Water, and very common in Time of
Harveft, but of which I have never feen any
Drawing or Account. It is called the Har-
vefi Bug : is of a bright red Colour : fo very
fmall as to be imperceptible to the naked
Eye, and on the Point of a fine Needle re-
fembies a Drop of Blood. A Drawing taken
from the Infed preferved in a Slider, and
, greatly magnified, is given fig. 11.
■ I had often heard of thefe Infeds, but did
not give intire Credit to what I heard,'till a

Lady taking this out of her Neck convinced
me of their Exiftence and Tafte, They arc
extremely trouhlefome to thofe that walk in
the Fields in Time of Harveft, efpecially to
the Ladies, for they know what Skins are
fineft and eafieft to pierce. They have at the
Head a Probofcis near of their own Length •
by which they firft make Way through the
Skin, and then bury themfelves under it,
(leaving no Mark but a fmall red Spot) and
by their fucking the Blood create a violent
^chmg ; a good Remedy for which is a little
Hungary Water ; though perhaps Spirit of
Wine with Camphire might be more de-
ftrudive to thefe little troublefome Attend-
ants of Summer Walks. They are I believe
frequently carried in the Winds at their Sea-
fon, for I have fince known them attack
Ladies in a Garden, which was defended
from a Corn Field by a Wall, too high fop
thefe Infedrs to get over any other Way.

They have three Legs on each Side, with
four Joints fet with Hair, as the Body is all
round. The firft Pair of Legs arife from the
Back, juft below the Eyes : the other two
Pair from the Belly : it has alfo two fliort
AntenncE, one from each Side of the Head,
which appears with a Divifion in the Mid-
dle. I have fometimes fufpedted this little
Creature might be a young Sheep-Tick,
irom Its Figure and Way of burying itfelf :
but then it fliould be found rather where

Sheep feed than in Fields of Corn, growing,
and before Sheep are fuffered to come into
thofe Fields : and it is never got as I have
heard in Grafs Fields, unlefs bordering upon
Corn ; but amongft Wheat it never fails. If
^ny one has a Mind to make Trial upon this
Infed, how it comes to be amongft Corn
.only, and yet lives by fucking of Blood, he
may eafily find Abundance of them: for
though they prefer the Ladies, yet they are
fo voracious, that they will certainly lay hold
of any Man's Legs that comes in their Way.

I intended to have fent you an Account
and the Figure of the young Plant found in
the Kidney Bean, but as that has been already
accurately obferved by Dr. Grew in Ana-
tomy of Plants, I need not trouble you with
it: I'ftiall therefore only take Notice of the
Seeds of two other Plants which have not
hitherto been obferved, as far as I know. _

In the Seed of the Lime Tree, which
arifes from a Stalk in the Middle of the Leaf,
(as reprefented N° l.fig. i.) there is a young
Plant to be found, when the Seed is ripe, to-
wards the Beginning of October.

The Seed of the Lime Tree is covered
with a rough Skin, within which there is a
Shell, but not hard ; if this Shell be carefully
opened there will appear a thin white Juice,
inclofing fix Pods or Bags, all tied together,
and adhering to that h nd of the Seed which
iS joined to the Stalk, with very fine Fibres
^ ■■nbsp;running

39^ Seed of the Lime Tree.
running up the Infide of the Shell, and ap^'
pearing zsfig. z. Thefe Pods when taken,
out of the Shell appear as fg. 3.

As the Seed advances in Maturity this
white Juice grows harder,'till it is quite ripe,
and fome one of thefe Pods has robbed the
reft of Nouriftiment, by taking place within
tlie Kernel, where it expands and excludes
the reft, which will now be found flicking
to the outward Cover of the Kernel dried to a
brown Colour, with their Fibres embracing
the Kernel, ferving only as Cords to keep the
Nouriftiment of their more fortunate Brother
together, and appearing as fg. 5. So that if
we follow the Opinion of Swammerdam, and
Fo/taire in his Metaphyfics of Sir Ifaac New-
ton, page 54 of the Englifti Tranftation, that
we fee in Things a Difenvellopement only, here
the Author of Nature has provided in one
Seed fix Vermiculi, one of which alone-is to
become a Nympha Plant: for I never met
with any Seed which contained more than
one young Plant, in that State, which under
Voltaire^ Authority, I may venture to call
the Nympha State.

When the Seed is come to a fufficient
Confiftence, and ready to drop from the Tree,
if it be opened it will appear as fg. 4 : the
Infide filled with a white ftiining Subftance
incloflng a deep green Plant like a Flower,
which arifes by a fmall Fibre from that Part
pf the Seed to which the Stalls adhered, and

perpendicular to it. The Plant when taken
out, and viewed in the Microfcope, appears
as at fg. 6. All the Fibres of the Leaves are
difcernable, altho' the Leaves are themfelves
thicker in proportion than thofe of the Tree,
and feemingly turgid with Juice. Thefe
Leaves are double, and fo tender and foft
that I could only with the fineft Needle fe-
:)arate them a little towards the Top, as I
lave endeavoured to reprefent in the Draw-
ing. ^

N° IL is the Seed of Afparagus.— 'Pig. 1,
is the red Berry as it grows from the Stalk,
which contains, in a foft watery Pulp, fix
black fliining Seeds, formed as I have tried
to reprefent at fig. 2. Their Appearance,
whichever Way you view them, reprefents
that Shape which Bellini calls Pelecoides.
Each of thefe Seeds contains a hard white
fliining Subftance with bright fmall Specks
all over it; and, lying horizontally, a fmall
Plant, white indeed, but with a yellow Caft,
plainly different from the Parenchyma in
which it is fituated. This Plant examined
in the Microfcope appears ^^ fig. 4. with
bright Spots like Papillae all over it, and the
bending Leaf at the Top tending to a faint
green. When the Plant is taken out the
Section of the Seed appears as^. 3. in which
the Bed of the young Plant runs quite
through the Parenchyma, from one Side of
the Covering or outward black Film to the
other.

Altho' I fhall endeavour to follow the
learned Mr. Hookes Advice to thofe who
fhould Gorrefpond with the Royal Society *
to fend the Kernel of Fad flript from the
quot; Shell of Impertinencies,quot; yet you will
give me leave to obferve two Singularities in
this young Plant of the Afparagus. Firjl^
tliat its Pofition in the Seed is very different
from mofl others: this lies horizontally, and
not perpendicular to the Jundure of the
Stalk, as others generally do; and indeed
though I have feen many Seedling or Nym-
pha Plants, I never rnet with one pofited as
the Afparagus is. Secondly, it has no Fibres
or Ligaments communicating with the Seed
in which it is inclofed, but lies in it as a Ni-
dus, adhering only by filling the hollow Bed
cxadly.

I have now given you an Account, and
I fear a tedious one, of fome Things unob-
served before, I believe, which have occurred
to me: from your Friendfliip I am perfuad-
ed I need make no Excufe for it; if I was
to make one, Pliny the elder (et ille etiam
Caufas aBitavitJ tell you my Sentiments
as well as his own, inter crimi'nu ingrati ani-
mi et hoc duco, Naturatn ignorare.

IN my former Treatlfe on the Microfcope,
I took Notice of the JJnning Light fre-
quently found on the Shells of Oyfters, as
being produced by three Sorts of Animal-
cules, which are there defcribed, according
to the Account given of them by Monfieur
Auxaut I had then no Opportunity of
adding any Figure to that Account: but hav-
ing not long ago been favoured (by a Friend
whom I can depend on) with the Defcrip-
tion and Drawing of one Sort of Animal-
cule, which he had obferved to occalion fuel*
Light, I fhall infert it here.

Having (he fays) been fometimes fur-
prifed at the Sparks of Light to be feen oa
the Shells of Oyfters, on removing them, or
llriking on them, when newly taken from
the Sea; he beftowed fome Pains to find
out the Caufe; and after many Examina-
tions became perfectly convinced, that thefe
Ihining Sparks are lucid Emanations from
a minute Infed, differing in its general Form-
but little from the common Scolopendra.
This Infeft he carefully made a Drawing of
from the Microfcope, an exad Copy of

which is given at Letter A.——Its Lengtli
was about the -^th audits Breadth rather more
than the locth Part of an Inch.

The- Body conMs of twenty-eight Joints
or Divifions, exclufive of the Head and Tail
Parts: each of thefe Divifions has a Pair of
Feet belonging to it, (viz. one on each Side)
making the whole Number of its Feet 56,
or twenty-eight Pair : they are all fliort and
befet with Hairs.

The Tail Part is larger than any of thé
other Divifions, and has three pretty long
Spines or Briftles proceedingtherefrom. The
Head is remarkable, on Account of its being
armed with a Pair of Forceps uncom.monly
long and large in proportion to the other
Parts : beginning much farther backwards
than is ufual in other Animals, and reach-
ing beyond the anterior Part of the Head, in
a Manner very convenient for feizing its
Prey and carrying to the Mouth any thing
it takes hold of. It is furniftied with a Pair
of Horns, and has befides at the Snout two
fhort Antennas or Feelers.

