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yjPA^L.
THE
ELECT W O R K S
O F
ANTONY VAN LEEUWENHOEK,
CONTAINING HIS
MICROSCOPICAL DISCOFERIES
IN MANY OF THE WORKS OF NATURE.
TRANSLATED FROM THE DUTCH AND LATIN EDITIONS PUBLISHED EY THE AUTHOR,
By SAMUEL HOOLE.
VOLUME THE I'IRST— PART the FIRST.
Wanneerje fchoone dingen fiet,
Vergiept u aeii het fchcprd niet ;
Oock wilt daer op niet blyven flaen,
Macr laet uw' finnen verder gaeu ?
Ey klimt ! o licve, klimt om hoog,
En metten geell, en mettet oog,
En fiet, dat gy tot hem geiiaeckt;
Die al wat fchoon.is heeft gemaeckt.
yac. Cats iverhny tweede deelpag. 400, 'tDruk, ijiS.
Inde hominum pecudumque genus, vitseque volantum
Et quas marmoreo fert monftra fub aequore pontus.
V'lrg. /En. vi. 728, 729,
*' Lo, thefe are parts of his ways : but how
little a portion is heard of him ?
Job. xxvi. 14,
A
LONDON:
PRINTED FOR THE TRANSLATOR,
By G. SIDNEY, Black-Horse Court, Fleet-S.treet;
And fold by G. and W. Nicol, Bookfellers to his Majefty, Pall-Maii ; J, White, Fleet-Street;
J.& A. Arch, Gracechurch-Street; and J. Wright, Piccadilly,
M,DCCC.
UJ
ADVERTISEMENT.
THE following tranflation was begun from the Latin Edition
publifhed in Holland, but after the tranflator had proceeded in the
work as far as the conclufion of the fubje6ls defcribed in the two
firft plates, he obtained from Holland the original Dutch Edition.
He has carefully compared the two verfions, and finds that the
Dutch is faithfully rendered in the Latin, and confequently that the
lienfe of the author is not injured by the Englifli being fo far taken
from thence. The learned reader may himfelf form a judgment
of this, by the following paragraphs, taken from the Dutch and
Latin Editions, whereto an Englifli tranflation is fubjoined, and in
which care has been taken to follow the Dutch original as literally
as poffible.
" Wy willen dan hoopen, dat de onderfoekers der natuurlyke
" zaken, die tct nog toe verborgentheden dieper en dieper fullen
" op delven, om alfoo meer en meer de waarheid voor de cogen
" geftelt hebbende, van veele oude dwalingcii, een afkeer te doen
" kr3'gen, waar na alle die de waarheid lief hebben behooren te
" tragten. Want zcy en konnen den Heer en Maaker van het geheel
^ Al, niet meer verheerlyken, ah dat wy in alle zaken, hoe klein die ook
*' in onfe bloote oogen mogen zyn, ah ze maar levejien zvasdom hebben
" ontfangen, zyn Al-xvyjljeit en Vohnaaktheit, met de uiterjle venvon-
dering fien uit Jleken."
Leeuvvenhoeks Brieven, 99fte mifllve.
" Speramiis ergo naturce indagatores omnem in poflerum in id
" impenfuros operam, ut ea, qua? adhuc in ejus fmu occulta latent
" ulterius in propatulo ponant, atque ita in hominibus, veritatis
" lumine illuftratis, antiquorum errorum ingenerent faflidium;
•' quod omnium veritatem amantium fludium efle decet. Kon enim
" hujus nniverfi Dominum atque Opifxeni melius nos glorijicarc pojje
39S0G
" cenfco, qiiam ft fummam ejus Perfe^ionem atque Sapientiam, in om.-
" )iibus rebus, quantumvis ?nido oculo exiguis, modo vitam ac incre'
" mentum nadtis, elucerites., admiremur femper atque celebremus."
Continuatio Leeuwenhoekii Epiftolarum. Ep. 99.
We will hope then, that the enquirers into Nature's works, by
diving deeper aud deeper into her hidden myfteries, will more and
more place the difcoveries of thofe truths before the eyes of all, fo
as to produce an averfion to the errors of former times, which all
thofe who love the truth ought diligently to aim at. For zve cannot
in any better tnamier glorify the Lord and Creator of the Univerfe,
than that, in all things, hoxv fmall foever they appear to our naked eyes,
which yet have received the gift of life and pozver of increafe, zve content'
plate tbe difplay of his Omnijcience and PerfeSiions zvith tie utmofl ad-
miration.
N. U. The Dutch words printed in Italics, arc written under the author's portrait prefixed to
this Work.
The Dutch motto in the title "page, is taken from the works of
Jacob Cats, who has been ftiled by way of eminence, the Horace of
Holland ; the learned reader will find it under the head of " Ge-
dachten; Op 'tgefichte van fchoone Schepfels." As the Tranflator is
not polTefi'ed of any poetical talents, his readers muft be content with
plain Englilh profe.
" When thou beholdefi: the curious works of nature, do not be content with merely gazing
at their beauties, (and canft thou poffibly dwell on them without looking higher?) but
raife thy thoughts to the contemplation of Him by whom every thing that is fair and
beautiful was created."
Cats's Refledlions on viewing the Beauties of the Creation.
The Latin quotation from Virgil, is thus rendered by Mr. Dryden.
" Hence men and beafts the breath of life obtain,
" And birds of air, and monfters of the main."
Dryden's Virgil, /En. B. vi. I. 986.
THE
TRANSLATOR'S PREFACE.
Considering the high eftlmation in which the
Works of Mr. Leeuwenhoek have always been held, it
feems ftrange, that no compleat Engliili Tranllation of
them has. ever appeared. For this, feveral reafons might,
perhaps, be affigned : what feems to me the moft proba-
ble is, that there are interfperfed throughout his writings,
many fubje6i:s of a medical and chirurgical nature, with
Difquifitions of a peculiar kind, which to many Readers
might be offenfive ; fo that I think his works have been
confidered as calculated for the profeffional Man and Phi-
lofopher, rather than for general Perufal, and therefore
have remained in the Dutch and Latin Tongues.
Be that as it may, when I firft read this Author's works,
I found in them fo many wonderful and entertaining dif-
coveries, with fo much ufeful information, that I confi-
dered, whether it was not pradicable to feparate thofe parts
( iv )
from what might be deemed exceptionable ; and, at length, I
determined to attempt the Englifli Sele61;ion now oflfered to
the Public. To make this more correft, I procured, from
Holland, the original Edition in Dutch, by which I have
been able to corre61; fome few miftakes in the Latin Tranf-
lation, though in general it is a very faithful one.
My endeavour has been to ftudy perfpicuity, and ufe
plainnefs of di^lion, fo as to make the book intelligible to
readers of every defcription ; I have given the Author*s
own words as nearly as a Tranflation would admit ; and I
flatter myfelf that I have not omitted any thing material,
which ought to have been inferted in this Selection.
The works of Mr. Leeuwenhock are publifhed in Let-
ters, written by him from time to time, to men of emi-
nence and learned Bodies, and in particular to the Royal
Society of London. The fubjefts are not placed in any-
regular order, and fome of them are treated on at very
different periods of time. In this Sele6lion, I have re-
duced them to fome method, by colle6ling under different
heads, what I found difperfed throughout thofe Letters.
In the original Dutch Edition, the Letters are num-
bered progreffively, beginning at No. 28, and the reafon
why no Epiftles appear prior to that Number, is prefixed
in thefe words :
( V )
'' The preceding 27 Letters, written by the Author,
*' he cannot yet determine to make public in print ;
'* therefore the 28th Letter is the firft that is here pub-
'^ lifhed."
If I may be allowed to form a conje6lure on this occa-
fion, it is, that Mr. Leeuwenhoek had not, by fubfe-
quent obfervation, convinced himfelf of the accuracy of
his firft difcoveries, and, on perufing fome of his firft
Letters to the Royal Society. I faw reafon to be con-
firmed in that idea.
I will conclude with the following teftimony in favour of
our Author, by Sir Martin Folkes, formerly Prefident of
the Royal Society.
'' We have feen fo many, and thofe of his moft fur-
^' prifing difcoveries, fo perfe6lly confirmed by great num-
'^ bers of the moft curious and judicious Obfervers, that
*' there can furely be no reafon to diftruft his accuracy in
*' thofe others which have not yet been fo frequently or
'' carefully examined."
Philofophical TrarifaBions , No. 380, SeB. vi.
INTRODUCTION.
1 O thofe who are acquainted with tlie works of Mr. Leemven-
hoek, or who have been much converfant in INIicrofcopical ftudies,
this hitrodu61:ion may appear unneceflary : but thofe to whom the
fubjecl is new, ^^■iH find fo many wonders laid open to their view,
as perhaps to induce a doubt of the Author's accuracy in his obfer-
vations, or his veracity in his narrations. Indeed, the extreme mi-
nutenefs of many of the fubje6ts on wliich he treats, is in fome
inflances beyond the reach of our capacities to comprehend,* althougli
we may be fully adured of their exiftence. In fadi, it appears by
Mr. Leeuwenhoek's writings, that the difficulty now ftated, was
* The Spcdtator, in one of his papers on the Pleafures of the Imagination, has a paffage
full to the prcfent purpc fe, which is as follows :
' Nothing is more plsafant to the fancy, than to enlarge itfelf by degree?, in its contem-
' plation of the various proportions which its feveral objefts bear to each other, when it com-
' pares the boJy of man to the bulk of the whole earth, the earth to the circle it defcribes round
' the fun, that circle to the fphcre of the fixed flats, the fphere of the fixed ft ars to the circuit
' of the whole creation, the whole creation itfelf to the infinite fpace that is every where dif-
' fufcd about it: or when the imagination works downward, and confiders the bulk of a human
•■ body, in rcfpect of an animal a hundred times Icfs than a mite, the particular limbs of fuch
' an animal, the different fprings which a^^uate the limb?, the fpirits which fet thcfe fprings a
' going, and the proportionable minutencfs of thtfc ftvcral parts, before they have arrived at
' their full growth and perfetStion. But if, after all this, we take the leaft particle of thefc
' animal fpirits, and confider its capacity of being wrought into a world, that fliall contain
' within thofe narrow dimenfions a heaven and earth, ftars and planets, and every different
' fpecics of living crcatur:?, in the fnme analogy and proportion they bear to each other in our
a
( iv )
made a matter of objection by feveral of his cotemporaries, thci-c-
i'ore the foUoAving pallage in his own words, will ierve to Ihite the
objection, and the manner in which it was anfwered by the Author
himfelf.
' I have often heard, tlu.t many perfons difpute the truth of
' what I advance in my writings, laying that my narrations con-
' cerning animalcules, or minute living creatures, are merely of my
' ov/n invention. And, it feems, fome perfons in France have even
' veiitured to allert, that thole are not in trutli living creatures,
' which I deicribe as dilcovcrable to our fight, and alledge, that after
' v.ater has been boiled, thele particles in it which I pronounce to be
* animalcules will be flill obferved to move. The contrary of this,
' however, I have demonft rated to many eminent men, and I will be
' bold to fay, that thole gentlemen who hold this language, have
* own univcrfe; fuch a fpecul.itioii, by reafon of its nicety, .nppcais ridiculous to thofe who
' have not turned their thoughts that way, though at the fame time it is founded on no Ids
' than the evidence of ademonllration. Nay, we may yet carry it farther, and difcover in the
' fmallert particle of this httle world, a new incxhaufted fund of matter, capable of being
' fpun cut into another univerfe.
' I have dwelt the longer on this fubj.fl, becaufe I think it may (hew us the proper limit?,
' as well as the defciftivencfs of our imagination; how it is confined to a veryfmall quantity
' of fpace, and immediately flopt in its operations, when it endeavours to take in any thing
' that is very great, or very little. Let a man try to conceive the different bulk of an animal,
' which is twenty, from another which is a hundred times lefs than a mite, or to compare in
* his thoughts, a length of a thoufand diameters of the earth, with that of a million, and he
* will quickly find that he has no different meafures in his mind, adjufted to fuch cxtraordi-
' nary degrees of grandeur or minutenefs. The underflandhig, indeed, opens an infinite fpace on
* every fide of us ; but the imagination, after a few faint efforts, is immediately at a fland, and
* finds herfelf fwallovvcd up in the immenfity of the void that furrounds it : our reafon can pur-
* fue a particle of matter through an infinite variety of divifions; but the fancy foon lofes
' fight of it, and feels in itfelf a kind of chafm, that wants to be filled with matter of more fcn-
* fible bulk. We can neither widen, nor contract the faculty to the dinienfioiis of either
* extreme. The objetft is too big for our capacity, when wc would comprehend thecircum-
' ference of a world: and dwindles nito nothing, when vvc endeavour af;er the idea of v.n
' aiom.'
., * Spectator, No. 420.'
( V )
« not attained to a degree of proficiency to obferve fuch objeifts triuv.