This httle Infeft can emit or conceal its
Light: and fometimes its Luftre is fo bright
as to be difcoverable even in open Day-light,
efpecially on being touched or difturbed

Its Light is blueiih like that of the Glow-
worm, or a Spark of burning Brimflone.—-
My Friend obferves, that our fmall Land
Scolopendra has likewife the Property of ihin-
ing in the Dark, which indeed has been
taken notice of long ago *.

fays, that opening Oyfters he found this Animal between two
Shells which ftuck together. It was alive, but faint. Perceiv-
ing it emitted Light in the Shade, he carried it to a dark
Place, where by irritating it on the Back with a Pin it Ihone
pretty ftrongly more than once. The Light appeared on its
Back towards the Tail, chiefly in two Spots; but, when more
violently irritated, it was fometimes feen darting along the
Back ; and, particularly once, it was illuminated in StreaKs up
to its very Head. The Infeft growing more languid, he put it
between the Shells where it was found, in fome Water wherein
Salt was dilfolved, hoping it might revive; but in an Hour
it was quite dead.—'Tis about | of an Inch long, and i of an
■ Inch in Breadth j in Figure flat, with many Fins along its
Sides from End to End.

* Mouffet writes, that his Friend Mr, Brewer found twicc
by Night in the Summer Seafon, amongft Heath and Mofs,
the Jhining Scolopendra, lucid and fiery ; its whole Body
emitted Light, but fomewhat fainter than the Glow-worm.
Mr.nbsp;farther fays,—quot; Happening to come home one

Night in a Sweat, and in the Dark wiping my Head with a
Linen Handkerchief, the whole Handkerchief appeared to
me fliining, and as it were on Fire ; and whilft I viewed this
feeming Miracle with Surprize, the Light was all collefted
in one Spot: whereupon folding the Handkerchief together,
I called for a Candle, and on opening it difcovered one of thefa
Scolopendra, which by being rubbed about my Head, had
fpread over the whole Handkerchief I know not what kind
of flaming Vapour.quot;—He affirms it was like the Scolo~
fendra found in Gardens under Stones and Flower Pots. Vid,
Thealrum Infe£i. Cap. xv. De Cicindela.

I take this to be the Kind of Scolopendra Mr. Willou^hhy de-
fcribes, lying rolled up amongft Earth and Dung : Its Colour
a brown or whitifli yellow, the Head of a pale cheftnut. hav-
ing two Antenns; its Length half an Inch, its Tail forked t
VCL. II.nbsp;D dnbsp;its

It feems not improper to fay fomewliat
in this Place concerning the fhining of Sea
Water; fince, not without the Appearance of
Reafon, it has been fuppofed owing to vaft
Numbers of luminous Infeds, of which pof-
fibly in the Waters there may be various
Kinds as well as upon the Land.

A curious Enquirer into Nature dwell-
ing at Wells, upon the Coaft of Norfolk, af-
firms, from his own Obfervations, that the
Sparkling of Sea Water is occafioned by In-
feds. His Anfwer to a Letter wrote to him
on that Subjed runs thus : quot;In the Glafs of
Sea Water I fend with this are fome of the
Animlacules which caufe the Sparkling
Light in Sea Water 3 they may be feen by
holding the Phial up againft the Light,
refembling very fmall Bladders or Air
Bubbles, and are in all Places of it from
Top to Bottom, but moftly towards the
Top, where they afiquot;emble when the Wa-
ter has ftood ftill fome Time, unlefs they
quot; have been killed by keeping them too
long in the Phial.

Placing one of thefe Animalcules before
** a good Microfcope, an exceeding minute

One Evening after Raiti, fays Mr. Ray, I found a fmall
Scokpendra of this Sort fiiining like a Glow-tsiwrn ; 'twai
covered with a flimy Matter, which being wiped away, it
ceafed not to fliine. Vid. Ray, Hiß. InJeäQrum, page 45.

Worm may Be difcovered, hanging with
its Tail fixed to an opake Spot in a Kind
of Bladder *, which it has certainly a
Power of contradling or difiending, and
thereby of being fufpended at the Surface,
or at any Depth it pleafes in the including
Water.quot;

The above-mentioned Phial of Sea Water
came fafe, and fome of the Animalcules
were difcovered in it, but they did not emit
any Light, as my Friend fays they do upon
the lealt Motion of the Phial when the Wa-
ter is newly taken up. He likewife adds,
that at certain Times, if a Stone be thrown
into the Sea, near the Shore, the Water will
become luminous as far as the Motion reach-
eth : this chiefly happens when the Sea hath
been greatly agitated, or after a Storm.

Jof. Vianelli, M. D. of Chioggia in Italy, in
his Enquiry into the fliining of Sea Water in
the Night Time (which, he fays, is feen
with Wonder in the Lakes of Chioggia, from,
the Beginning of Summer until Autumn, ef-
pecially where Sea, Weeds abound), relates,
that he brought from thence, one Summer's
Night, a large Velfel of this Sea Water,
which being fl:irred about by his Hands in
a dark Clofet, fparkled very much ; but after
it was filtered through a clofe Piece of Li-
nen it afforded no Light at all, notwithfliand-

• A Drawing of this came with the Account, but it was
too late for the Engraver.

ing all the Motion that could be given it,
v^^hilft the Linen appeared covered with
numberlefs lucid Particles, thereby proving
the Light to be fomething diftinft entirely
from the Water.

Then examining fome of the Sea Weeds,
he perceived thirty at leaft of the like fliin-
ing Particles i1pon every little Leaf, and Awak-
ing them over a Sheet of Paper, one of ths
fhining Bodies was thrown upon it, which
being wrapped up in the Paper emitted
Light quite through it. Unfolding the Pa-
per, and viewing this luminous Body atten-
tively, he found it far lefs than a fmall Hair,
extremely delicate and tender, and of a deep
yellow Colour : and by the Help of a Mi-
crofcope he difcovered it to be a living Ani-
malcule, of a curious and fingular Strudlure,
and could not enough admire the Splendour
of its Light. It was fomewhat like a Ca-
terpillar, and confifted of eleven Segments
or Ringlets, along which near the Belly were
a Kind of Fins or Inftruments of its feveral
Motions. From its Head iflued two Horns,
and the Tail appeared twifted.

He obYerves, that thefe glittering Sea Wa-
ter Infefts are entirely luminous, whereas
the Glow-worm emits Light only from a
Part about the Tail; and, moreover, that
when at reft they do not fliine at all, though
they fend forth a prodigious Brightnefs as
foon as their little Bodies become agitated.

Hence he accounts for the Fifhermen's fore-
telHng a Tempeft from an extraordinary-
glittering of the Sea and Lakes : thefe Ani-
malcules, as he fuppofes, being difturbed and
put in Motion at the Approach of fuch a
Change.

Thefe Animalcules are found, he fays, at
the Beginning of Summer, more plentifully
amongft the Weeds than in any other Part
of the Water : but they increafe furprizingly
in a fhort Tim.e, and difperfe themfelves in
the Waters evry where

In Tlate xv. b,c, d, reprefent a very fmall
Infedt found in fome Ditch Water, b and c
fhew it in the Adion of moving from Place
to Place, which is performed by faftening
the Tail-End upon the Plate of Glafs, bend-
ing the Body, extending and directing the
Head downwards, then fixing the Head and
drawing the Tail to it, whereby is made
what may be termed one Step: and by re-
peating thefe Steps its Progreflion was pretty
nimble, and much refembled that of the
Species of Caterpillars called Loopers. Its
Poflure when at reft, after being tired with
Motion, or juft before it began to fet for-
wards, is feen at d.

I could not by the ftrideft Obfervation
difcover any fuitable Apparatus about the

* A large Account of this may be feen tranflated from the
Jialiatti in the Univir/al Magazine, for De;mber, 1753-

Head, or elfe from its Appearance fhould have
judged this little Creature to be a Species of
the Wheel-Animal, which it imitates in other
Refpedls very nearly.

O S T living Creatures are fuppofed
_ to have their Lice, Fleas, or little
'ormentors, of Kinds and Forms peculiar to
themfelves: fuch have been found in great
Numbers on many Sorts of Beafls, Birds, and
Fifhes, at fome particular Seafons j Flies, Bees,
Earwigs, Spiders, and many other Infeds,
are fometimes in like Manner peflered with
them : nay, even the nimble Flea which
tpzes us and fucks our Blood, is not free
itfelf from Blood-fuckers, which harbour
very conveniently under the Scales of its
Neck, and about its Legs and Belly, cling-
ing too fall to be fhaken off. We are obliged
to Seignior Redi for the Figures of the Pedi-
culi peculiar to feveral Kinds of Beafls and
Birds; but I fuppofe he had no Opportunity
of obferving that of the Bat, which I am now
going to defcribe.