' For my own part, I will not fcruple to ailert, that I can clearly
' place before my eye the fmallelt fpecies of thofe animalcules con-
' cerning which I now write, and can as plainly fee them endued
' with life, as with the naked eye we behold fmall flies, or gnats
' fporting in the open air, though thefe animalcules are more than a
' inillion of degrees lets than a large grain of fand. For I not only
' behold their motions in all diredlions, but I alfo iee them turn
' about, remain ftill, and Ibmetimes expire ; and the lai-ger kinds of
' them I as plainly perceive running along, as we do mice with the
' naked eye. Nay, 1 fee fome of them open their mouths, and move
' the organs or parts within them ; and I have difcovered hairs at
' the mouths of fome of thefe fpecies, though they were fome thou-
* fand degrees lefs than a grain of fand.
' But fuicc it is pronounced to be incredible, that within the fpace
* occupied by a grain of fand fo many animalcules can be contained,
' and that it is impoflible for me to calculate truly fuch numbers, I
' liavc thought on the following method of computation, to place.
' this matter in a clearer liglit. I lay it down as a pofition or truth,
' that with the microfcope I can fee the fpace occupied by a grain of
'fand* magnified to the fize reprefented by the circle A BGC.
' Next, I Ilippofe that I obferve within this fpace an animalcule
* fwimming or running along, and appearing of the fize reprefented
' at D. Taking the meafure of this by my eye, I conceive the axis
' or thicknefs of the animalcule thus piclured at D, to be the twelfth
' part of the axis of the grain of fand reprefented by ABGC ; there-
' fore, by the common rules of arithmetic, the folid contents of a
* fphere or globe whofe circumference is defcribcd by the circle
'ABGC, will be 1728 times larger than a fphere of the fize of D.
* ' A grain of (;inJ ihe Author i;i anathiT place acfcribes to be of that fj.-t calLJ fcowering,
* fanJj or glafs-grinJers fand.
ujl library'*
vf
( vi )
'Next, I obforve another kind of aiiimalcule, wliicli, mcaiiiring, by
* my eye through a good niicrofcope, I judge the axis or thicknels
* of it to be one fiftli, but fuppofe it only a fourtli jiart of the fize of
' thefirft animalcule D, fuch as is reprefented by the circle E, and
* th.en, by the fame rule, the fize of D muft be 64, times larger than
* that of E; and if this laft number be multiplied by the former,
* (1728) ^ve Ihall find that 110,592 animalcules of tlie fize of E,
' (fiippofing tlicir bodies to be of a fpherical figure), Avill be required
' to make up the fize of the fphere A BGC. Laftly, I perceive a
' third kind of animalcule, the fize of which appears to be only a
' tenth part of the animalcule at E, fuch as the point at F denotes ;
' and that confequently, one thoufand of thefe will be more than equal
' to the fize of that at E. And, if this number be again multiplied by
* the former, it will be plain to demonftration, that more than an
* hundred millions of animalcules can be contained within tlic com-
* pafs of a grain of fand#.'
Tiiis pall'agc refpefts the fize of animalcules, which the Author
reprefents by comparifon with the known fize of a grain of i'and ;
other minute objedls which he frequently defcribes, are, the vcfiels
in the bodies of infe<51:s, the threads of Spiders, the filaments or
threads of wool, the fibres compofing the flefii of animals and the
like. All thefe he confiders as of a cylindrical form, that is to fay,
* ' The folid contents of fpheres bL-ing in the fame proportion as the cubes of their axes,
' the mathematical demonftration of the Author's jiofition is fct down by liim thus: —
12 4 10 1728
12 4 10 64
44
16
100
6912
12
4
10
10368
28
6f
1000
110,592
—
1000
1 10,592,000
( vii )
if hollow, like a round pipe, and, if folid, like a round (lick, wire,
or rope, and he conveys to iiis readers an idea of tiieir niinutenefs, by
comparing them with the known fize of a finglc hair. The method
u'ed by him in afcertaining this proportion he defcribes as follows :
' In examining the inteltines of flies and other infc6ls by the mi-
* crofcope, I have difcovered vefTels conveying the blood and juices,
' the fmalleft ramifications or branches whereof appeared to me more
' than two hundred thoufand times lei's than an hair of my beard.
' And I will liere explain how I compute this proportion, which to
* many may appear wonderful.
' I have a plate of copper, with many lines engraven on it, and
' divided into a number of fmall equal parts. I then carefully ob-
* ferve how many of thefe parts one hair taken from my beard, and
' feen through the microfcope, appears to cover. Suppofmg that the
* diameter of this hair, when magnified, appears equal to fifty of
* thofe parts, then with the point of a needle I trace on tlie copper
' a line, of the fame fize by the naked eye as is equal to one of thole
' fmall veins or vefiels in a fly, feen through the microfcope ; and I
' find that nine of thofe fmall lines fo traced witli a needle, when
' placed clofe together, are a fiftieth part of the diameter of the hair.
' If then 450 diameters of thofe fmall veins which I moft plainly fee in
' a fly are no more than equal to the diameter of one hair taken from
' my beard, it follows,* by the rules of arithmetic, that one of fuch
* Mr. Lceuvvcnhoek here confiders the hair to be round, as well as the fmall veflels he
alludes to, and, fuppofing^each of thefe to be cut through or acrofs the middle, the fe£lion
would exhibit a circle. Now the areas of circles being in proportion to the fquares of their
diaiiKtcrs, the Author's propofition is mathematically dsmonftrated thus:
450
450
2 2i;oo
1800
202,500
( viii )
' hairs is more than 200,000 times hirger than thofc very fmall blood
' vellels in a flv/
The author fometimes computes tlie fize of fmall objccls by ali-
quot or equal parts of an inch, and, for the more readily placing
thefe before the reader's view, the tranflator has fubjoined a fcale of
inches divided into feveral different numbers of equal parts, and in
each of thefe divifions is marked the proportionate fize of the fame
number of i>arts in a fquare inch.
Further, at H I K L, is given a reprefentation of a cube, and at
M N O P, a drawing of a cylinder, in order to convey an idea of
thofe figures to fuch readers as have not been much converfant in
the doctrine of lolids. The number of parts or circles contained in
the cylinder, will not be found to anfwer fo exa6tly to tiie aritli-
inetical computation as thofe in the cube, and this is occafioned by
the interllices or fpaces between the circles in the cylinder, whicli
only touch each other in a point.
■^
5 S « 12
10 15
45 k
niiniiiiiiiiMRiiintiiiiiiiiiiiiiiiiiiiiiiininiiiiiiiiiiiinimiii'iiiii
5 10 15 20 iS 10 L5 20 tS\ 5 10 15 20 2J 30
25 50
55 I
15 30 4f 6o
, j Sctitf ii/'///f//iS iliiiilcil HI/,' ililllriiil /iiii/il; rs ,'r'ri/i',//i<'/ er /(/Uiit /nirls
Of the oak.
The Nature of its Produdtion ; tbe differe^it Degrees of Goodnefs hi
Oak Timber; and tie Caufes of that Difference. The Autlor's
Opinion as to tie proper Seafon for felling Timber.
J.N order to form a true judgment of the nature of this Tree, and
the better to comprehend the following defcriptions of the * veflels,
which compofe the lame, let us firil attend to Plate I- ^g. i -}-,
BCD, and imagine it to reprefent the furface of an Oak when
cut tranfverfely or acrofs the middle, on which furface eighteen
circles appear ; which circles are the clear and undoubted marks of
eighteen years growth, the tree being increafed every year by the
addition of one circle, (and in the latter of thofc years the circles are
the largeft, though not all of equal magnitude, but in proportion
to the fertility of each year.) The fmall portion of this wood,
defcribed in the next figure is marked in the fixteenth circle by the
letter E. Farther, fuppofmg the tree to be fawn acrofs, as above-
mentioned, and afterwards planed or polifiied, we fliall obferve
throughout the furface, fireaks or creafes, reaching from the centre
A, to the circumference B, and thefe are veilels conveying the nu-
* Cy the word veflch, are to be undciflood, throughout this Work, fmall tubes, or pipes,
■running in different diredlions, in tlie fubjedts treated of.
f This figure, which in the original, is only fo many circles, the Tranflator has caufed to
be engraved from a piece of Oak of the fize here dcfci ibcd ; at F is reprefcnted a knot which
was in the tret.
( 2 )
tritlve juices of the plant outwnrds towards the bark, as in the next
figure will be more fully explained.
Fig. 1, AB C D, reprefents a finall piece of Oak, drawn as nearly
as could be done, according to its appearance ^ean tiirough a micro-
fcope, prepared by ine for that purpofe, and which piece of wood
appears to the naked eye of the fize reprefented at//g-. 2, X.
The dark fhades at F F, F F, indicates the part where, towards
Autumn, the vegetation and increafe for that year ceafe; and about
this time, and in this part, the wood becomes exceeding hard, being
compofed of fuch fmall venbls, that it is difficult, and at laft im-
pofhble to diftinguifli them, for which reafon they alT'ume the ap-
pearance of dark flreaks or fliades. Between the letters F F, FF,
is contained that fpace, or thicknefs, which the tree acquires
through its circumference, in the fpace of one year.
This fpecies of timber tree, has five different kinds of veflels,.
three rifing perpendicularly, and two extending, or fp reading hori-
zontally.
EEE, reprefent the firft fort of thefe perpendicular vefiels,.
which are very large, and are produced in the fpring, with the firft
rife of the fap. The infides of thefe vefiels are full of a kind of
veficles, or little bladders, compofed of very thin membranes, or
Ikins, and thefe are to be feen in fig. 3, where, at the letters
L K I M, is reprefented a fe(5lion of one of thefe large veflels, di-
vided longitudinally, and feen through the microfcope.
The fecond fort of thefe perpendicular vefleis is much finailer,
and is alfo compofed of exceeding fine membranes, intermixed v.itli
a kind of Ipots, ^^ hich by the microfcope, appeared to my eye like
globules, or little balls, as reprefented in fig. 4, O N, which exhi-
bits one of thefe lecond fized vellels, divided longitudinally.
The third kind of thefe perpendicular vefiels is exceeding fmall,
but in great numbers : likewife compofed of cxccflively minute
( 3 )
inembranes, and thefe are alfo reprefented wlien cut longitudinally,
or lengthways, ^tfg. 4, P Q.
All thefe perpendicular vefTels, which are found in fo linall a
piece of wood as that before reprefented, and which in fize, is about
the ninetieth part of a fquare inch, do amount in number, in my
opinion, to twenty thoufand ; fo that an Oak tree of four feet in cir-
cumference * contains, according to my computation, more than
three thoufand two luindred millions of thefe perpendicular veffels,
and in a tree of no more than one foot in circumference, will be
found two hundred millions of fuch veflels.
Thefe perpendicular vefiels do, for the moft part, infufe, or inftil
their juices into other vefl'els, which are almoft innumerable, lying in
an horizontal pofition in the tree, and by the means of which it's bulk
or thicknefs is daily increafed : thefe vefTels are of two forts.
F/g. 2, G G G, reprefents one fort of thefe horizontal vedels,
which originally, or at the firft formation of the plant, are derived
from the marrow, or pitii, in the centre of it , but afterwards, in
great numbers, take tiieir origin from the perpendicular veiTels.
Thefe vedels apjieared to my eye like dark flreaks ; but in order to
examine them more clearly, I cut a piece of the wood lengthwife,
fo that they were cut exa6tly acrofs, and then each of them ap-
peared to be formed of five, fix, or even feven veflels joined one
on anotlier, as they are reprefented \njig. 4, intermixed among the
perpendicular veiTels.
The other fort of horizontal vefTels, lyijig in great numbers
or clufters, clofely joined to each other, though not evenly dif-
fufed throughout the wood, when examined in their horizontal
pofition, appear as \nfg. 2, AB, or C D, (but when cut tranfverfely,
* The circumference of a circle being about three times it's diameter, a tree of four feet
in circumference, will be fixteen inches indianut;*r, and one of a foot in circumference, four
•inches diameter, th; fize reprefented in^^. i.
( 4 )
they are reprefented as feen by the naked eye, in Jig. s, RS,) and
■where they are reprefented magnified and feen longitudinally in
Jig. 3, I have in many places drawn crofs lines, to reprefent what I
conceive to be minute valves, and though I could not fee them fodif-
tindrly, as here they are drawn, yet I cannot doubt of their exiftencc,
having frequently feen thefe valves in other woods, and particularly,
very dlftinftly in the Elm ; befides, it feems evident to me, that
without fuch valves the tree could not be increafed in its bulk, on
account of the great force required to feparate and loofen tlie bark
from the tree, in the time of fpring, and alfo for the violent burft-
ing open of the bark, to allow for the growth and increafe of the
wood: and if there were not fuch valves, the juices, which by the
a6lion of the fun are drawn outwards, would, at iun fet, when that
motion of the juices ceafes, be drawn back again, and their exer-
tions to diflend the bark become fruitlefs. A portion of thefe veflels
is reprefented in /;g. 4,, TV, which figure is drawn from a microfcope
of greater magnifying power than that from which the perpendicu-
lar veflels are drawn, in order that thefe horizontal ones may be
more clearly feen: and in this fmall piece of wood, and in this little
fpace, which is no more than the feven hundredth part of a fquare
inch, are more than two thoufand veflels.