The little Animal which the Reader is
direded to take Notice of, at the Letters E,
F, G, Plate XV, was found adhering firmly

to the filmy Wing of a Bat then but newly
dead, and is undoubtedly the Vermin of that
Creature : many others were probably con-
cealed under its fhort thick Hair, but being
intent on examining this with the Micro-
fcope, and making Drawings of it, I omitted
fearching after more.

Its Body is nearly circular, and about the
30th Part of an Inch in Diameter. It is fur-
nifhed with eight Legs, each having fix
Joints: the lafl Joint terminates in a tranf-
parent Tuft or Ball, like thofe at the Feet of
fome Flies, but much larger and more fpread-
ing in Proportion to its Size, whereby it is
enabled to fallen itfelf ftrongly to whatever
it ftands upon. Two fmall Antennas or
Feelers are placed at the anterior, and a fmall
Procefs or Tail at the pofterior Part of this
Animal. A periftaltic Motion, or rather a
Contradlion and Dilatation, are alternately
carried on through the Inteftines, which ap-
pear more opake than the Parts about them,
and fomewhat in the Shape of the Letter
X.

This Animal is fhewn in its natural walk-
ing Pofture, with its Back uppermoft, at E,
and again at F with its Back downwards, and
its Belly next the Eye. It lived more than
twenty-four Hours between two Talcs, and
died nearly in the Pofture ftiewn at E, F, as
^t ftill continues in the Slider now before me.

As the Bat is extremely fwift in its Flights
and Returns, it was requifite the Vermin
living on it fhould have fome extraordi-
nary Power of preventing its being thrown
off; and accordingly this little Infed is not
only provided with larger Tufts or Balls than
ufual at the Extremities of its Feet, but has
alfo another very remarkable and uncom-
mon Means of preferving its Situation : for
on any fudden Emergency, infiiead of walk-
ing on its eight Legs, as it ufually does, it
can, in an Inflant, turn four, fix, or all of
them occafionally, fo far backwards as to
catch hold of any Thing, and walk on them
with its Back as eafily as with its Belly down-
wards ; and I often obferved it with four Legs
an their right Pofition, and the other four
ereded over its Back, and ready to lay hold,
as at G. Hereby it is enabled to fhift its
Pofture inftantly, yetflillmaintain its Ground
notwithftanding the fwifteft Motions, as I
had the Pleafure of experiencing in feveral
Attempts to jerk it off from a Quill, from
my Finger, and from other Things it fixed
itfelf upon, which all my Endeavours could
pot effed.nbsp;r

A V IN G received a Spider from the
Ifland of Nevis of a larger Size than
Ï had ever feen, I pleafed myfelf with the
Hope of obtaining thereby a better Know-
ledge of Spiders iû general than I poffibly
could by the niceft Examination of the
fmaller Kinds.

On meafuring it pretty exadlly, the Length
ofits Body andTail was found to be Inches;
the Breadth of the Body and the wideft Part
of the Tail very near an Inch. It had ten
Legs, of Vv^hich the foremofl two were fhort-
er than the reft, but the other eight were
each three Inches long at leaft, and in their
thickeft Parts a Quarter of an Inch Dia-
meter. Such were the Dimenfions when
dried, and confequently much fhrunk and
leffened : when alive it probably appeared
nearly twice as big. The whole Body and
Limbs were thickly covered with long Hair.
The Body was of a brown Colour ; the Tail
was alfo brovv'n, except one longitudinal in-
dented Stripe tif white, which paffed along
its Middle from where it joins the Body to
the Arms. The Termination of each Leg
was a curious Tuft of long foft Hairs, under

which lay concealed a Couple of exceeding
fharp hooked Claws, which muft be greatly
ferviceable in clambering, to cling to any
Thing, or to feize the Prey.

The Body was cruftaceous, having a Shell
as hard as that of a fmall Crab; the Tail Part
was foft and downy : on the Back both of
the Body and Tail the Hairs were fliorter
than elfewhere. The two Fangs were ftrong,
black, hard and horny, terminating and be-
ing Parts of two fliort thick Limbs to which
they were articulated, projedting from the
Body direftly before the Mouth. One of
thefe Fangs magnified about three Times is
ftiewn at Letter I. They were not placed
horizontally like a Pair of Forceps, fitted to
catch and hold Things by bringing their
Points to meet, as in moft of ourEnglifli Spi-
ders ; but they lay Side by Side, with their
Points bending downwards, and in Readinefs
to ftrike either fingly or together, after the
Manner of the Tarantula. Thefe deadly
Weapons of the Spider I was very induftri-
ous to examine, and by my Glaffes could
difcern very diftindly a minute Opening or
Slit near the Extremity of each Fang jufl in
the Front thereof, through which one can
hardly doubt a poifonous Juice was ready
(when the Creature was alive) to be ejedled
into the Wounds it made. This Aperture is
defcribed by Mr. Leeuwenhoek, in the 272d

Number of the Phil. Tranf. page 868 * :
but Dr. Meadh^v'ixig examined the Weapons
of feveral Spiders, and particularly of one
very large, without finding it, was inchnable
to believe, when he publiflied his curious
Account of Poifons, that Mr. Leeuwenhoek
had been miftaken, and that the Fangs were
capable of inflifting a Wound only into
which a poifonous Liquor was inftilled af-
terwards by a ftiort white Probofcis thruft
out of the Spider's Mouth -f*. Having alfo
never feen it myfelf at the Time I wrote my
Treatife on the Microfcope, I was then of the
fam.e Opinion. But as foon as I made the
above Difcovery, which was in April 1746,
I ftiewed the Fangs I have been defcribing
to Dr. Mead, who was much pleafed with a
Sight of this Aperture, and with his ufual
Candor gave it as his Opinion, that as amongft
Serpents fome Kinds only are poifonous, and
have Teeth that are perforated for the Emif-
fion of their Poifon, wa. the Rattle Snake,
the Viper, 6cc. whereas the Generality are
harmlefs, and have no hollow Teeth : fo
likewife fome Kinds only of Spiders are poi-
fonous, or have any Perforation in their
Fangs ; but fuch whofe Fangs are perfo-
rated may be fuppofed uncommonly dan-
gerous.

* See alfo Arc. Natur. Tom. IV. Par. II. pag. 39.
•J- Vid. Mecbanical Account of Poifons, third Edit./a^« 88.

It would not be ftridly honeft to pafs over
this Subjedt, without declaring, in Juftice to
the Memory of Mr. Leeuwenhoek, that not-
withftanding I have fometimes thought him
miftaken in his Defcriptions of Things exa-
mined by the Microfcope, it has feldom hap-
pened, but that afterwards I have found fuch
his Defcriptions true, and that the Objedls I
had formerly judged from were not exadtly
of the fame Sort, or in the fame Perfedtion
as his : And this I hope will make others
cautious, not immediately to determine in
Matters of this Nature from a ftngle and per-
haps a flight Examination; which I believe
too often has been the Cafe.

Having fatisfied myfelf concerning the
Fangs of this Spider, I proceeded to an Ex-
amination of its Eyes, which I found to be
eight, fituated on the Summit of the anterior
Part of the Body : for I think a Spider can-
not properly be faid to have any Head. I
?ut out a Portion of the Shell or Cruft in
which the Eyes were placed, that I might
bring them with more Convenience to my
Glaffes. And I foon faw that the two Mid-
dle Eyes were much larger and more re-
markable than the reft, and feemed exadlly
round, and that the three fmall ones on ei-
ther Side were oval. The Difpofition, pro-
portionable Size, and Appearance of them all
together, may be feen at PI,

After clearing away from the inner Part
of the Shell the Blood Velfels and other In-
teguments of the Retina, or perhaps the
Brain, the two larger Eyes (which were each
as big as a middling Pin's Head) appeared to
be tranfparent fpherical Bodies of an Amber
Colour. Part of each Sphere projefted ex-
ternally beyond its Socket, but the largeft
Part was funk internally within it, and there
was round each a circular tranfparent Mem-
brane by which it feemed to be faftened

The Figm-e and Tranfparency of thefe
Eyes raifed in me a Defxre to fee with the
Eye of a Spider ; and therefore cutting them
out very carefully (for in their natural Si-
tuation they could not anfwer my Purpofe)
I took the Pains to fet each of them in a

• Spiders Eyes are not pearled or compofed of fmaller Eyes
like thofe of Flies, Beetles, and moft Kinds of Infefts : they
refemble more the Eyes of Quadrupeds, but are not moveable,
which is probably-the Reafon why Providence has furniflied
the Spider with more Eyes than Infeds that have Eyes pearl-
ed, or Animals whofe Eyes can turn : for as Safety requires
that Creatures fliould be able to difcover Danger, or even
their Food, on whatever Side it lies, fome have pearled Eyes,
or more properly Clufters of Eyes, which (tho' not move-
able) are direaed every Way : the Eyes of others are as it
were multiplied by Motion ; but Eyes like thofe of the Spi-
der, and immoveable, would be unable to anfwer thefe Pur-
. pofes, unlefs there were more than two.