It is well known that there is a great difference in Oak Timber,
namely, whether it grew in mountainous Situations, or low lands, and
whether in warmer or colder climates, and laftly, whether it was of
quicker or flower growth. As to the fpecimen of Oak which has
been juft defcribed, it was taken from a tree of thebeil quality, very
compact and clofe grained, and which had been very flourifhing in
its growth.
Oak timber of this fuperior quality we mufl: not expeft to find in
the Northern or cold countries, but in the warmer ones. The very
befl: timber that we have here, in Holland, is brought down thco
■ ( 5 )
Hhiiie from the places of its growth, which are nearly in tlie fame
parallel of Northern latitude with oiirfelves. The Oak which we
have from Riga, Koningfberg, and Dantzick, is very periOiable, and
of a fpongy nature, becaufe it grows in a colder climate, and increafes
in it's bulk much more flowly than that before-mentioned ; but yet
this wood, though fo perifliable, is deemed the beft for making beer-
barrels, becaufe it does not impart any ill tafte to the beer, the rea-
fon of which I take to be, that in cold climates the Oak does not ac-
quire fo much acrid fait as it does in warmer ones ; but I do be-
lieve, that if the better fpecies of Oak, after being cleft into ftaves,
were to be foaked in water for a certain time, this acrid fait would
beextra6led from it, and that the cafks made of it would be greatly
fuperior to thole m.ade of Riga Timber.
The Oak, as has been before obferved, in the beginning of its
growth every fpring, produces very large veflels, but the reft of the
year much fmaller ones ; confequently, wlien the tree fo flouriflies
as to acquire an increafe in it's femi-diameter, or on one fide of it's
outward furface, of one half, one third, or a quarter of an inch,
there will be in this fpace only one feries, or row of inch large vef-
fels ; but on the contrary, where the increafe is flow, then, with-
in the fame fpace of one half, one third, or a quarter of an inch, there
will be formed from twenty to ten, or eleven fuch rows of large vef-
fels. This great number of large veflels in fo Ihiall a fpace, not
only renders the wood very porous and brittle, but alfo very perifli-
able, efpecially if it is ufed in works expofed to much moiflure, and
where there is no free current of air : and hence it is, that fliips
built of French or Englifh Oak, are much more durable than thofe
built of timber growing in the more Northern and cold countries.
In order, more clearly, to explain the nature of the bell Oak
timber, let us revert to fig. 2, reprefenting a portion of a tree which,
in one year, had acquired in thicknefs almoft a fixth part of an inch
( G )
in it's fcmi-diamcter, or one third of an inch in the wLolc, and in
this, one row or circle, and no more, of the very large veflcls, be-
fore defcribed, had been formed. Tlien, to difcern the difference
between this timber and that brou£rht from Ri^a and KoninirflierG:,
let US attend to Jig. 6, ABCDEF, wherein is exhibited a fmalJ
piece of fuch timber mit tranfverfely, and drawn from the micro-
fcope.
The piece of wood which, in this figure, is reprefented by ABC,
or D EF, contains about the fifteenth part of an inch in length*, and
this length, or rather this thicknefs, the tree had acquired in two
years growth, fo tiiat A B denotes the thicknefs produced in the tree
in one year, and is about the thirtieth part of an incii in length ; B C
or E D, indicate the increafe of the following year ; ABC and FED
reprefent the larger horizontal vellels, which in 7%". 2, are explainedby
AB or CD ; and the dark lines HHHH, indicate the fmaller hori-
zontal ones, which in/g. 2, are defcribed by G G G : all tlie round
cavities, of which there are three dificrent fizes reprlented in this
figure, and which are found within the compafs of the thirtietii part
of an inch in length, are the three different forts of perpendicular
vellels before defcribed, Hence we fee that in a tree, which is
augmented in fize, in it's femi-diameter, one inch, or in the whole
diameter two inches and no more, in the growth of thirty years,
there will be formed thirty rov»'s, or feries of large veflels ; from
whence it follows, that tiie greatefl part of Oak Timber, of fuch
flow growth, muft be very foft and perifhable : and if on the other
hand we confider, that Oaks growing in a warmer climate may, in
one year, increafe in fize, in their lemi-diameter half an inch, or an
inch in their whole diameter, we may eafily perceive how large a
portion of wood will be forjTied in them, having only one row of the
large veflels in it, and how firm, folid, and durable fuch wood mufi
be.
* This fize is reprefented infg.^j at X.
( 7 )
Let a tree of flourifhing growth be increafed in magnitude, in the
fpace of a year, one fourth part of an inch, in fuch a fpace v/ill be
produced one circle of the large vefl'els ; another tree growing in
a colder climate fhall require eight or ten years growth to increafe in
the fame degree : in this laft tree, within the fourth of an inch fpace
will be formed eight or ten circles of large veflels, the neceiTary
conclufion is, that Oak Timber growing in cold climates mufl be foft
and peri (liable, and it mult be acknowledged that Oak timber grow-
ing in this country of Holland, is fuperior in quality to that produced
in more Northern latitudes : again, that the Oak Timber of Bra-
bant and Flanders, is fuperior to ours, and laftly, that the French
and Eno^lifli Oaks are the mofl excellent of all.
One thing mull however be confidered, which is, that the very
largefl; Oaks are not always I'o valuable as trees of a more moderate
fize, that is to fay, if they were of good growtli, and are free from
decay; for though large trees, in the firfi: thirty, forty, or fifty
3'ears may gi-ow very faft, and produce excellent timber, yet when
they come to the age of an hundred, or an hundred and twenty
years, the circles of wood added every year, become very narrow,
and the thicknefs increafes flowly, fo tliat the large veflels in the
wood approadi near together, and confequently the exterior or out-
ward parts of fuch large timber become very foft, in comparifon
with the inner part of it.
It is the general opinion in this Country that timber is much
more folid or durable when felled in winter than in I'lnnmcr. But
I think that if we exainine this opinion, we fliall find it to be erro-
neous.
It is true, that if timber be felled in the fummer time, the bark
can much more cafily be feparated from it tiian in the winter ; for
tlie wood newly formed each year always adheres to the bark, and
the bark is every year propelled or driven outwards from the lafi-
( 8 )
year's wood, and as the tubes or vefl'els of wliich fucli newly formed
wood is compofed, are during the time of their growth not i'olid, but
of a very foft texture, this is the reafon why the bark can be fo eafily
llripped off in the fummer time. But that any part of the tree, ex-
cept that of die new growth, fliould be more fohd in winter than in
fummer, fecms to be altogether impofllble ; for it is plain to demon-
ftration tliat all trees are compofed of multitudes of fmall tubes or
veflels, which are formed every year by the tree's grov/th, and that
when once formed they preferve their fliape and fize, without any
alteration, although the tree be above an hundred years old. Thefe
tubes, which in all fcafons are filled with juices, are neither lefs in
winter nor larger in fummer, for the juice which circulates through
them is at all times the fame. But if it were polTible that the fub-
ftance of trees in v/inter could be more clofe or compadl, and in
fummer more fpongy or diftended, it would follow that the hard
and dead bark furrounding the tree would in winter be leparated
from the wood, and in i'ummer more fpiit open than it is found to be;
but fince we do not obferve this to happen in either inflance, it muft
be the better opinion, that timber felled in fummer is equally good
with that cut down in v/inter ; and if any one will take the trouble to
examine thole fmall chinks or fifl'ures which are produced in the bark
during the tree's growth in fummer, he will find that trees are not
increafed in their fize or fubftance in an hafly manner, but by very
€ow degrees.
Of the fir.
The different Degrees of Goodnefs in Fir Timber, hozv difcovei'able ;
the minute Vejfels which enter into the CompofUion of this Tree de~
fcribed at large.
In treating of the Oak I liave confidered, tliat the fpecies of it
growing in warm climates, is fuperior to that which is produced in
cold countries. But we muft not imagine this to be the cafe with
all Woods ; on tiie contrary the Fir Timber growing in cold coun-
tries IS fuperior to that produced in warm ones, where its growth
is rapid. For the perpendicular veflels of which the Fir is compofed
are comparatively fmall, and though we may fee here and there
in this wood a large perpendicular veflel, that is no great exception
to the general nature of it.
In the Fir, at the beginning of its growth every year, the per-
pendicular velTels, (which are all of the fame kind), are formed
twice as large as thofe towards the end of the feafon, when the
growth ceafes, and thefe latter- formed veflels are, in refpe6t of their
component woody parts, very compa6l and clofe, having very
fmall cavities, and confequently producing durable timber ; and
the lefs this tree grows every year, the greater number of thefc
compaft vefli^ls enter into its compofition. Hence we may gather,
that if, upon examining Fir Timber at the ends, when it has been
B
lo ;
cut or fawn acrofs, we obferve tlie circles, denoting cacli 3^ear's
growth to approach very near together, we may eafiiy conclude
that fuch timber is firm and durable, efpecially if we -perceive
great part of thefe circles to be moiftened or tinged with a refinous
or gummy fubftance, named Turpentine.
The produ6Vion or growth of the Fir is fhewn in Plate ^-fg- 7.
which reprcfents a fmall piece of this wood, as feen by the micro-
fcope, when cut tranfverfely, in order to fliew the difference be-
tween the perpendicular veilels formed in the Spring, and tliofe pro-
duced in Autumn, when the growth ceafes.
The natural fize of the fpace contained between ABC, or EFG,
is about the fifteenth part of an inch in length ; ABFG, denote that
portion of the wood formed towards the latter end of the year, and
the line of feparation appearing at B F, is the place where the increafe
for that year ceafed. BCEF indicate a part of the fame wood,
produced in the beginning of the following year.
DD, and GG, are the horizontal velT'els, which in tliis wood are
placed very clofe to each other, fo that when cut tranfverfely it is
difficult to diftinguifli them.
In this figure, we fee.the difference between the velTels formed at
the beginniiig and at the end of each year's growth. And if the wood
here reprefented, within the fpace ABC (which is the fifteenth part
of an inch) required two years to enlarge the femidiameter of the
tree to that thicknels, it follows, that in this fpace there will be two
rows or circles of the compact vellels pi6tured, between AB. More-
over, the piece of wood wliich is here defcribed was from a tree of
quick growth, and timber of flower growth not only would produce
fewer of the large veficls, but alfo thofe vefibls firlt formed in the
fpring would be fmaller in proportioii, efpecially if growing in a
colder country, and in a good foil. In a word, the nearer the cir-
cles before mentioned approach togetlier, tlie flower was the
growth, and tins fpecies of Fir is the moft durable.
. ( 1^ )
In refleoling upon the nature of the tubes or veflels of which wood
confilts, I confidered with niyfelf, whether each of thefe tubes was
not formed of two difl;in6t kinds of exceflively fmall veflels or coats,
one fort extending lengthways, and the otlier fort encompaffing
each tube in a circular direction, as I had obferved the quills * of
feathers to be formed, in order to give to each tube a degree of
firength and firmncfs.
To inveftigate this, I examined feveral kinds of wood, and
particularly the Fir, and at length I obferved in fplitting the
larger tubes or veflels of the wood, that fome of them were in-
dented or jagged in the fplitting, and I alfo imagined tliat I faw
the tube to confift of fmaller veflels in a (trait perpendicular direction
which were not difFufed all over the membrane or coat, but only
placed on each fide of it, whence I gathered, that though the minute
veflels, fome of which 1 conceived to extend longitudinally, and
others toencompafs each tube of the wood, cannot always by reafon
of their exceeding fmallnel's be difcovered, yet that the tubes are in
reality formed like the quills of birds in order to give them the greater
ftrength.
In further profecuting this inquiry, I procured a piece of the Pitch
Pine or Fir newly felled, and whicli had been of very quick growth ;
and having placed a fmall part of it before the microfcope, I dire6ted
the Engraver to copy the figure of it as exactly as poflible.
Fig. 8, ABCDEFG, reprefents this fmall piece of wood, which
I fplit longitudinally as thin as poflible. It's extreme thinnefs brought
clearly into view a great number of globules contained in the veflels
of this wood, and which aiford a mofl: pleafing fpediacle, not only
on account of th.eir exaft globular figure, but alfo becaufc in each
of the globules is a lucid or bright fpot.
I1iis fmall piece of wood I found particularly eligible for my
* The Author's examination of this fubje£t will apprar in the courfe of the work.
Ba
( IS )
obfervations, partly becaufe it is very rare to find a piece fplit out
fo long, and fo t!iin with the perpendicular veiTels lb clearly difcern-
ible in it without obllru^tion to the fight from tlie horizontal ones,
and partly becaufe I have feldom found fo many of the globules in
fo fmall a fpace. Thefe globules in my opinion are the fubfiance we
call Turpentine, and from which, by biu'ning the wood, Pitch and
Tar are procured.*
Between DE and F, are to be feen the tubes of the wood when
divided, which plainly appear to be fplit, not exaftly ftrait in length',
but in a manner indented or jagged and broken fidewa3's.