Indeed the Shepherd Spider has two Eyes and no more:
but then its Legs are fo very lotig, its Body fo fmall, and
thofe Eyes are placed in the Middle of its Back on fuch aa
Eminence, and in fuch aDireSion, that they take in nearly
a whole Circle. A fuller Account of this Spider, and Figure
cf its Eyes, may be feen in Dr. Hook's Micrographia.

Pin-Hole made through a Piece of Card,
whereby I could employ them to view Ob-
jedts with. Their magnifying Power was
very great, and had they been taken from a
Spider newly dead, I have Reafon to believe
they would have given me much Pleafure :
hut having been drying for fome Years, they
had contradled a Cloudinefs that prevented
Objedls being feen through them with any
tolerable Diftindlnefs. I am not however
without Hopes of bringing this Experiment
fome Time or other to fucceed, even with
our Englijh Spiders.

The wounding Inftruments of moft Ani-
mals, whofe Bite or Sting is poifonous, re-
femble in their Contrivance the Fangs of
the Spider juft now defcribed ; as will be
eafily comprehended by viewing the Tooth
of a Viper, pidured in the fame Plate at L j
wherein a fimilar Opening is ftiewn, through
which, on biting, a poifonous Juice is thrown
into the Wound j and alfo by the Fang of
an Indian Scolopendra or Millepes, near whofe
Point there appears a like Opening, ferving
to the fame Purpofe, at the End of a long
Slit or Fiflure, as may be feen at K. The
quot;Weapon with which the Scorpion ftrikes has
likewife fuch an Aperture.

Having defcribed all the Figures given
in the preceding Plates, I fhall add
a few Obfervations in a mifcellaneous Man-
ner.

In the Waters of fome Ditches there is
found a very fmall Sort of Leech, of a pale
brown Colour, whofe Length is about half an
Inch when extended fully. Several Months
in the Year its young ones are carried about
with it wherever it goes, flicking ifaft un-
derneath its Belly. Their Number is ufually
8, lo, or 12; and if feparated from the Pa-
rent, even to fome Diftance, they immedi-
ately replace themfelves, and that fo regu-
larly, they might eafily be miftaken for Legs,
whilft they are ftretching themfelves out
beyond its Body, with their Heads moving
to and fro, which is their conftant Pofture
when the Parent Animal is in Motion. This
Subjedl deferves farther Examination.

Curious Cafes are made by a fmall Worm
or Maggot, with admirable Dexterity, of the
Stalks of Duckweed, which the little Crea-
ture bites afunder with its Pincers, places
with great Order and Exaclnefs like the
Threads of a Linen Cloth, and glews toge-
ther. 'Tis diverting to fee the brifk Inhabi-
tant come a little Way out of its Door, ei-
ther for Food or Pleaftire, and immedi-
ately

ately, on the Apprehenhon of Danger, pop
in again, leaving nothing to be feen but a
few green Stalks.

In the Spring of the Year I have feveral
Times obferved great Numbers of little
Cafes, on a Row of Pales by the Side of the
New River at Enfield, made in the prettieft
Manner imaginable of the green microfcopic
Mofs growing on the fame Pales. They
were open at both Ends, and about a Quarter
of an Inch in Length : each contained a
little black, Maggot, that put out its Head
or Tail occalionally, and became at laft a
fmall black Fly.

Amongft the Eels in Vinegar one fhall
fometimes find accidentally a pretty and fur-
prizing Phsenomenon, i. e. a Chain, or Series
of minute Globules feemingly ftrung toge-
ther like a Necklace of Beads. Thefe are
nothing more than a Row of Air Bubbles
lying one behind another in the dead Body
of bne of the Anguillawhich Body from
its great Tranfparency is not vifible, unlefs
by the greateft Magnifier.

My good Friend Dr. Miles happening to
take Notice of a bright green Mouldings on
the Bark of fome Fire-wood : and, by a Lena
of an Inch Focus, finding it to beNumbers of
minute Fungi of a regular Appearance, he
employed a large Magnifier, through which
their fpherical Heads feemed as if they were
elfe but Globules of Seeds. He

obfervedj at the fame Time, feveral Seeds ad-
hering to the tranfparent Foot-Stalks which
fupported the Heads, and many fcattered on
the Glafs Plate whereon the Subftance was
placed for View ; whereby he had an Op-
Dortunity of feeing manydiftinâ: Seeds, near-
y of an oval Form, but feveral Times larger
than the Seeds of common Mujhroems, even
when feen with the fécond Magnifier, and
the latter with the firft.—He fays, he has of-
ten viewed the Heads of a I'mall Kind of
coriaceous Fungus of about 4- Inch Diame-
ter, and always found the Seeds on their
Gills much larger than thofe of any other
Muftiroom he had examined, tho' rather lefs
than thofe this unregarded Plant produces.

He fent with this Account a Piece of Wood
with the Mouldinefs thereon, and alfo fome
of it on a Slip of Glafs : both which I exa-
mined carefuHy to determine the Bignefs of
the Heads and their Seeds : and viewing the
Spherical Heads of the middle Size, (fome
being larger and others fmaller) I found,
(according to my Micrometer) that 3 of them
took up the Side of a Square, 70 of which
Squares made an Inch in Length : confe-
quently thrice 70, or 9,10 of thek Fungi,
make a Line of one Inch : or, in other
W ords, the Diameter of ûie{efungous Bodies
is, at a Medium, the 210th Part of an Inch.

The Seeds are oval ; and I find, by the
fame Micrometer, that i o of them laid by one

another the fliorteft Way of their Diametery
or S of them the longeft Way, fill up the Side
of a Square, 270 of which Squares make an
Inch in Length.—Taking therefore 9 as the
Medium, 270 Times 9, or 2430 of thefe
Seeds will be required to make a Line of an
Inch in Length •, or in other Words, each
Seed is the 2430th Part of an Inch in Dia-
meter.—And according to thefe Calcula-
tions 44100 of the Spherical Heads, or
5,904,900 of their Seeds, may lie by one
another in the Surface of an Inch fquare.

Yet minute as the Seeds of this \\tt\amp; Fun-
gus are, the Doftor obferves very juftly, that
they are bigger than thofe of fome others,
of the fame Genus which exceed it Thou-
fands of Times in Bulk. For the Seeds of a
very large edible Mufiroom being examined,
by a Glafs magnifying 320 Times in Diame-
ter, and their Figure being elliptical, 7 of
their longeft and 8 of their fhortefl; Diame-
ters were found equal to the Length of a
.Line known to be the 500th Part of an Inch.
So that the longeft Diameter of each Seed
was the 3500th, and the fhorteft the 4000th
Part of one Inch in Length, and 14,000,000
of fuch Seeds- would be required to cover
a Surface of one Inch fquare

• All the Species of Fungi were formerly fuppofed to bear
no Seeds Raj fays of them, nuHo nec Semine nec Flore ; but
good GlalTes now convince us of their producing Seeds in
vaft Abundance, growing commonly between the Gills.

T\\amp;proportionable Size of Fruits and Seeds
to the Trees and Plants that bear them,
comes under no Rules that correfpond with
our Conceptions. The Beech and AJh are
produced from Seeds fmaller than the Gar-
den Bean. The Oak has for its Fruit only a
fmall Acorn ; whereas the Pumpkin, whofe
Weight fometimes exceeds loolb. is the
Produdion of a feeble creeping Plant, un-
able to fupport itfelf, much lefs its enor-
mous Fruit. The Vanilla, (climbing to the
Height of feveral Feet) produces in long Pods
Seeds fo fmall, their Diameter is not more
than the looth Part of an Inch. Then fup-
pofing the Cavity of its Pod equal to a cy-
lindrical Tube of ^^ Inch Diameter, and its
Length to be fix Inches, (which Dimen-
fions are taken with great Moderation) the
Number of Seeds in one fingle Pod will be

I could add many more Obfervations,
which perhaps fome of my Readers might
be pleafed with j but finding this Work has
grown under my Hands, much beyond the
Size 1 intended, I fhali haften to conclude
this Part with recommending the Study of
Nature to all who have Leifure and Oppor-
tunity for it, as affording the mofc reafpnquot;-
ble Pleafure the Mind of Man is capable of
enjoying,

own Finger has defcribed himfelf. Hitman
Writings confiftof Linesznd Figures intend-
ed to denote the Sounds ox IVords of Lan-
guage,- which being at firft arbitrarily ap-
plied, were afterwards by common Confent
and Cuftom allowed to reprefent certain
Ideas, tho' without any Refemblance to them.
And as very different Sounds and Marks have
been employed, by Nations Strangers to each
other, to exprefs and denote the fame ObjeBs
qfthe Senfes or Conceptions of the Mind, hence
arofe different Languages and CharaBers,
which muft therefore be unintelligible to
all who have not previoufty been inftru6l-
ed in their Signification and Ufe ; nor can
be attained without a great deal of Pains zxA
Attention. But the Book of Nature is writ-
ten in an univerfaland real CharaBer, which
every Man may read in his own Language;
for it confifts not of Words but Things, which
pidure out the Perfedions of the Deity.
The ftarry Firmament every where expand-
ed, with its numberlefs Syftems of Suns,
and their furrounding Planets, the Regiila-
rity, Harmony, Order, and Conftancy of
their Motions, declare the Immenfity and
Magnificence, the Power and Wifdom of
their Creator. Thunder, Lightening, Tem-
pelts. Hurricanes, Earthquakes, and Vol-
canos, ftievv the Terror and Deftru6tion of
his Wrath» Seafonable Rains, Sunftiine, and
plenteous Harvefts, denote his Bounty and