I alfo put into the Engraver's hands two feparate microfcopes that
he might make diftin6l drawings of thefe tubes of the wood, and
from one of thefe was taken /^. 9, M N, where two of fuch tubes
are reprefented when fplit lengthways ; but the Engraver faid that
he could not pofTibl}' draw all the jagged parts which he faw. And
we both of us perceived in the broken membrane or coat of the tube;
many excellively minute veflels, which by reafon of their fmallncfs
he was unable to exprefs in the drawing. Fig. 10, O P, rcprefents
a fingle tube of the wood, in which, as plainly as could be done, is
reprefented the broken parts of the membrane of which the tube is
chiefly compofed.
Since then we find by thefe obfervations, that the very fine mem-
branes of which thefe woody tubes confift, is not always fplit length-
ways, but often in an indented or jagged form, we may eafily cozi-
ceive that the tubes of wood, however minute they be, are partly
formed fimilar to the quills of feathers.
* It is well known, that TLirpcntinc is procured from the Fir, by making a wound or incifion
in the Tree, from whence the Turpentine flows in great alnindance. This, upon being diftillcd
produce^ the fpirit of Turpentine, and what remains at the bottom of the ftill, is the fubliancfr
called Rofin, — Pitch and Tar arc obtained by burning large quantifies of the billets of Fir, either
in the open air, covered with fods to prevent evaporation as was the aiKient practice, or in ovens
conftructed for thatpurpofc, as is ihe modern method.
( 13 )
The filTure or fplitting of the particle of wood, reprcfented in
fig.^, was in fuch a direftion that, as I may fay, it palled or took
its dTe6lion through the center of the tree, by whicli means the
horizontal vellels, as well as the perpendicular ones, were divided
longitudinally, and therefore are both exhibited in the fame Fgure.
Between K I and H G, the horizontal tubes or velTels are repre-
fented when divided longitudinally. Thefeveflels a,re Ibund in great
abundance in this wood, and in fome places fix, feven, or even. twelve
of tliem fliall be found clofe together, and it is very rare to fee fo
large a fpace of tiie perpendicular ved'els without horizontal ones, as
is between G and F in this figure, though the real fizeof that fpace
is not more than the thicknels of a large grain of fand.
I have often refle6led on the nature of thefe horizontal vellels,
that is, how they are formed, and how fupplied with nutritive juices^
for through them a new coat of bark is every year pi'oduced round
the tree. At firft, they undoubtedly have their rife from the mar-
row or pitli in the center, but afterwards they mult necellarily pro-
ceed from the afcending vellels. In this enquiry I could not fully
fatisfy myfelf, except tliat I obferved the appearance of certain
fmall dots or points in many parts of the perpendicular vellels, which
at length I difcovered to be no other than fmall round apertures.
Thefe are reprefented in fg. 8, between B C, and G H, and as I did
not fee them in any other places than where 1 had clivided the hori-
zontal from the afcending vellels, I concluded that at thefe fmall
apertures the horizontal velTels are united to the perpendicular ones.
And I began to ccnfider whetiier the afcending tubes were not air
vellels, as well as inftrumental in conveying the nutritive juices.
I then fat about a more accurate examination of this wood, by
cutting off thin flices with the fharpeft et^ged tools I could procure,
and placed them before the microfcope, and hereupon I difcovered
a much larger number of afcending vcileis than I had before
( 14 )
obferved, whicli la ft difcovcrcd vefiels were exceeding fmall in com-
j)arilbn of the former ; fo faiall, indeed, that if a large grain of fand
were divided into ten millions of parts, thefe veflii'ls would flill be
impervious to them. Hereupon 1 concluded that all the perpendi-
cular veOels which I had before difcovered in this wood, and through
wliich I had fuppofed the juices for the nourifhmet of the tree, and
its fruit, were conveyed, were really only air vellels ; for thofe
v.hich I now name air vedels are furrounded with three or four of
the very fmall vellels before mentioned. And I am clearly of opi-
nion, that thefe minute vefiels do conftitute and form thole others
which I name air vefiels, and conne6l them one with another ; and
that thefe fmaller vefiels convey all the nutritive fubfi;ance for the
fupport of the tree, its leaves and fruit, and that therefore they may
properly be named arterial vefiels.
The wood which in jig. 8, is reprefented f})lit longitudinally, I
now cut or divided tranlVerfely, to fliew the nature of thefe vefiels
when infpe^led into or looked down upon, if I may fo exjn-efs my-
lelf; and sit Jig. ii, UVWYZ, a portion of it is reprefented as feen
by the microfcope, the natural fize of which was no more than
could be covered by a middling fized grain of l\md ; and in this
figure, between the vefiels compofing the wood, or the air vefiels
before mentioned, are feen the very minute vefiels which I call the
arteries of the wood cut tranfverfely ; but as they are fo very mi-
nute, I caufed four of the air vefiels to be drawn I'eparate as viewed
by a ftill deeper magnifier, that thefe laft might be the better dif-
tinguifiied, and thefe are fliewn at fg. ly, as they he between the
air vefiels.
The dark ftreaks which are reprefented mfg. 1 1 , at W Y Z, are
a fmall part of the horizontal vefiels divided longitudinally, and
which vefiels are reprefented in/^.8, between G H, and I K.
To this defcription I muft add a little piece of the fame wood which
( 15 )
I cut longitudinally, buv in a different manner from that defcribed
in fig. 8 ; for as in that figure the wood is reprefented when fo Iplit
that the air velTels, and thoi'e fmaller ones which I call arteries, and
alfo the horizontal tubes of the wood, are all divided longitudinally,
here on the contrary the perpendicular veflels are fp^it or divided
longitudinally, but the horizontal ones are cut obliquely.
Fig. 13, LMNO, reprefents fuch a particle of the wood in which
the horizontal veU'els may be feen placed fo clofe to each other as to
be only feparated by one or other of the air veflels. Thefe horizon-
tal velTels lying fo clofely and regularly befide each other it is no
wonder that this kind of wood is of all, the mod eafily fplit, and
Itrait in the fplitting.
I have caufed a feparate drawing to be made of thefe horizontal
tubes or veflels in their pofitions adjoining to each other, in order
the better to diftinguifli how they lie among the perpendicular ones.
F/^. 14, PO, reprefents thefe horizontal tubes or veflels, many
of which are feen in fig. i^. Thefe veflels in fome places lie twice
as clofe together as they do in others; and upon examining them
with the greateft accuracy I was able, I muft fay that I f;iw two
kinds of thefe horizontal veflels or tubes of the wood, one fort of
which was fo much fmaller than the other as almoft to efcape the
fight.
For the more fully elucidating this fubjeft, and for the informa-
tion of any who may have the curiofity to repeat my obfervations,
I have in fg. 1,5, given a drawing of the manner in which I cut or
fplit the wood. In this figure AB C DF, reprefents the fourth part of
a round piece of the tree or a branch of it, of which B denotes the
center of the tree or branch ; at G is (hewn how the particle of wood,
reprefented in fg. 8, was fplit off; at C, how the particle repre-
fented in figures i - and 12, was cut off, and at E, how the particle
reprefented in fg. J3, was fplit off.
( ^6 )
1 have fometimes (as I before hinted) fecn fome of the perpendi-
cular or aicending veflels in the fir, much larger in diameter than
others ; but thefe are fo few, that it is very rare to obferve them.
Injig. 8, between B and C, are to be feen the minute round
apertures in thofe parts of the afcending tubes or air veflels, where
the horizontal ones are feen, which apertures I conceive are deftined
to tranfmit air or the juices of the tree, from the afcending to the
horizontal veflels.
Thefe difcoveries of mine, refpe6ling the fmallnefs or thinnefs
of the veflels or tubes, coinpofing the fubftance of trees, may not
eafily be credited by many, as not comprehending how, by reafon
of their exceeding Imallnefs, any juice or liquor can poflibly pafs
through them, and, what is more difficult to conceive, how through
i'uch veflels afcending perpendicularly, any nutritive fubftance can
be derived from the root of the tree to the extremities of the upper
branches.
But as, on the one hand, it is out of the reach of our finite capa-
cities to comprehend the extent of the Univerfe ;* fo on the other,
we are equally unable to conceive the minutenefs of the veflels and
component parts of which not only animals, but alfo vegetables are
formed, and much lefs, how the parts of matter are united toge-
ther, or how one part grows out of, or is added to, another.
* This fentiment is more fully exprefled and largely dilated on, in the SpecStator, No. 420,
and many of the reafonings in that Paper feem to have been taken from the difcoveries then
xiewiy made by our Auihor and his cotcmporaries.
Of the weevil or CORN- BEETLE.
Wherein the common opinion that this Infect is bred in Corn Jponiane-
oujly, isjhezvn to be erroneous ; the true nature of its Generalio7i ex-
plained; with tie means to preferve Corn from its infection.
1 HAVE heard it flrongly argued, that the Weevil or Corn-
beetle, (which is a very noxious infe6l, well kriown to corn dealers
and bakers in this country,) is produced by what is called equivocal
or fpontaneous generation, that is to fay, from inanimate fubflances
Avithout any parent. The principal reafons alledged in fupport of
this opinion are, that we often find this infe6l in a new granary,
where never wheat was kept before, and therefore it is deemed a
neceflary conclufion, that W^eevils are not propagated by the
ordinary courfe of generation. Again it is faid, that we may open
many grains of wheat, which are found and uninjured, fo that no
inark of a perforation or hole, fliall be difcernible on the outfide, yet
within thefe grains Oiall be found perfeftly formed and living
Weevils.
The anfwer which I have given to thefe arguments has been, that
thcfe little animals may, by ourfelves, be removed from one grana-
ry to another without our knowledge : for fuppofing the perfon em-
ployed to remove corn, to have come out of a granary, or barn, in-
fefted with Weevils, he may eafily carry fome grains of corn contain-
ing them, or fome of the infe6ls themfelves, flicking about his clothes,
or in his flioes, and thus remove them into a granary where none
C
( i8 )
had ever been. Bcfides, the fliip, M'agjgon, or cart, employed to
carry corn, may be iiifcdted with Weev.ls, by having carried grain
in whicli they abound, and thus from a fcv/ of thefe in!'c61:s, multi-
tudes may be produced by the ordinary courle of generation.
But in order fully to invefligate the truth of this.Idefircd the per-
fons who had argued this matter with me, to bring me the lirft
Weevils tliev themfeives fhould find, (it beinsr then the winter fea-
fon) ; and on the 13th of Marcli, I received forae grains of wheat,
(manv of which had the infides eaten away) mixed witli Weevils.
I took three glafies, in each of which I put fix, eiglit, or nine
Weevils, and eiglit, ten, or twelve grains of wheat, which wheat
I was tlie more aflured could not be infected, becaufG'it had been
kept for feveral months, clofely covered up, in my Ihidy. In a fourtli
glafs I put fome Weevils without any wheat, but this l^ft mode of
experiment I afterwards rejefled, obferving that in. the Ipace of
twelve days they all died. As to the other three glades, the weather
being cold, and, obferving the animals, for tlie mod part, to lie
motionlefs, I put them into a leatiier cafe, which I always carried
about me. And I had no doubt, but I fliould clearly prove to all,
that the Weevil proceeds from a maggot, for which reafon 1 fre-
quently examined tiiefe objeils by the microfcope.
I, atfirft, entertained an opinion, that the Weevil, like, the Silk-
worm's moth, and many other infe61:s, did not, while in that fliape,
take any food : but herein I found myfelf mifraken, and obfervcd
that the Weevil not only feeds upon wheat, but that it can excavate
or fcoop out the whole contents of every grain, and creep about in
the infide, being provided with a beak, or trunk of a great length, in
proportion to the fize of its body, at the extremity of which are cer-
tain exceedingly fmall organs, or inftruments like teeth, and with
thefe it can bore or pierce through the outward hufk or ihell of the
wheat, and thus open to itfelf a paffage to devour the contents.
At a fortnight's end, namely, on the 27th of March, I obfcrved
( ^9 )
fome of thcfe W cavils coupled tcge'iher, and from this time I fre-
quently ini"(ie6lcd ihem, but fuw no appearance of any living creature
hens; produced from them until the loth of June, wlien I obferved
lying- among the Weevils and the wheat, two fliort and thick little
maggots, cne of them about the fize of a large grain of fand, and
the other itbout t-^e fo.irth part larger : feeing this, I opened one of
the q-IafTeii in whirJi I had enclofed fix Weevils, and examined the
ditreierjt grains of wheat that liad been put in with them, and found
two of them to be entirely hollow and eraptv ; from another of the
grains, which by the external appearance was the leaft eaten or con-
fumed, but had many fmail perforations or little holes not difcerni-
ble by the naked eve. I drew out a perfectly formed Weevil, which
was of a 3'ellow colour : v/liereas thofe which were at firft brought to
me, and had been iluit up in the glals for three months, were of a
deep red, almoil aj-.proaching to black.
In another grain of the v,'heat I found a Weevil, of a very pale or
white colour, Vvith its claws, horns, and beak, or trunk, lying clofe
to its body, in exaft order, as we fee the wings and legs of a Silk-
worm's chryfalis or aurelia, when it is almofi; arrived at the ftate of
a flying ip.fecl, only with this difference, that the unformed Weevil
is not inclofed in a Ihell or cafe, like the aurelia of a filk worm.
In other grains of the wheat I found maggots of different fizes, and
from one grain I took out a perfedlly formed Weevil, whofe white
colour ^^^s changing to a red, and \\hich was continually in mo-
tion.
KKamining the other glafles, I found fome of the grains of wheat
iiertorated with little holes, and others half eaten. Some of the
Weevils which had been Unit uj) in thefe glalles I opened, and in one
of the females, I found five white eggs, which I conceived to be of
their full fize: in others I obferved eggs, fome of which were ar-
rived to maturity, and others gradually lefs and Icfs.
Hence I concluded, that whereas the Silk-worm's moth, living
( 20 )
only a few days, in that time lays a multitude of eggs and then
dies: on the contrary, the Weevil, which every day produces but
few eggs, is a long lived animal, and by this means may be as pro^
lific as Silk-worms or other infects : for the Weevils which 1 am
now treating of were all alive the preceeding fummer.
As to the two maggots which I at firll found in the glafs among
the wheat, I had no doubt .hat they had fallen out of the giains
wherein they had been firfl depofited, by reafon that thofe grains
had been rather too much eaten away before the eggs were laid iiv-
them, and the holes which had been made in them rather too large ;
and, as all creatures, however minute, are endowed with moft ad-
mirable faculties and powers to ani'wer the ends of their creation, I
think it very probable that the large trunk or beak with which this
infe6l is provided, (furniflied with teeth or pincers,, which open and.
Ihut in exa6t correlpondence with each other,) is given to it of fuch-
a length that it may be enabled to bore a fmall deep hole in every
grain of wheat, and therein dcpofit an egg, otherwife the maggots
breeding from, thefe eggs would never grow to maturity : for if a
W^eevil were to lay its egg on the outfide of a grain, and a maggot
Ihould be hatched from it, fuch a maggot could not pofllbly pierce the
hulk of the wheat. Again, were a Weevil to lay more than one
egg in one grain, and all thefe eggs produced maggots, they would
hinder each other's growth, for want of having iufficient nourifh-
inent, inafmuch as one grain is not more than fufficient to nourifli
one maggot, and fo to produce one Weevil.
I obferved in opening one grain in which a fmall hole had been
made, and out of which I took one fmgle egg, that round about that
part where the egg was placed, the mealy fubftance of the wheat
had been loofened or reduced to powder, from whence I concluded
that the parent Weevil, before it laid the egg, had by means of its
trunk, ieparated the particles of meal in that part, both to make a
( 21 )
foft place for the egg to lie in ; and alio, tliat when the minute
maggot fhould creep out, it might find this foft and loofened meal
prepared for ite firfl: feeding on^
Some of thefe maggots I placed in glades by tliemfelves, and ob-
ferved them gradually to aflume the form of Weevils, the beak,
horns, and claws, appearing by degrees, and the colour alfo chang-
ing from a white to a yellow, and then to the red colour of the
Weevil;
As I had obferved, that none of thefe infecls which w^ere kept in
glades together v.ith graiiis of wlieat, ever depofited their eggs on the
glafs, I put three females into a glafs by themfelves, and in the
fpace of twenty-four hours they laid four eggs. One of which eggs
drawn from the microfcope, is repreiented in Plate 11.^^. i, ABC.
In the fpace of feven days thefe eggs produced the kind of maggots
before mentioned, which, when firft hatched, Mere not larger than a
grain of fand, and one of thefe as lying on its back, and drawn from
the microfcope is reprefented at j^g-. 2, wherein D E F, is the head
and FGD the body. This maggot was in continual motion, but
when a little at reft, it contra(5ted its body together, and in this po-
fition the limner drew its figure, and when it attained to its full fize,
the Ihape remained the fame until the time approached for its being
changed into a Weevil. Another m.aggot whicli I had fixed orfaftened
by its hind part before the microfcope, I caufed to be drawn when it
extended its body, and this is diewn ^t fig. 3, H I K.
Thele maggots have very little ftrength to move from place to
place, fo that it feems defigned by nature, that they fliould be fed
no where but in grains of corn : for if a Weevil were to depofit its
egg in any place, except in the infideof a grain, it would in my opi-
nion, be impodible for the maggot thence produced to procure any
nourirhment and become a perfect Weevil.
Tueie things confidered, we may be fully fatisfied refpe(51;ing tlie
( 22 )
*
reafon, wliy in corn, wliich is frequently moved and Ihifted, the
Weevil can increafe but little : for fuppofing one of thel'e infects to
have pierced and prepared two or three grains ready to depofit its
eo-gs, and foon afterwards the com is moved or fpread about, tlie
animal, when it is ready to lay an egg, finding no grain prepared to
receive it, mud leave fuch egg on the outfide of the corn, where the
young maggot, when hatched, will be in the fame fituation as feed
fown in barren land, and confequently muftperilh. But if fuch corn
is undifturbed, tiie Weevil may multiply, in a great degree, by de-
pofitlng its eggs in the grains fitly prepared for them, and which may
be confidered as fo many nefis for the reception of the young. Again,
the long life of this infe6l caufes it to multiply exceedingly, for tlie
Weevils which I received iit the month of March, (the youngcfl of
which was undoubtedly a year old,) were alive and vigorous in Jurre
following; and who can tell how long the natural life of this infefl
may be ?
For the information of thofe who never faw a Weevil, one of thefe
infects is reprefented of its natural fize ^t fig. 4, X, and underneath
it, I have given a drawing of its beak or trunk, as feen by the micro-
fcope, to fliew by what organs or inftruments this creature is enabled
to pierce the corn, partly to feed on the contents, and partly to de-
pofit its eggs in the fmall holes it makes therein : for, as otl^er ani-
mals are taught by nature to prepare their nefts for the reception and
fupportof their young, fo it is the peculiar inftin^l: of the Weevil to
aim at depofiting its eggs in no other place than where the little ani-
mals produced from thofe eggs fiiall be able to find fubfiftence, and
this is in the grains of corn.
At MNOP is represented the probofcis, trunk, or beak of the
Weevil, which naturally is not fo ftraight as liere pi61ured, but ap-
pears bent downwards when feen fideways, as marked at M O O ;
but had the figure been drawn in that view, the opening at the ex-
( "-3 )
tr-emity with its pincers or teeth would not have been vifible, as it is
now to be fe^n at O : within this mouth or orihce are two fdngs or
piercers which are continually in motion and one of which is I'een in
tlie figure, but 1 never obi'erved the animal to protrude or thruft
tliofe Itings or piercers farther than the extremity of the pincers at
O ; fo that I imagine the only ufe of thefe organs is to break or di-
vide the hulks of the wheat and the meal within it ; and, having fre-
quently contemplated this animal, while feeding, 1 obferved it, after
having thruil its trunk, into a grain of wheat,, to (tick fo clofely to it,^
that, though tofied about, it would not let go its hold. .
y r, are the two horns ; LMR, is part of the head ; and at M
are reprel'ented* a coliectJon of globules, which through the micro-
fcope exhibit the fame appearance as if by the naked eye we were to
lee a parcel of very minute black coral beads placed iir exacl order
clofe together ; and this 1 concluded to be one of the eyes.
I am not very fond of drawing the whole bodies of fmall animals
from the microfcope, becaufe I con"der that to be of little utility ;
and this is the reafon why I have only given a figure of part of this
infe6l when marrnified.
I trull that thefe experiments and obfervations will prove that'
Weevils cannot be produced, otherwife than by propagation, that
is to fay, by copulating and laying eggs, from which eggs maggots
proceed ; and finally thofe maggots are changed into Weevils. But
whether the vulgar will be hereby convinced of the error of their
opinion in this refpeft, I much doubt,^ being continually peftered with
their obje^lions to what I have advanced. It is, however, with me,
a mail certain truth, that what I have demonftrated refpedfing the
* To thofs who have not been much converfant in thefe objects, it may feem ftrange that
acolleftlon of globules or little balls fhould conftitute but one eye; but fuch readers will be
pk-af:d to underftand, that in moft infedls, each eye is formed of a great number of fmaller
optical organs, or eyes, and this fubjeft will be found amply dil'cufled in the courfe of this
work.
( n )
Weevil, name!}', that it cannot be produced otlicrwlfe than bs
generation, does alfo hold good with regard to all creatures endued
with life and motion. And although this is a very- minute animal, yet
its fpccies muft have been continued in the way 1 have laid down,
from its lirll being formed at the creation : and were it otherwifc,
namely, that from inanimate matter, fuch as flones, wood, earth,
plants, or feeds, this or any other animal fliould be produced, that
•would be a departure from the general courfe of nature ; and fuch
formation or new creation, mufl be continually derived from the fu-
preme Almighty Creator.
Probably what I here advance may appear ftrange to fome, and
they may perhaps wHh me to enquire into the propagation of other
minute animals.; but for the prefent I leave the profecution of thefe
matters to thofe who may chufe to beflow as much labour thereon
as I have done in this examination of the Weevil, affuring them that
my obfervations are tiie refult of more than four months application
to the fubjedl.
4-
Of the Maggot or Caterpillar injefling Corn in Granaries; the nature
of its generation explained, and tine means to prevent its increafe
pointed out.
AVING, as I hope, by my obfervations on the Weevil, convinced
mankind, that it is propagated in the ordinary way of generation, I
have fince employed myfelf in the examination of that hife6t or mag-
got which our bakers and corn dealers name " de JVolf."*
This creature is a very fmall white maggot, provided with two
red pincers, or organs like teeth, placed in the fore part of its head,
by which it not only feeds on, and confumes wheat, and other grain,
but alfo can perforate or gnaw holes in wood. The common opinion
is, that it is produced from corruption, or elfe from what fome call
a blight. But, in order to refute this vulgar error, I procured from
a Merchant, a box of wheat, in v/hich this infeil abounded, that I
might difcover to all, the real manner of its propagation.
Upon infpe6ling this wheat, I found, that one fmgle maggot had
ftuck or faftened together from five, to fix, feven, or even eight,
grains of wheat, in one of which itfelf was concealed, and that moft
of the other grains were hollowed or fcooped out in the middle ;
and it feems to me that tiiis maggot is much more pernicious than
* Tli.^t is, in Englifli, "the Wolf." This Infc(5t is not much known in England
among*the country people, for the Tranllator having procured from an Importer of Corn,
■a fample of Piuffian wheat infeftcd with it, and fliewn it to feveral farmers, tlie appearance
feemed new to them, nor could they afiign to the animal any name in Englifh. But to the
Dutch, who have always been great importers and exporters of corn, it feems to have been
familiar, and the Author's rem.irks on this fubjccl may be well worthy the attention of our
Englifli merchants.
D
( 26 )
tlie Weevil, bccaufe it fcattcrs a great quantity of its excrements in
the fliape of white round balls, which are very large in proportion to
the fize of its body.
. Moreover, this maggot has in the anterior, or fore part of its
liead, an organ, or inftrument, through which it continually fpins
an exceeding fine thread, which thread it fixes to every fubftance it
approaches. By this means its body is always fupported lo that it
cannot fall, and in a clean glafs it can move from place to place,
being fufpended by this thread, and by this thread alfo it connects
or binds the grains of wheat together.
Some of this wheat I put into a glafs tube, about the fize of a
finger, and a foot in length, clofing each end with a good flopper,
and the reft of the wheat I kept in a wooden box. But, towards the
end of the fummer, I obferved feveral of the maggots forfaking tlie
wheat, and fattening themfelves to the glafs, and others of them I
faw creeping about among my papers, and I found the box, in which
I had put them, perforated in two places, through which many of
them had efcaped. I alfo faw the ftopper to the glafs tube gnawed
into, as deep as the thicknefs of a linger, and upon taking it out, I
found that eight or ten of the maggots had crept into it ; upon which
I placed them again in the glafs tube, with the grains of wheat, and
flopping the orifices with a cork, I covered the cork on the outfide
with fealing-wax, to prevent the maggots again efcaping, but at the
fame time I contrived a fmall aperture that they might not be de-
prived of air. Plate II. fig. 5, ABC D reprei'ents this glals tube, of
which AD, andBC are the two extremities, each doled with a
Itopper covered with fealing-wax ; EG and F H are two fmall glafs
tubes, paffed through the ftoppers, to fupply the maggots with frefh
air, but thofe apertures were fo fm.all as not to permit their efcape.
About the fame time that I was employed in thefe obfervations, I
vifited a granary infefled with this infedl, and faw th? maggots, in
great numbers, creeping up the walls, from whence I concluded.