Goodnefs, and his Regard for the Happine£s
of all his Creatures; and demonftrate how,
when his Hand is open, he fills all Things
living with Plenteoufnefs. The conftant
Succeflion of Generations in Plants and
Animals, implies the Eternity of their firft
Caufe. Life every where fuhfifting in Mil-
lions of different Forms, fhews the bound-
lefs Diffufion of his Animating Power; and
Death the infinite Difproportion between
him and every living Thing.—Even the
Adtions of Animals are an eloquent and pathe-
tic Language; thofe that want the Help of
Man, have a thoufand engaging Ways,which
like the Voice of God fpeaking to his Heart,
command him to preferve and cherifli them }
whilft the Looks and Motions of fuch as
would do him Harm, ftrike him with Ter-
ror, and warn him to fly from or arm him-
felf againft them. In fhort, every Part of
Nature diredts us to Nature's GOD; for ac-
cording to Lucan, iq that fine Speech he
makes for Cato,

Ecme Account of a new-confiruEied Microfcopc,
ufed in the foregoing Experiments.

' ■ ^ H E cumberfome and inconvenient
Double Microscopes of Dr. i^oci
and Mr. Marjhai, were many Years ago re-
duced to a manageable Size, improved in their
Strudture, fupplied with an ealy Way of en-
lightening Objefts by a Speculum under-
neath and in many other Refpefts render-
ed agreeable to the Curious, by Mr. Culpep-
i)er and Mr. Scarlet. Some farther Altera-
tions were hov/ever wanted to make this In-
ftrument of more general Ufe, as I fully ex-
perienced in the Year 1743, v/hen examin-
ing daily the Configurations of Saline Sub-
ftances, the Legs were continual Impedi-
ments to my turning about the Slips of Glafs;
and indeed I had found them frequently fo
on other Occafions. Pulling the Body of
the Inftrument up and down was likewife
fubjedt to Jerks, which caufed a Difficulty in
fixing it exadly at the Focus : there was al-
fo no good Contrivance for viewing opake
Objeds. Complaining of thefe Inconvenien-
cies, Mr Cuf, the Optician, applied his
Thoughts to fafhion a Microfcope in another
Manner, leaving the Stage entirely free and
open by taking away the Legs, applying

fine-threaded Screw to regulate and adjuft
its Motions, and adding a concave Speculum
for Objeds that are opake.

The foregoing Examinations having been
all made by an Inftrument thus improved, I
fhall give a Plate and Defcription of it, (as
an Addition to my former Book on the Mi-
crofcope) by the Name of Mr. Cufs tiew-
conJiruSted Double Microfcope.

All Parts of this Inftrument are Brafs.—
The Body A, being firmly fupported in a
broad circular Collar at the End of the Arm
lt;i a, which projeds from the Top of the
Pillar C, may be taken out or put in at Plea-

A fquare Box b b, fere wed down to the
wooden Pedeftal II, fupports the whole Ma-
chine, by the Afiiftance of the long flat-
fquare Pillar B, which is fixt within the faid
Box.

The moveable Pillar C, which is fhorter
than the Pillar B, tho' of the fame Shape, by
Aiding up or down againft the broad flat
Side of the faid Pillar, raifes or lowers the
Body of the Microfcope as Occafion may re-
quire.—Both Pillars ftand in the Box b b.

The fquare Collar D holds the two Pillars
B and C together, and flides up or down
upon them, carrying with it the Body of the
Microfcope.-The Screw-Button 3 is in-
tended to fix the Pillar C, when the upper
Edge of the Collar D being fet at the fame

Number as that of the Magnifier employed,
its focal Diftance is brought nearly right.

When the Pillar C is faftened, the Mi-
crofcope (by the fine-threaded adjufting
Screw E) may be moved fo gently up oi'
down, v^'ithout Jerks or Slips, that the true
Focus may be found with great Readinefs
and Exadnefs.

The horizontal Plate or Stage F, having
in the Middle thereof a circular Hole 4, di-
redly over which the Body of the Micro-
fcope is fufpended, is exceedingly convenient
to place Objefts on for Obfervation, being
freed intirely from the Legs which incumber
other Double Microfcopes.

The concave Looking-Glafs G, turning
en two fmall Screws in the Arch d (at the
Bottom of which a Pin goes down into the
Hole e in the Pedeftal) refieds the Light of
a Candle or the Sky diredly upwards on the
Objed, by moving the Looking-Glafs hori-
zontally or vertically.

A double convex Lens H, turns on two
Screws, for tranfmitting Light to afiift in
illuminating opake Objeds, when the long
round Wire ƒ is placed in the Spring-Tube
g, at the Corner of the Stage F.

I—is a hollow Cylinder whofe Sides are
open, and at whofe End a concave Silver
Speculum h, having a round Hole in the
Midft thereof, is fcrewed. This Cylinder
flips over the Snout / of the Microfcope, and

when fet to the Figure there marked, and
correfpondent to the Number of the Mag-
nliier made ufe of, the Silver Speculum re-
fleds Light on the opake Objed to be exa-
mined; which Objed muft either he held
in the Spring-Tongs at one End of the Wire
C, placed in the Slit m on the Stage F; or be
put on the Ivory Block P, ftuck on the point-
ed End of the laid Wire. The third or
fourth Magnifiers are fitteft to be ufed with
the Silver Speculum.

K. L. M. N. Q^Q^R. S, T. V. W.X, Y.
Z. are different Parts of the Apparatus which
I think needlefs to defcribe, as all who are
acquainted with Microfcopes will know them
at firft Sight, and others may inform them-
felves either in my former Treatife on thefe
Subjeds, or in the Book which Mr. Cujf
gives to thofe who buy this Microfcope of
him.

In the Year 1747 a Micrometer for this
Inftrument was alfo contrived by Mr. Cuff,
being a Lattice of fine Wires, placed (when
made ufe of) in the Focus of the Eye-Glafs,
by unfcrewing the Body of the Inftrument,
As the Readinefs wherewith the real Size of
Objeds may be calculated by thjs Microme-
ter muft render it valuable to the Curious,
there needs no Apology for laying fome
Account of it before them, drawn up and
given to me by my much honoured Friend
^artin Folkes, Efq; Prefident of the Royal

Societyf and firft Prefident, under the Royal
Charter, of the Society of Antiquaries of
London

Remarks Qn (i Micrometer to be applied tn
compound Microfcopes. By Mar-
tin Folkes, Efq; P. R. S.

TH I S Microm^eter only confifts of 3
Lattice of fine Silver Wire diftant
from each other one fiftieth Part of an Inch,
interfering at right Angles, and fo placed
In the Focus of the Eye Glafs, as to divide
the whole vifible Area of the Microfcope in-
to Squares, whofe Sides are each the -yVth of
an Inch.

Now as the Image of any Object to be ex-
amined is formed in this Place, it is plain that
by this Lattice Work fuch Image may readi-
ly be meafured, either by comparing its
Length or Breadth with the Diftance of

* This Gentleman, whofe amiable Charader for Ability in
Science and Goodnefs of Heart is known and refpefted by '
all the World, being unhappily difabled by a paralytic Dis-
order fiom attending the Meetings of the Royal Society, where
for eleven Years he had prefided with great Honour, thought
jfiper on the laft annual Day cf Eleilion, viz. November
50th 1752. to decline being again elcdled Prefident. Where-
fore the Gentlemen of the faid Society, after returning their
moft grateful Acknowledgments to Mr. Folkes for his many
and ufeful Services, elefted unanimou/ly the Right Honour-
able Earl oi Macclesjidd to bs their Pijesident in his
Stead.

the Wires; or by comparing its whole vifi-
ble Superficies with one or more of the lit-
tle Squares formed by the InterfecSion of
the fame Wires.