( 27 )
that in like manner as the maggots in the glafs tube quitted the wheat,
and lodged themfelves in the ftoppers, i'o in the granary they con-
cealed themfelves in the linings and beams, until their transforma-
tion into flying inledls fliould be compleated. And I was confirmed
in this opinion by obferving the granary to have been fo perforated,
or eaten into by thefe maggots, that not a fingers breadth was left
untouched by them.
I alfo obferved tliat great part of the Hopper which was within
the glafs tube, was gnawed or reduced to powder, and many cliinks
or crannies formed in it, and though the maggots endeavoured to
conceal themfelves within the ftopper, yet three of them remained
in the glafs, in which they lay quiet the whole winter, and they
were fo little covered with their web or thread, that, with the micro-
fcope, I could difcover them move their heads.
On tlie 29th of April following, I faw them begin to alTinne a red-
difli colour, and to be fomewhat contracted in length ; the next day
the rednefs increafed, and they feemed to me to be turned into
aurelias.
At the fame time, upon examining the w'heat, which was kept in
the box, and had been full of the maggots, I found that they had all
efcaped through the holes perforated by them in the box.
On the 23d of May, the aurelias before mentioned, had become of
a red colour, and the next day I faw a flying infe61, which is called a
Moth, fluttering about the glafs tube. This had proceeded from one
of the aurelias, which liad been the chief fubje6l of my obfervations,
and I law lying near it, a pellicle, or little fkin, which had been the
cafe or fheath in its aurelia ftate.
Two days before difcovering this moth, I had obferved feveral of
the fame winged infefts flying about my fiudy, two of which I killed,
and upon examining them by the microfoope, I found them to be
formed in the fame manner with this in the glafs, fo that I was con-
vinced they had proceed from fome of the maggots which had efcaped
( 28 )
out of tlic box. And on the 25th of May I faw two more moths-
tome out of the llopper to tiie tube, leavizig their fhells or cafes
hanging to it.
As many perfons are unacquainted with the figure of thefe moths,
I have caufed a drawing to be made of them, which is to be feen at
fig. 6, A A ; and alfo a drawing of the covering, lliell or cafe which
enclofes them while in their aureha (late,^^. 7, PO. Thcl'e figures
were drawn of the natural fize, and if I had not had ocular proof
of it, I could not have believed it pofTible for the moths to come out
of fo fmall a cafe or covering as is here pi6lured. *
On the faine 25th of May, I went to the granary, where, the pre-
ceding autumn I had feen the maggots before mentioned creeping up
the walls, and there I law a number of moths, fome clinging to the
wall, and others flying about. I had brought with me fix glal's tubes,
and, as it was eafy to diftinguilh the males from the females, the
former being fmaller than the latter, I put in each of thefe glafl'es
fome of both fexes.
At my return home, I did'efted three of tliefe females, and, by
the moll accurate reckoning I could make, I found in each of their
bodies upwards of fifty eggs. At another time, I judged that I took
out of another female moth, above feventy eggs. Thefe eggs were
exadlly the fliape of hens eggs, but no larger than fmall grains of
fand. The reft of the moths which I had brought from this granary
and kept alive, laid m.any eggs, and one of them produced to the
number of I'eventy.
I next confidered, whether the moths, which thus propagate the
* This obf.-rvation of the Author is corroborated, and, at the fame time, the a.prarance
can be accounted for, by a circumftanct which was fome years ago communicated to the
tranflator by a curious obferver of the change of aurelias into butterflies and moths, namely,
that immediately after their emerging from the fhell, or covering, which inclofes the n, they
increale in fize fo rapiJiy, particularly in tlic wings, that their giowth may be difcerned by
the eye.
( 29 )
pernicious infe61 I am treating of, might not, by fome means, be
deftroyed in the granaries, fo as to prevent their pro}5agation.
For this purpofe I took a round glafs veflisl, large enough, as I
fuppofed, to hold fix pints of water, and in it I put eight living
moths newly taken. In the orifice of this veHel I fet fire to the fourth
part of a grain of fu!phur, and as foon as the moths began to feel
the vapour, or fmoke of the fulphur, they fluttered about the glafs
with great violence, though but for a fhort time, for they all fell to
the bottom, and after a little motion in their feet, they died. Four
hours afterwards, I took them out of the glafs, and put into it fome
frefii ones alive, in order to repeat the experiment, but while I was
preparing to burn the fulphur, I faw tliem all lie dead, they having
been killed with the bare odour cf the fulphur Vvliich had been left in
the glafs.
From the fize of this glafs, I computed what quantity of fulphur
would be requifite to fumigate a granary twenty four feet long, fix-
teen broad, and eight feet high, and I reckoned that half a pound
would be fufiieient for the purpofe.
After this,. I fumigated a granary, in which were eight loads of
wheat, and a great number of motl-s flying about. For this purpofe
I took two pieces of fulplrur, containing about a quarter of a pound,
prepared in the fam.e manner as is done by wine-merchants or coopers,
to fumigate their wine cafKs. Thefe pieces of fulphur I fufpended by
a brafs wire, in a tall earthen vcflel, with a narrow top, and placed
the vefl'el in an earthen difh, to prevent any danger of fire. This
apparatus I fet in the middle of the wheat, and as foon as the fulphur
began to burn, I retired cut of the granary and fnut the door. In
a large granary two or three of thefe vefl'els might be ufed.
Two days afterwards, I vifited the granary, and then i faw feve-
ral moths ilill clinging to the wall and beams, but before the fumi-
gation, I believe there were ten times as many. And I accounted for
thefe moths being found alive, either becaufe many of the panes of.
( 30 )
glaCs in the windows were broken, through which mucli of the fnioke
of the fulphur had efcaped, or elfe, that the moths which I now faw,
had come out of their aureha ftate after the fumigation was over ; for
I am well aflured, that io long as the moths are inclofed in their
aurciia cafe, or covering, the fmoke of fulphur cannot do them any
injury. Therefore it will be neceflary for thofe who may chufe to
fumigate th^ir granaries in the manner I have recommended, to be-
gin the operation as foon as ever the moths appear, that they may
he prevented laying their eggs, and alfo to continue the ufe of it
fome days, indeed as long as any moths are to be feen, becaufe
tbefe creatures do not all com.e out of their aurelia ftate at the fame
time. The expence of fumigating is no obje6i, for a pound of ful-
phur may be bought for a trifle, and it is in no fort injurious to the
wheat, nor is it prejudicial to tlie health of any perfon, but rather
falubrious.*
Towards the end of fummer, when the maggots quit the wiieat,
and creep up the walls, tliey may eafily be fwept down and dellroyed,
for this infe6l is a very tender animal, and foon killed. And tliefe
precautions being obferved, very few moths will be feen the fol-
lowing year.
Some of the eggs laid by thefe moths I put in glafies by them-
felves, which I carried about in my pocket, others of them I placed
in my ftudy, and I obferved that thofe which I carried about me
were, by the lieat of my body, mucli fooner hatched than thofe
which W'cre in my lludy, for thefe latter were fixteen days before the
maggots crept out of tliem ; but at I'even days end thofe in the for-
mer made their appearance.
One of thefe maggots, when newly hatched, I put into a glafs
tube, tlie infide of which was about the fifth part of an inch wide,
and having placed this before the microfcope, I gave it to the limner
* This opinion is confirmed by Dr. Hodges, and Dr. Me:d, in their Trcatifcs on the PIrgue.
( 31 )
to make a drawing of, but as it was impoflible for him to draw all the
minute parts of it, he drew it without the feet, as is fhewn injig. 8,
KL.* The fore part of this maggot is provided with fix feet, which
fometimss could be difcerned when the animal lay flat on its belly,
and thefe, with part of the body are fliewn atj?:^. 9, MN. In the
hind part are various organs afli fling in its motion. This maggot,
although, when newly hatched it appeared no longer to the naked
eye than is defcribed in the center of the circle at /^. 10, was yet
twice the length of the egg from which it was produced.
As I obferved fome of thele young maggots to be dying, I put
fome grains of wheat into the glafs, and foon afterwards the living
ones difappeared, whence I concluded that they had found their way
into the v»heat, and in three or four days time I faw their excrements
fcattered about the glafs.
I have often contemplated the fliells of the eggs from vvhence thefe
maggots proceeded, and obferved vefl'els in them in the nature of
net- work, which I could not diftinguifh while the eggs were full. A
drawing of one of thefe is given at^^r. 1 1,. RSTV, but as thefe eggs
are exceedingly minute, this drawing was made from a microfcope of
greater magnifying power than that from which the former figures
are drawn. STV is the broken fliell of the egg in the part where
the young maggot crept out.
The moths I have been defcribing are verv pretty obje6ls to be-
hold, the wings, which are four in number, being white, fprinked
all over with black fpots ; and on examining them by the micro-
fcope I found that this whitenefs proceeded from the white feathers
on the wings, and that the black fpots v/ere caufed by other feathers
which were black at the edges. Some thoufands of thefe feathers
* This figure does not feem taken wi.h fo much exaftnefs as is generally found in thofe given
by Mr. Leeuwenhock, therefore the Tranflatorhas caufed a drawing from one of the maggots
when full grown, to be made of the fame fize it appears to the naked eye, and this is to be ken
^\.fig. 1 2..
I faw flicking to theglafTcs in which I kept the moths, which in their
fluttering againfl the glafs or one another, had heen rubbed off their
wings and other parts of their bodies ; and to the naked eye, exhi-
bited the appearance of a vapour or fmoke on the glafs.
Though I examined fome thoufands of thefe feathers, they were
all fo differently formed, that I cannot fay I faw two exactly alike.
Fi'^ 13, A B, CD, EF, reprefents three of the largeft of them, when
feen through the microfcope. At their broad ends, they a^e tinged
with black, and when feveral of them lie clofe together, they exhi-
bit a black fpot. Others of thefe feathers, as 7^-. 14, GH, IK, LM,
are tranfparent, but when lying one on another they produce the-
whitenefs 1 have mentioned. All of them, although fo very minute,
have quills like the feathers of birds, by which they are fixed or
rooted in the membrane that forms the wing, and lo completely
cover it that it cannot be feen.
The feathers, wliich cover the edges of the wings, are much
longer than the others, and of different fliapes ; five of them are
reprefented at^^. 15, RS, TVW, and atjjg. \6, NOPO, arefliewn
a number of the fmall feathers of different fhai:;es.
This maggot, which among us is called the wolf, is not only
mifchievous, by devouring the corn, but it is of that Ipecies which
is found in houfes, and gnaws holes in woodj alfo in boxes and
books, and likewife hides itfelf in woollen garments, eating holes
in them, and at length becomes a flying infedl:^ named as before
mentioned, a moth.
This moth., of itfelf, is very innocent, for while in that ftate, it
.does not, as I could difcover, take any food, but, if not deftroyed in
time, one female may produce feventy maggots, for out of upwards
of feventy eggs, laid by one moth, I only faw one barren ; and in
three others of the eggs, I could difcern the maggots lying dead, by
jeafon, as I fuppofe, that they could not break their fiiells.
1 heard it affirmed, by a corn-dealer, in fupport of his opinion.
( 33 )
that thefe maggots are produced in wheat fpontaneoufiy, that they
arc more rarely found in old wheat than in new ; to which I gave
for anfwer, that when hrll iiatched, they are very imall and tender,
fo that it is difficult for them to pierce the hulkof old wheat, tlie fame
being very dry and hard, and confequently many of them die for
want of nourifhmcnt. This I fully proved by experiment, for I had
three glafles Handing in my lludy, in one of which there were more
than fixty maggots newly hatched. In this glafs I put fome grains
of wheat, one of which v/as broken, or fplit down the middle, and
tliis alone v/as eaten into, the others remaining uninjured, and all the
maggots, except one or two, died ; all which, I had no doubt, pro-
ceeded from this, that thefe grains of wheat ^^'ere remarkably dry and
hard, having been kept for two or three years in a box in my lludy .
and in another of the glafies, wherein I obferved the maggots creep-
ing about on the furface of tlie wheat, without being able to pene-
trate it, I cut feveral of the grains in pieces, and by this means
many of the maggots were kept alive.
Towards the end of the month of September, I received from a
baker a handful of very excellent rye, with many of thefe maggots
in it, all which I put into a large glafs veil'el, and I obferved the
maggots quit the rye and creep up tlie fides of the veflel. 1 then
bunit a fmall quantity of fulphur in it, and in a fhort time they were
all killed.
It may not here be unv\orthy of notice, that, in the glafs tube before
defcribed, and in which I imagined I had put nothing except wheat,
and the caterpillar or maggot, of which I have been treating, I found
a Weevil make its appearance : this creature I kept in the glafs to fee
if any more would appear, and I obferved, that in the winter or in
cold weather it lay motionlefs as dead, but upon applying fome
warmth, it v.'ould revive. At length, after keeping it upwards of
eighteen months, in which time, I did not obferve any more of the
fpecies, it died. E
(• 31. )
Moreover, wliile I was exaniiniiig tlie granary before inentioned,
I faw many very minute animalcules *, no bigger than grains of
fund, creeping up the walls. Some of thefe I brought liome with
me in glafles, and I obferved them to couple together, and to lay ex-
ceffively minute eggs, which eggs, after i'ome time, produced animal-
cules formed like the parents. By this it appears that thefe little crea-
tures propagate their like, without undergoing any fuch change as
is obferved in fleas, moths, flies, and many otlier infe^ls : I think,
however, it is fully proved, that no living creature is produced from
corruption or putrefa6lion.
Indeed, can any man in liis fobcr fenfes imagine, that the moth,
of which I have given the defcription, which is fitly provided by
nature with the means to ])ropagate its fpecies, furniflied with eyes
cxquifitely formed, with horns, with tufts of feathers on its iiead, with
wings covered with fuch multitudes of feathers, all of different
Ihapes, and thefe exa6lly covering the wings in every part ; can this
moth, I fay, adorned with lo many beauties, be produced from cor-
ruption ? For, in a word, in this little creature, contemptible as it
feems to us, there Ihine forth fo much perfe6lion and Ikill in the for-
mation, as to exceed what we obferve in larger animals.
* Mr. Leeuwenhoek has not given any figure of thefe animalcules, but they feem to be
a fpecies of mite; the tranflator has obferved fomeofthe like kind in bran.
Of the spider.
-^1
Jl he following obrervations were made on thofe kinds of Spiders
which are found in gardens ; where they fix their v/ebs to vines,
herbs, and rnrubs.
I have often feen thefe Spiders, when dropping, or falling, as it
feemed, from a tree, flop or fupport themfelves in the midway, by
means of their thread, and I found that this was done by the help
of one of their hind feet, which they continually apply to the thread
as they fpin it. Thefe feet are each of them furnilhed with three
nails or claws, Handing feparate, or apart from each other. Tv^^o
of thefe claws are at the extremity of the foot, and each of them is
formed with teeth, or notches, like the cuts in a faw, growing nar-
rower towards the bottom ; and with thefe they are enabled to hold
fall the thread, in like nianner as the pulley or wheel, uied by clock-
makers, in their thirty-hour clocks, is contrived to lay hold of the
clock-line, by micans of the groove being narrower at bottom.
For the more perfe6lly underfianding this formation, I caufed the
following figure to be drawn.
Plate 11.//^. 17, A B C D E F, reprefents a fmall part of the Spider's
hirid foot, magnified, and at BC D, are fliewn the two claws, or nails,
v/ith the notches or teeth in them, as before defcribed : at letter E, is
feen the third claw, which is defiitute of teeth or notches, but, as I
conceive, ferves for various ufes to tlie animal, and this is always to
be noted, that wlien tiie Spider docs not want to afcend to an heigln,
but only to lay hold of the v.eb it has fpun, it always ufes this claw
for that purpofe.
E 2
( 3S )
The kind of Spider I am now delcribiiig, has the hind part ol" its
body much larger than is lecn in otlier Spiders ; it is provided with
eight longer and two fliorter legs, which fnorter ones are placed in
tlie fore part of its body on each fide of the head, and all furnifhed
with an indented or notched claw as before defcribcd. Some will
have it, that Spiders have no more than eight legs, but this appears
to be a miftaken opinion.
' In thefe Spiders I plainly perceived eight eyes, two of which are
placed near to each other at the top of the head, and, in my judg-
ment, defigned to fee thofe objefts which are above the animal.
Two others of them are fituated a little lower down, in order to dif-
cover all objects in front ; and on each fide of tlic head are a pair of
eyes clofe to each other, and of thefe, the two wliicii ftand forward,
are to take in the view of all objefts lying obliquely, or not ftraight
in front ; and the two which fland backward, are undoubtedly de-
figned to behold all obje6ls behind the animal. And if we confider
that the pupils of thefe eyes are immoveable in the head, we may
eafily conclude, that this number is necefiary, for enabling tlie Spi-
der to behold all circumjacent obje61s, and to go in fearcii of its food.
That the form of thefe eight eyes, and their fituation, may be more
eafilv conceived, I ha\e caufed a drawins; to be made of them at
fg. 18, GHIKLMNO, which l-eprefents a part of the Spider's
head ; P 0, are the two eyes which look upwards, K and L, the two
defigned to view objefts in front, I and M, thofe which take in cb-
je6ls obliquely in front, and H and N thofe which look obliquely
backwards.
I have often heard it faid, that the Spider has a fting, with which,
it is alfo reported, it can kill the toad ; but no one could tell me in
what part of the body this fting was placed, therefore, I concluded
that if there was one, it muft be in the pofterior or hind part, as in
other animals and infeils ; but on examination, I found this opi-
nion to be groundlefs. The Spider is, however, provided with tv.o
( 37 )
orgaris or weapons anfwering every purpofe of a fling, wliicli are
placed in front of its head juil below the eyes, and when not in ufev
thev lie between the two (horter feet.
Thefe weapons or inftruments of offence, which are bent in the
nature of claws, are very fnnilar to the fting of the Scorpion and the
fangs of the *Millcpeda of India, and in each of thefe fangs (for fo I
will call thesn ■ is a Imall aperture, through v/Jiich, in all probability,
a liquid poifon is emitted by the Spider at the time it inflifts the
wound.
\tfg. 1.9, ABCDEFGHIKLM, are reprefented both thefe
fangs as fcen through the microfcope : BC, is one of them when
lying (till, H I K (hews the other, railed to llrike. At C and I, is to
be i'een the fniall aperture'^ I have mentioned, \\ hich aperture ap-
pears the fame on both fides of each fang, and through this we may
reafonably conclude that the Spider ejec^ts its venom. At the letters
EFG, is a double row of teeth, between which each fang is placed
when at reft, and the ufe of thefe teeth feems to me to be for the
lirmer grafping the prey, that when bitten it may not eicape. All
the other parts of thefe weapons or organs which are reprefented in
Jig. ig, were thick fet with hairs, but which it was not thought ne-
cefiary to exhibit in the drav.ing.
I at fevcral times inclol'ed two or three large Spiders in the fa)ne
glafs, and always found that when they approached each other, they
* That is in Englifli, thoufand legs, the name vulgarly given to this animal; the Dutch
call it Duyfent-been, a word of the- fame import.
■j- Dr. Mead, in his c^-lebrated Eflay on Poifons, when treating of the Spider, exprefied his
doubt of this fAdt, by reafon that he could not himft-If difcovcr the aperture, and Air. Henry
B.iker, in his Treatife on the Microfcope, concurred in opinion with the Doflor, that Mr.
Leeuwenhoelc mufl- have been miftalcen in this particular. But in another Treatife*, after-
wards publifhcd by Mr. Baker, he informs his readers, that he had at length plainly perceived
the aperture, and had fiievvn the fame to Dr. Mead, who was much plcafed with the difcovcry.
A tcflimony this, greatly to the honour of our Author.
* Employment for the Microfcope.
( 38 )
"would figlit to that degree, as to be covered with the effiifion of
blood froin their bodies*, which was foon followed by the death of
the wounded Spider. I alfo obferved, that the fmaller Spiders al-
ways avoided the larger, but when two of nearly equal fize ap-
proached each other, neither would give Avay, but both of them
grappled together furioufl}' with their fangs, till one of them lay
dead upon the fpot, its body being as wet with the blood flowing from
the wounds received, as if v.'ater had been poured upon it.
I at one time had a Spider which Mas wounded by the bite of
another in the thickeft part of its leg, and from the ^^•ound there
iffued fome blood, in quantity, about the fize of a large grain of
fand ; this wounded leg, the Spider held up, as unable to ufe it, and
foon afterwards the whole leg dropped from its body : whenever i.he
breaft or fore part of the Spider was wounded, I always obl'ei ved the
wound to be mortal.
I had imagined, that when a Spider applied its thread either to fome
foreign fubftance or to another thread, that the thread newly fpun
mull: be covered with fome vifcous or glulinous m.atter by w hich it
became faftened, in like manner as we obferve in Silk-worms
threads. But I now found that the Spider cannot fix its tliread to any
thing, without imprinting the hind part of its body on the place, by
which preflure, it emits an incredible number of exceflively fmall
threads, diverging in every direction, from wlience we may conclude,
that as foon as the threads are expofed to the air, they lofe their \ il-
cofity or glewy quality.
When I at finl: began the difie6lion of the Spider, and endea-
voured to difcover the vifcous or gummy fubfiance from v:hence
thel'e threads proceed, and could not fatisfy myfelf in that particular,
1 was alloniflied, not being able to conceive how, from fo moid a
* If any reader fliould be difpored to try this experiment hp miift not cxpcil to fee a red
liquor iiTuc frc.m the wounded Sjiidcr. For the circulating fluid in many infects is clear or
•caiourlwfs, though as flay to be dcnumir.ated bloi-J, uS th.-.c wiilcii flows in the veins of an;-
m:ils.
( 39 )
body as this creature's, there could in fo flicrt a time, be produced
threads ftrong enough to bear the weight, not only of one, but of
lix Spiders at a time. And upon endeavouring to difcover the tex-
ture of the threads, I could at that time perceive no more, tlian that
tlie fame thread appeared in fome places to be one and entire, and in
others, to be compofed of three, four, or more threads ; and though
I often endeavoured to obferve thofe threads immediately as they
ili'ued from the Spider's body, I could not obtain a perfect view of
them, notwithilanding which, I did not doubt, tl^.at vv'hat is commonly
fuppoi'ed to be one thread, is, in fa 61, compofed of many.
I determined therefore, ib to fix a Spider on its back, that it could
not move the hind part of its body ; and this leing done, I contrived
with a fmall pair of pincers to draw out from th.e body, that fmall
part of the thread which proje61:ed from the organ or infirumentfrom
which the threads proceed, and then I perceived a great number of
exceeding fmall threads iffue forth, which, when at about one or
two hairs breadth diflance from the Spider's body, united in one or
two threads, and that in this manner the larger threads were com-
pofed.
Not content with thefe obfervations, I fat about devifing means of
keeping the threads feparate, as they iffue from the Spider's body, fo
that I might be able to give fome reprefentation of their inconceiv-
able finenefs, and at three feveral times I uicceeded herein to my
wifli. But yet, this finenefs cannot by any efforts of the pen or pen-
cil, be adequately defcribed. For upon applying the utmofl: magni-
fying powers of the microfcope, threads are difcovered fo exquifitely
flender, as almoft entirely to efcape the fight, I have fometimes
endeavoured to count thefe threads as they iffued forth, but always
without fuccefs.
The Limner, to whom I exhibited this obje6l by the microfcope,
declared, that it was not in his power to give a true drawing of it
( 40 )
with tiie pencil, but tliat by an engraving, it nii^lit in fi)nie nieafiii-o
be rcprefented. This is done in ^"^.20, MNOFQ, being a portion
of thcl'c threads, as magni' ed by the microfcopc, and pichired fepa-
rate and diliini:t from each other, as they iflued from the body of the
iininud. Thefe feemed to me to ifliie from two of tlic organs, which
I fliall prefently defcribe.
If v,e dniy confider tliat the threads of Spiders, whicli to the
naked eye feem to be lingle, are compofed of maoy fmaller ones,
and tb.at they thence acquire the flrcngtli we obferve tlicm to have,
we fliall more than ever be afi'ured, tliat no flexible bodies (exce])t
thofe made of metal, the component particles of which are, by the
force of fire, molt clofely compacted or knit together), can have
any great (trength or toughnels, iinlefs they are compofed of ob-
long parts laid fide by fide, and that their ftrength or toughnefs will
be greater where thefe oblong coinponent parts are twilled together,
or made to cohere by fome glutinous matter, as are fpun filk, linen
garments, ropes and the like. And this is the reafcn why all tlie
fing'e threads of flax are very tough in proportion to their fize, for
each of them is compofed of dill fmaller particles or fibres, which are
not only joined together by a certain viicous or gunnny matter, but
are alfo furrounded with a coat or bark, as it may be called, whereby
their inward component fibres are rendered ftill ftronger
Again, if we advert to the great number of excefi[ively flender
threads, proceeding, all at the fame time from the bod}' of the Spider,
we muft acknowledge that this kind of formatioii is neceflary, for
were it a fingle thread which is fpun by this creature with liich ce-
lerity, the hquid matter of which it is formed, could not on its expc-
fure to the air, become a iblid fubfiance fo quickly as thefe lefl'er
threads ; an hundred or more of which, taken together, do not in my
opinion equal the hundredth part of one of thofe hairs I can take
from the back of my hand.
( 4.1 )
In a word, the inlcrutable power and vvifdom of the Ahnighty
Creator, are manifeftly difplayed in the formation of fuch a thread
as the Spider's, the wonderful make of which is feldom obferved,
becaul'e the finenefs and delicacy of its texture are not difcernible by
the naked eye.