And the true Size of the magnified Image
being thus known, the true Magnitude of
the Obje6l itfelf will be known alfo, if the
magnifying Power of the Objed: Glafs is but
given : and this will eafily be found in the
following pradical Manner :

Let a minute Objed of a known Size, be
carefully viewed in the Microfcope: as for
Example, Part of a fine diagonal Scale divid-
ed into the Millefimals of an Inch; and let it
be examined how many of thofe Millefimals
anfwer to the Diftance of two of the Wires
abovementioned, remembering to eftimate-
that Diftance from the Outfide of one of
the Wires to the Infide of the other. For
as 20 are to that Number of Millefimals jufl:
found, fo is the Length or Breadth of any
Image meafured by the Micrometer to the
Length or Breadth of the Objed itfelf: or as
400 are to the Square of the fame Number
of Millefimals, fo is the .magnified Superfi-
cies of any Image, to the true fimilar Super-
ficies of the Objed.

And again, as that Number of Millefimals
of an Inch juft found is to 20, fo is Unity to
a Number exprefllng how many Times the
Length or Breadth of any Image eftimated
by the Micrometer, is greater than the true

Length or Breadth of the Objedt itfelf: and
this laft Number I call the magnifying Power
€f the Objed Glafs.

This Trial is to be made with Care once
for all, for every different Objed Glafs to be
ufed with the Micrometer : and their dif-
ferent refulting magnifying Powers, once re-
giftered in a Table, will be ready upon all
Occafions. For thus the Length or Breadth
of any Image eftimated by the Micrometer,
will v/hen divided by the magnifying Power
of the Objeft Glafs, exprefs the true Length
or Breadth of the Objed itfelf: or the Su-
perficies of any Image eftimated by the Mi-
crometer, in fquare Millefimals of an Inch,
will in like Manner exprefs the true fimilar
Superficies of the Objed itfelf j if it is divided
by the Square of the magnifying Power of
the Objed Glafs ufed. And for this Purpofe
it may be of Ufe to fet down in another Co-
lumn of the Table, the refpedive Squares
of the Numbers exprefiing the magnify-
ing Powers of the feveral difterent Objed
GJjffes.

As fome Difiiculty may be found, in ap-
plying the diagonal Scale abovementioned to
the larger Magnifiers : chiefly thro' want of
Light when the Objed is to be brought very
near to the Glafs; that Defcd may be fup-
plied by the Ufe of fome minute natural Ob-
jpft, whofe true Size has already been care-^
folly determined by one of the leflTer Magni-

fiers, and whofe Image is again viewed with
one of the greater: for as the Number of
Millefimals of an Inch contained in its true
Length or Breadth, are to thofe now found
in the Length or Breadth of its Image, fo
will Unity be to the magnifying Power of
the Objedt Glafs now made ufe of, amp;c.

I fliould now farther take Notice, that
the Numbers here called the magnifying
Powers of the feveral Objed Glalfes, do not
exprefs the whole m?gt;gnifying Power of the
Microfcope. For the Image formed in the
Focus of the Eye Glafs is again magnified
to the Eye, by the Operation of the Eye Glafs
itfelf. And the Focus of this Eye Glafs be-
ing, in the Double compound Microfcope
made by Mr. Cuf, and which he calls (tho'
fomewhat improperly) his new double rejleSi-
ing Microfcope, at the Diftance of one Inch
and a Quarter nearly j the Eye, placed on the
other Side, views the Image of any Objed
formed in that Focus under ap Angle about
feven Times as great as that under which it
would fee it with Diftindtnefs if naked, and
at the Diftance of fomewhat lefs than nine ^
Inches. We may therefore then confider all
Images viewed with this Microfcope as mag-
nified feven Times in Length or Breadth, or
49 Times in Superficies by the Intervention
of the Eye Glafs: and we may confequently
exprefs the whole magnifying Powers of the
Microfcope, if we refpedtively multiply the

I would juft obferve, that fome Double
Microfcopes have aDrawer between the Glaf-
fes, and by Means of which they magnify
differently with the fame Glafs: in thefe Mi-
crofcopes therefore one Pofition of the Drawer
Ihould be pitched upon as the moft conve-
nient, and the fame ihould conftantly be ufed
whenever any Magnitude is to be determined
by the Micrometer applied to the fame.

The Lattice abovementioned, whofe Wires
are only diftant a Fiftieth of an Inch, may up-
on fome Occafions be found inconvenient in
viewing of Objedts. But it may very eafily
be taken out and put in occafionally, or have
its Place fupplied by another whofe Wires
may be the 20th or the loth of an Inch
afunderj and this laft efpecially will give no
Hindrance to common Obfervations, and will
befides be very ufeful to fuch as would draw
with fome Exaftnefs any of the Objedts
they examine with their Microfcope.

I am told that Silver Wire may be had to
make thefe Lattices of, whofe Diameter is
rather lefs than the feven hundredth Part of
an Inch.

The Mention Mr. Folkes makes of a Lat-
tice whofe Divifions are -V of an Inch, was
owing to his having experienced the Utility
of fuch an one in my Microfcope, made by
myfelf of human Hairs, and faftened exadlly

in the Focus of the Eye Glafs, whofe Dif-
tance being 11 Inch, or x-s-ths of nine Inches,
(the Standard of Sight he computes by
the Diameter of an Objedl feen through that
Glafs is magnified 7 Times, and the Side of
each Square whofe real Length is appears
(magnified through the faid Glafs) to be
-rVths of an Inch.

Employing different Objedt Glaffes or
Magnifiers in viewing Objeds, makes no Dif-
ference in the Lattice or Micrometer, whofe
Squares are magnified by the Eye Glafs only,
and always appear of the fame Diameter,
that is, Ti^j-ths of an Inch. But the Objed
being more or lefs magnified according to
the Power of the Objed Glafs, the Image
thereof thrown upon theLattice extends over
more or fewer of its Squares : whence the
magnifying Power of all the Glaffes belong-
ing to my Microfcope,^and the real Size of
Objeds examined by them, are fhewn in
the following Table.

• The ufual Standard of Sight is 8 Inches, but as Mr.
Fjilkes has thought proper to make it almoft 9 Inches, all thefe
Calculations are conformable thereto.

A T A B L E of the magni^ng Po-wers of the Glaffes belonging to my own Double tompmndUimfcope, together
with the Meafure of a fingle Square of the Micrometer compofed of Tenths of an Inch, when any one of the
Glaffes is employed ; according to the foregoing Method of Calculation.

— u I

sa: s

O agt;

l-'l-s

lt; 2 o quot;

2 s.y s

320

quot;189
i6i

49
28

L i7i J

= H
M s

a i-i
E îe
rt «
u. 3

ir quot;S
« V
Al

s 00

60 B
rt 4)

« .s
■s-g

Ph U J

The Magnifiers are diftinguilhed in the firft Column by the Nquot; i, 2, 3, amp;c.
The fécond Column Ihews how many Times each Glafs magnifies the Diameter of any Objefl.
The third Column fluews how many Times each Glafs magnifies the Superfieies of any Objea.
The fourth Column determines the true Length of any Ôbjeft, by ftewing what Part of the Length of an Inch
fuch Objed really is, when, viewed by either of the Glaffes, it appears the Length of one Square of the Micro-

The^fifth Column determines the true Size of any Objefl, by fhewing what Part of a Square Inch fuch Objeft
really is, when, viewed by either of the Glaffes, it fills up the Area of one Square of the Micrometer.

» This Glafs, whofs magnifying Power is extraordinary, was made particularly for me.

an Objeft, whofe Diameter when viewed
through the Magnifier i. appears the
exa£l Length of one Square of the Hair
Micrometer, is really no more than the 270th
Part of an Inch in Length.

And if, when viewed through the farne
Glafs, it appears to fill up the whole Space
of one of the faid Squares, its real Area is
no more than the 72900th Part of a Square
Inch, amp;c.

In order to render this Inftrument ftill
more ufeful. Squares may be drawn on Paper
(with very black Lines) correfpondent to
thofe of the Micrometer magnified by the
Eye Glafs, viz. -/s- ths of an Inch Diameter ;
by the Means whereof, (if placed under fo
thin a Paper as they can plainly be feen
through,) an Object may, be drawn exaftly
of the Size it appears when magnified by
any Glafs whatever.—^Nine Squares fo
drawn are ftiewn Rlate ILNW. fig. 6.

In the fame Plate,4 ftiews a Micro-
meter whofe Divifions are the Fiftieths, and
jig. 5, another whofe Divifions are the Tenths
of an Inch : And this laft may remain in
the Body of the Microfcope, without being
any Hindrance, whatever Glafs is ufed.

'Twere well if the Workmen ground,
their Glaftes fo exactly to a Standard, that
{he fame Table might ferve for the Micro-
meter to every Set of them j but as that is
' Vol. n.nbsp;Ffnbsp;not

Though Mr. Leeuwenhoek's Mi-
crofcopes are much talked of, very
few People are acquainted with their Struc-
ture and Apparatus, no Figure of them that
I remember having ever been made public:,
'tis therefore hoped the Curious will be pleaf-
ed to fee a Drawing of them, taken with
great Exadtnefs from thofe in the Repoflto-
ry of the Royal Society, which are all alike
in Form, and difter very little in Size from
this Drawing, or from one another

The two Sides of one of thefe Microfcopes
are ftiewn Plate XVII.7 and 8. The
Eye muft be applied to the Side/^. 7.—
The flat Part A is compofed of two thin
Silver Plates faftened together by little Ri-
vets h bh b b b. Between thefe Plates a very
fmall double-convex Glafs is let into a Socket,

* An accurate Defcription of the 26 Microfcopes, and
Objefts belofiging them, contained in a fmall Cabinet
which Mr. Leewwenhoek at his Deceafe bequeathed to the
-R^yal Society, was nrcfented many Years ago to that Society
by Martin Folkes. Efq; and may be feen N° 38(3 of the Phi-
lofophical Tranfaaions. And a farther Account, fetting forth
the magnifying Powers, and other Particulars concerning the
fame Micoicopes, (which were three Months under my Exa-
mination for that Purpofe) was prefented by me to the Rcyal
Sin'ay in-the Year 1740, and publiflied Phil. Tranf Nquot; 458-
But neither of thefe Accounts has any Drawing of the Ml-
..oicopes.nbsp;^^^

and a Hole drilled in each Plate for the
Eye to look through at c. A Limb of Silver
d is faftened to the Plates on this Side by a
Screw e which goes through them both.
Another Part of this Limb, joined to it
at right Angles, paffes under the Plates,
and comes out on the other Side; vid.
Jig. 8) at f: through this runs, diredt-
ly upwards, a long fine-threaded Screw
g, which turns in and'raifes or lowers the
Stage h, whereon a coarfe rugged Pin i for
the Objedl to be faftened to, is turned about
by a little Handle k ; and. this Stage with the
Pin upon it is removed farther from the
magnifying Lens, or admitted nearer to it,
by a little Screw /, that pafling through the
Stage horizontally, and bearing againft the
Back of the Inftrument, thrufts it farther off
when there is Occafion. The End of the
long Screw g comes out thro' the Stage at
m, where it turns round, but adls not there
as a Screw, having no Threads that reach
fo high.

Thefe Microfcopes are plain and fimple
in their Contrivance. All the Parts are Sil-
ver, faftiioned by Mr. Leeuwenhoek'^ own
Hand, and the Glafies, which arc excel-
lent, were all ground and fet by himfelf. He
glewedoneoratmofttwoObjedlson the Point
of the Pin belonging to each Microfcope, and
carefully preferved them there j fo that each
Inftrument being devoted to one or two Ob-
E f 2nbsp;jedls

jefts only, could be applied to nothing elfe.
This Method induced him to make a Mi-
crofcope with a Glafs adapted to almoft eve-
ry Objed:, 'till he had got fome Hundreds of
them, as he fays himfelf, in the 2d Vol. of his
Works, page 290, Mthi quidem funt centum
centumque Microfcopia, See. All this Trouble
and Expence is now faved, by a Set of Glaf-
fes to be ftiifted with great Eafe, as the Sub-
jed to be examined may require.

The magnifying Powers of thefe Glaftes
come ftiort of fome now made, but are fully
fufiicient for moft Purpofes. Of the 26
Microfcopes I examined, one magnifies the
Piameter of an Objed 160, one 133, one
114, three 100, three 89, eight 80, two 72,
three 66, two 57, one 53, and one 40
Times.

Direâllons for obtaining an exa5l Reprefent a'
tion or PiBure of any Coi-i^ or Medal.

in the fineft Sealing Wax, cut the Wax
away round the Edges of the Imprefîion,
with the Point of a Penknife, or a Pair of
fliarp Sciffars.

The Rolling-Prefs Printers have an Ink for
printing oftquot; Copper Plates, very different
from what other Printers employ in print-
ing Books: work fome of this withauHair-

Pencil into all the Lettering and hollow
Places of the Wax Impreffion, which are
the rifingor projedling Parts of the Medal.
This done, pafs your bare Finger, or a Cloth
ilrained upon it, gently but nimbly over the
Surface, till you perceive the Ink perfedlly
cleared away, unlefs where the Letters are,
and in the finking Parts; and after this,
rubbing your Finger on a Piece of foft Whit-
ing, pafs it lightly over the Surface 'till you
are fure it is dry and clean.

Have ready, foaked in Water, but the
Water fqueezed a little out of them, fome
Pieces of Writing Paper fomewhat larger
than the Medal. Place one of thefe on the
Wax Impreflion and on the Back of the
Paper lay three or four Pieces of thick Flan-
nel about the Size thereof.

I (hould premife, that you muft have a
Couple of flat fmooth Iron Plates, about two
Inches Square, and of a Thicknefs not to
bend. The Wax Impreflion muft be placed,
with its Face upwards, on the Middle of one
of thefe Plates, before you fpread the Paper
and Flannels on it; and the other Plate muft
immediately be laid over them. Then, hold-
ing them all tight together, put them care-
fully and evenly into a little Prefs, made of
two Iron Planks about five Inches and a half
long, one Inch and a half wide, and half an
Inch in Thicknefs: having a Couple of male

Screws that run through them, with a turn-
ing female Screw on each to force the Planks
together. And thefe female Screws muft
have ftrong well-tempered Shoulders, where-
by to work them, A Figure of this Prefs is
ftiewn P/^/^ XV[I.9.

Things being thus adjufted, holding
the Prefs in your Left-Hand, ftrike wi.h a
little Hammer, firft on the Shoulders of one
Screw, and then on the Shoulders of the
other, to bring the Planks together parallel,
and render the Prefture every-where alike ;
unlefs you find it requifite to give more
Force to one Side than the other, which
thefe two Screws will put in your own
Pov/er.

The Prefs opens again, by a Stroke or two
of the Hammer, the contrary Way, on the
Shoulders of the Screws : and then you will
find a true and fair Pi6lure neatly printed
offquot; J which (if any Deficiencies appear there-
in) may be eafily repaired, when dry, with
a Pen and Ink, or, what is better, a Pencil
and Indian Ink.

This Method is very eafy and ready for
taking the Pidure of a Medal either in Black
or Red ; proper Ink of both which Colours
may be had of the Copper-Plate Printers :
but your Wax Impreftion muft be diff^erent
in Colour to that of the Ink you ufe, other-
wife you cannot fee when the Ink is well
cleared away j and as the whole Succefs de-
pends

pends on the Goodnefs of the Wax Impref-
fion or Mould, the following Rules, taught
by Experience, are recommended to be ob-
ferved.

1.nbsp;Let the Wax be fine, or it wants a
proper Hardnefs, and the ImprelTion
will not be lharp.

2.nbsp;Spread it wider than the Medal, and
of a Thicknefs in proportion to the
Relievo of it.

3.nbsp;Clap on the Medal when the Wax has
a moderate Degree of Heat: for, if it
be too hot, the Medal is apt to flick:
and, if too cold, no good Impreffion
can be taken. The right Time, feems
to be, juft after the Wax ceafes to work
up with little Bubbles in it.

4.nbsp;Make not the Impreffion on a Table
or any hard Body, without feveral Folds
of Paper, or, what is better, a Woollen
Cloth, or fome foft Leather underneath ;
for foft Things give Way to the Pref-
fure and Form of the Medal, which
hard Bodies will not do.

5.nbsp;Squeeze the Medal down equally hard
on every Side, and continue the Pref-
fure 'till the Wax is near cold : for if
the Medal be taken off while the Wax
remains hot, the rifing Parts, being ftill
foft, will fink down, and the Impreffion
be much lefs ftiarp,

6. White Paft^baard, Card-Paper, or
fome other thick Paper, is beft to take
Wax Impreflions on.

In Places where Copper-Plate Printer s
Ink cannot be had, Water-Colours may be
made ufe of. Lake and Vermilion mixt
make the moft proper Red, Indian Ink the
beft Black. Diredions for other Colours
may be feen, Phil Tranf. N° 472, p 82 ;
in an Account of this Invention laid by me
before the Royal Society Anno 1744, from
whence this is partly taken.

There are indeed many other ingenious
Contrivances for taking off Medals, in Sul-
phur, Plaifter of Paris, Paper, ^c. But fince
a Mould muft be formed for each of thefe,
either of Clay, Horn, Plaifter of Paris, or
fome other Materials, which requires a great
deal of Trouble and Time to form, this Me-
thod I believe will be judged abundantly
more convenient, efpecially as fome of thofe
Ways do really a great deal of Injury to Me-
dals, by impairing the Sharpnefs of their
moft delicate and expreflive Strokes.

For Wax is always ready, and hurts not
the fineft Medal: and however brittle it
may be thought, the Moulds made thereof
refift the Force of downright Preffure, al-
moft as effedlually as if they were made of
Steel; and might ferve to take off a thou-
fand Impreffions, were they not apt to crack,
and the Marks of thofe Cracks to render

what are taken from them afterwards not
quite fo elegant. But each Mould will ufual-
ly afford three or four good Impreffions, ei-
ther coloured or plain ; and if the Ink be
got off clean, the fame Wax may be melted
and employed feveral Times.

It is evident, that Impreffions taken thus,
muft be exadtly what the Medals are from
whence we take them, and that any Perfon
who can procure the Wax Impreffions of
Medals, may, by a little Pains, be furnifh-
ed with a noble Colkaion of the genuine
Prints of Medals; which may be placed in
Books, in orderly Series, and moved from
one Leaf to another at Pleafure; if a little
Margin be left about them, and only the
Edges be pafted down. I flatter myfelf
therefore, that the Ufefulnefs of this Con-
trivance will not be flighted, on account of
its being fo plain and obvious, that every
Gentleman will wonder he did not hit on it
himfelf; fmce Difcoveries that are moft eafy,
and confequently may be pradifed by every
body, however fimple and void of Inven-
tion they may appear, are really in them-
felves moft valuable. I need only inftance
the Art of Printing, (from which this in
fome Sort is borrowed) the moft happy
Difcovery that perhaps was ever made by
Man ; yet feemingly fo eafy, and what the
Ancients came fo near to in their Seals, that

In this Manner I have taken off many
Thoufands of Coins and Medals for myfelf
and Friends: and as any Gentleman may
divert himfelf by doing it, I hope this Ac-
count of it may prove acceptable.

As the lafl Tlate was not finifhed till the
whole Book was nearly printed off, whereby
fome Figures in it are not defcribed in their
proper Places : It may be needful to inform
the Reader, that N° I, II, III, are different
Branchings of Copper, produced by the fe-
veral Mixtures mentioned CHAP. LIII.
Part I.—That N°X, XI, are two Species
of Corallina marina, and XII a Species
of Fucus marinus, all magnified by the Mi-
crofcope.

produces Comet-like Figures — — — —nbsp;99
how to preferve — — — — — — —
how produced — — — — — — —
Earth from Africa — — — — ——

Infefts how fuppofed to get into it — —nbsp;HS
Ammoniac (Salt) defcribed — — — — — — '09

examined by the Microfcope — — —nbsp;I'o
renders Water cold — — — — —
Angnilla, vid. Eels.

with a Probofcis — — — — —nbsp;217
Antimony (Flowers of) defcribed and examined — — iz'
the Bafis of AV«»?^ _ _ _ _ —

Cafes of People poifoned by it — 132, 136-7
Experiments to know it —. — —
Fumes how pernicious — __ — ijj
gives a Silver Colour to Copper — — 135

AttraBion and Repulfion fuppofed greatly inftrumental in the
Configurations and Cryftals of Salts, amp;c. 27, 48
Alternate Fits of each — — 27,29
Queries concerning — — ,— 26, amp;c.

Bag-Antmal, or Pediculus Aquaticus
Banftickle, Or Prickle-hack, Loufe of —
Bark (Peruvian) examined —- —

Bell-Flo'wer Animal, or plumed Polype —
Animals — — — _
Benjamin, Flowers of — «—
Barbery, Salt of — — — —
Blandy, Mr. poifoned by Arfenic, his Cafe
Berax examined — —. —.

its Defcription and Ufe — —
native from Perfia — — —
Boxes and Phials for Solutions of Salts —
Branchings of Copper refembling thofe on
Dendritie, 8cc. how to produce — —
Brijiled In/ea —nbsp;— _

Candle-light beft to examine Salts by the Microfcope
Carduus (Salt of) examined — — —
Carp, Loufe of — — — — —
Ci^j-made of Duckweed by a Maggot — —

Mofs by a Maggot — ■—
Cheltenham Salt —- -— — — —
Cobalt, what — — — — —

Arfenic and Smalt made from it — •—
CalleBion of Solutions how to make and preferve 32,
Colours of precious Stones whence derived

178
374

416
149
128
ibid.

43, 82, 2i6
Co»'

not to Vegetation — 41
Gems formed in the fame Manner — 4^
Co//«»-Particles how attraaed by Iron 78, 8z, 196 to 208
obtained pure by fuch Attraftion — — 80
gives Colour to Gems - — — 82

according to Si» Ifaac Newton — — 2Z
how to preferve — — —
Cryftals, their very minute Figures the fame as when large

Deftgn of this Work —_ ——-— —
DireSions how to make Solutions of Salts —

Drawings how neceflary to thefe Subjeas — —
in thisWork no fanciful Reprefentations
Duckweed, curioas Cafes made of it by a Maggot

Experiments on them — —
their recovering Life — —257
of the Water Snail examined — — — 324
their Progreffion towards Perfedion

165
142

H3
302

383

160

I2C

223

33quot;
332

Pediculus Aquaticus, or Bag-Animal
Flowers of Benjamin —__ __ __ —
Antimonynbsp;— __

/■f^, its pretty Configurations — — —
Funnel-Animals, or Tunnel-like Polypi •— —
their Manner of multiplying ■

Globe Animal — — _ _ —
God, all things alike eafy to him — — — 229
Refledlions on his Works — —■ 230, 420

his Perfeftions taught us by every thing — ibid.
GuUeltninus his Obfervations on the Figures of Salts — 24

Harveji-Bug _ — — — —nbsp;393
Heat affifting in mott Operations of Nature — — 4, 13
how employed in thefe Experiments — — 13

Ink (good Writing) how to make — — — ■— 92
Sympathetic — — — — — '3?
ImpreJJlons of Medals to take off in Wax — — — 436
to print off in Colours — — 438

Leech carrying its Young under its Belly — —nbsp;4« J
Letter to Martin Folkes, Efq; concerning the Wheel Ani-

Jullice done to his Charafter — —nbsp;4'2
Life feemingly fufpended — — — -—254

43Ö

192

425

426
430
432

for his Experiments on Salts, amp;c.
Medals, how to take Is preffions and Piftures of
Metals., ^^egetation cf, what ■nbsp;——

ibid.
434

183

410

417

418
179

348

418

Mouldinefs on the Bark of Wood —
minute Fungi, of what Size
their Seeds
Mi/gnvort, Salt of — — —
Mulberry Inject — -■
Muproom, edible, its Seeds -- —

N/t-like Arms, an Infeft having fuch

j^itre or Salt-Pftreexzm\r\iA -

its Cryftals - -

how produced —— —
Obfervations on ■
Diffolvent of Silver -

Conjeftures concerning their Figures — 23, 26
of Cryftals, what Properties fuppofed to have 27
endued with a Kind of Polarity -— ihid.
of Salts give Figure to the regular foflil Bodies 213
Pediculus Aquaticus, or Bag-animal —— ■

hollow of S.ilt how formed — — — — 57
Pyriia: productquot; Vitriol--—-—* 86, 90

S^eries concerning the Formation of Cryftals and Configu-
rations ■ ■ -nbsp;------- 26, amp;c.

383

79
125

349

208

209
211
152

332
ibtd,
306
335
337-8
342

- 199

195, SiC.

- 391

- 208

— 184
ièid.

incorporated with Metals caufe Ramifications^ 214
Ohjeaior., t\izi their Figures cannot be determined, an-

their Solutions how to prepare and preferve — 10, 14
how to examine by the Microfcope 11

Saccharum Saiurni, Sugar or Salt of Lead

Salts in general what -- --

aft not but when dilTolved

-nbsp;56

gt;47

-nbsp;149

iso

-nbsp;152

-nbsp;153
155

158
162

-nbsp;168
170

-nbsp;171
172

'73
Worm-

firft noticed by Monf. Jci/o^ — —nbsp;3'?
Sfa ^iTa/^r luminous by Infefts — — —

Scolopendra luminous — — — —nbsp;4°'
Sherwood (Mr. James) his Difcovery as to Eels in Pafte 245

9
80
356

358

360

126
ibid.

Sqttilla, frefti Water — — — ~
Account of — — —
bow voracious — —
long fnouted — _ — —
Sublimate corrofive, defcribed and examined — —

vitriolatcd — — — — _nbsp;ijs
TincaU or Tilicar, i. e. rough Borax, v. Borax.

Oil of, how poifonous ■— — —■ 1/7
rranrmu.üiionoflron into Copper, what, and how eiFefted 79

Vanilla, its Seeds, how numerous — •
Vegetation, Terms of, how to be underftood in this
of Metals what — —gt; —
Silver . — — —.

its Configurations and Cryftals —
Vitriol in general — — ■— —
blue _ — — _ _
contains Copper — — —
green contains Ironnbsp;_ —

whence produced — —
how to prepare for the Microfcope
white contains Iran, Lead, or Tin —
Experiments with — —
Urine, SAt of — — — —

41ÇJ
Work 42
— 192

195 to 208

—nbsp;84
- 87

•13

302

351

436
266
292
29s

lt;The'^Vàte 0/the Mi - oßope, (tiuhich is not numbered) muß he
fut fronting Pa^e 422.








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