Upon beholding the exquifite flendernefs, and alfo the multi-
tude of thele threads, I was ftruck with aftonifhment, upon confider-
ing how wonderful muft be the organs in a Spider's body to produce
fo many, and at the fame time all diftindl: from each other. And
although I never expedled that I fliould be able to dive into this fe-
cret of Nature, yet, upon diilefting the hind part of one of the largefl
Spiders I could procure, and attentively examining it, I at lengtli.
with the greateft admiration, perceived a great number of excelTively
fmall organs, from each of which, one exquifitely fine thread pro-
ceeded, and thefe were fo many, that I thought their number muft
at leaft exceed four hundred. They were not all placed clofe toge-
ther, but in eight diftin6l fpots or compartments, ib that if the
Spider ufes all thefe organs at the iame time, eight feveral threads
may be formed, each of which will confift of a great number of
fmaller ones. Again, thefe fmaller threads differ in fize, for one of
the organs will be feen to fpin a tliread twice as large as the next
adjoining to it.
If any perfon examines by the microfcope that part towards the
extremity of the Spider's body, from whence its thread proceeds, he
will obferve the fpot to be, as it were, furrounded by five feveral pro-
tuberances or rifmgs, each ending in a point, and altogether form-
ing a kind of enclofure ; but from the anterior or forwarded: of thefe
five protuberances no threads proceed. The other four, on their
outer fides are tliick fet with hairs, fo that all the fm.aller organs
defiined to fpin the threads, are fituated towards the infide, the rea-
Ibn of which, I take to be, that they may be preferved uninjured,
F
( -I'-^ )
when the Spider is creeping into lioles, uhere it does not want to
Ipin its web, or while running along the ground, or after its prey.
When thefe lall mentioned four protuberances are put afide from
each other, there will be feen in tlie middle or fpace between them
four fmallerones, each furnilhed witli the like organs for fpinning
threads, but lefler in fize and fewer in number.
Thcfe organs for fpinning, being by this means all exi)ofed to
view, exhibit the appearance, as it were, of a field, thick fet with
an incredible number of pointed parts, each producing one thread ;
but thefe pointed parts are not made gradually tapering from the
bafe to the point ; they are formed, as if one were to imagine a
fmall reed fomewhat tapering, having a flill fmaller one joined to its
taper end*, and this latter terminating in a point, which point, in
thefe organs I am now defcribing, is as fine as imagination can con-
ceive.
Now if we lay it down as a fa6l, that a young Sj^ider which is
feveral hundred times Imaller than a full grown one, is furniflied
with the fame organs as the larger, and that, as the Spider, fo the
organs do by degrees grow proportionably larger, the necedary cor-
clufion is, that the threads fpun by a young Spider, are many hun-
dred times finer than thofe fpun by one full grown, which exquifite
flendernefs, it feems beyond the power of the human mind to form
a true idea of.
I have given a reprefentation of fome of the organs, by which thefe
incredibly fmall and numerous threads are fpun, as nearly as the
Limner was able to draw them, when feen by the microfcope. And,
^t fig- iii, RSTV, exhibits one of the four external parts or protu-
berances I have been defcribing ; this part, including all which with
it is reprefented in the figure, was not in its natural fize lb large as
a common grain of land, from whence fome judgment may be formed
how minute muft be thefe orgaiis, and how exquifitely fine the
threads w-hicli iflue from tliem.
* See fig. 22.
(. 4-3 )
In this figure, that part which is inai'ked witii the leiter W, was
covered with as many organs, and thofe placed as clofe together,
as are reprel'ented hetween the letters R and S, but as theie latter,
ftanding direcHy in front, could not by any means be diltiiictly
fliewn in the drawing, I ordered that fpace to be left vacant : the
part which is out of fight, was not covered with thefe organs but
with hairs.
While I held this objecl up to tiie Limner's view, I turned round
the different parts of it, that he might declare how many of tiic
organs for fpinning tlie threads, in his judgment, it contained, upon
the view of which, he was confident that there were above one
hundred,
I have before mentioned, that fome of thefe organs appeared to
me to be larger than others, and that I fuppoled their ufe was for
fpinning the larger threads. One of tliefe, as it flood between
two fmallcr ones, I placed in view of the Limner, dire6fing him to
make a drawing of it. This is fecn at fg. 32, C F, and in the fame
figure, at the letters ABandDE, are reprefented the two leller
organs, from one of which, a thread is feen to ifliie.
After this, I took a fmall Frog, whofe body was about an inch and
an half in length, which I put into a glafs tube together with a large
Spider, in order to fee the a6lions of thefe two animals when brought
togetiier ; and I obferved the Spider pafs over the Frog without
hurting it, though with its fangs difplayed as if to attack the Frog.
Upon this, I caufed the Frog to fall againft the Spider, wlio, there-
upon, ftruck his fangs into the Frog's back, making two wounds,
one of vv'hich exhibited a red mark, and the other a purple fpot. I
then brought the Frog to the Spider a fecond time, who, thereupon,
ftruck his fai:gs into one of the Frog's fore feet, whereby fome
few of the blood velTels were wounded. And having provoked the
Spider a third time, he ffruck both fangs into the Frog's nofe»
F 2
( 4i. .)
prefcntly after wiiicli, I took the Spider cut of the glafs. The
P'rog, thus wounded, fat without motion, and in about the fpace of
half an hour, it ilretched out its hind legs and expired.
The next day I brought another Frog, about the fame fize as the
former, to the fame Spider, but though it was twice wounded, I did
not perceive it to be injured thereby, perhaps becaufe the Spider's
bite may not be fo venomous in our climate as in warmer regions, or
clfe, that the poifon of this Spider might have been exhaufted by
former attacks ; the Frog I threw back into the water whence I had
taken it.
Towards the end of 06iober, I took feveral of the largeft Spiders
tliat cou.ld be got, and placed them in glafles apart by themfclves, in
order to wait for their laying eggs, which I purpofed to open, and
examine the contents. Two of thefe Spiders, after being confined
ten or twelve days, I found had laid their eggs, and enveloped them
in fo thick a web, that I was aftoniilied to behold it, confidering that
it had been fpun in a few hours fpace.
Some of thefe eggs I opened, and found the infidcs to be of a
3-ellowilh colour ; the form of each egg was almoR round, and
nearly the thirtieth part of an inch in diameter, and the whole collec-
tion of eggs laid by one Spider compofcd a rounding figure, almoft
fpherical, nearly half an inch in diameter, from whence may be com-
puted how great a number of eggs the Spider lays. And one would
almoft think it impoflible for lb many to be contained within this
creature's body ; fmce upon viewing them with the naked eye, as
they lie together in regular order, they occupy a larger fpace than
the fize of the animal itfelf. But it muft be confidered, and it is
what I have often experienced in opening Spiders, that the eggs while
within their bodies are not of a globular figure, but being very foft
they lie comprefled together, and therefore are of divers fliapes, but
as foon as emitted from the Spider they alliunc a fpherical form, by
( 4.5 )
reafon of the equal preniire of the atmofphere on every part of them ;
and when of this round figure, being placed in exa6l order, fide by
fide, and only touching each other in a point, they mufl neceffarily,
to our view, occupy more fpace tliat they did while in the animal's
body.
I at firfl: was not able to conceive by what means the Spider could
place its eggs fo exadly in the centre of the web, but now I was
fatisfied in that particular, for while I was obferving a third Spider
which was fixing a web to the glafs in order to lay her eggs in it, I
faw that firfl flie made a kind of thick layer of threads, and fafiened
them to the glafs before flie began to lay one egg ; and it was moft
worthy of remark that this layer or llratum was not flat, but curi-
oufly made with a roundilh cavity. In about tliree quarters of an
hour's fpace, upon again obferving the Spider, I faw that this ca-
vity was not only filled with eggs, but that eggs v.'ere piled up above
the edges of it to the fame heighth as the hollow of the cavity below,
and the Spider was then bufied in fpinning a web to enclofe the eggs
on every fide. For this purpofe flie employed not only the hind part
of her body from whence tlie threads were fpun, but her two hinder
feet, with which fhe placed the threads in due order. And now all
the organs ufed in producing the threads appeared in view, each of
them in the a6l of emitting its particular thread. I alfo obferved the
Spider elevate the hind part of its body about the breadth of a ftraw,
and then fix the thread which by the elevation had been drawn out to
that length, to the web which was already fpun about the eggs.
I was very defirous to fee a Spider in the a6l of laying its eggs,
which at lenfftli 1 obtained a fisfht of, and obferved that tiiev were
not emitted from the fame part as is ufual in all other minute ani-
mals ; but from the fore part of its belly, not far from the hind legs,
and near the place, I obierved a kind of little hooked organ, hand-
fomely fnaped, which I had often before fecn in tliis animal, and
( 46 )
could not imagine for what purpofe it was dofigned ; but now I
perceived, tliat it extended over that part whence the eggs iiTued,
and I therefore conjectured that its ufe was to depofit them in regu-
lar order within the web prepared to receive them. To give fomc
reprcfentation of thefe parts, I caufed a drawing to be made of a
middling (ized Spider, lying flat on its back, with the legs contracted,
as if it were dead. This i.s lliewn mfg. 23, ABC, and near to letter
D is the hook juft mentioned.
This hook I then leparated from the Spider's body, and placing it
before the microfcope I delivered it to the limner, that he might
make a drawing of it as it appeared to him. This drawing is given
a.tjig. 24, GHIK, and therein between the letters I and K, certain
folds or wrinkles appear, this organ being fo formed as to have a
greater extent of motion and action than ufual. The letters E F
denote that part which was joined to the Spider's body.
On the firft of January, I put fome Spider's eggs into a glafs tube
which I conftantly carried about me, in order to difcover whether by
the warmth I imparted to them, they would be hatched fooner than
the ufual time, w'hich is in the fpring ; and on the 17th of January
I faw above twen.ty five young Spiders compleatly hatched, and as
many more half way out of the eggs ; and in the evening of the
fame day I counted above an hundred and fifty young ones. Tiie
next day, the number was not incrcafed, for the reinainder of tlie
eggs, to the number of fifty, or thereabouts, were either barren, or
the young Spiders were dead within them.
Upon expofing the glafs tube at this cold feafon, to the air for
about a quarter of an hour, the young Spiders lay without motion,
but upon applying fome warmth to it, they began to move, and the
greater number of them crouded themfelves together in an heaji,
after the manner o[' bees, within the web where the eggs Had been.
On the 21ft of January I could difcern eight eyes in each of them.
( 47 )
which till then had not been vifible, and on the 2.5th of January they
began to fpin webs in the fame manner as full grown fpiders.
I iiad hitherto been at a lofs to conceive how this 2:reat number of
young Spiders could be fupplied with n jurifliment, confidering that
the natural food of this creature is the fubflance of other infe6ls ; but
I now perceived that they had fed on the barren eggs which had been
left in the glafs, and they afterwards devoured one another till they
were reduced to a very few in number.
I have often compared the fize of the thread fpun by full grown
Spiders with a hair of my beard. For this purpofe I placed the
thickell part of the hair before the microfcope, and from the moft
accurate judgment I could form, more than an hundred of fuch
threads placed fide by fide could not equal the diameter of one fuch
hair. If then we fuppofe fuch an liair to be of a round form, it
follows that ten thoufand of the threads fpun by the full grown
Spiders when taken together, will not be equal in fubftance to the
fize of a fingle hair.*
To this if we add that fourf- hundred young Spiders at the time
* This is found by multiplying the number of Spiders' threads, conftituting the diameter
of the hair (which the Author computes to be one hundred) into itfelf, the contents of
cylinders (which round threads may be called), being in the fame proportion as the fquares
of their diameters —
therefore 100 diameters of the thread
multiplied by the fsme number 100
the fquare will be 10,000 the proportionate fize of the hair,
and this being multiplied by 400 the fuppofcd bulk of a young Spider com=
4,000,000
pared wiih an old one, gives four millions, the proportion afligned by the Author to the
young Spiders' threads.
The Author's manner of computing thefe very minute dimenfions, is fully explained in
the Introduilion,
f The difference in the fize of garden Spiders in Spring and Autumn, muft have been
noticed by almoft every one, and the Author in his computation, confiders them as fpheri-
( 48 )
Avhen they begin to fpin their webs, are not larger than a full grown
one, and that each of thefe minute Spiders polTefT'es the fame organs
as the larger ones, it follows, that the exceeding fmall threads fpun
by thefe little creatures, muft be ftill four hundred times flenderer,
and confequently that four millions of thefe minute Spiders' threads
cannot equal in fubftance the fizeof a fingle hair. And if we farther
confider of how many filaments or parts each of thefe threads confifts,
to compofe the fize we have been computing, we are compelled to
cry out, O what incredible minutenefs is here ! and how little do we
know of the works of Nature !
I never could procure a fight of thefe animals when coupling to-
gether, either in the gardens or fields, nor when inclofed in glades,
for I always perceived the female to run away at the approach of the
male, and having at one time inclofed three male Spiders with a
fem.ale in one glafs, the female flew at the males with fo much fury,
and wounded them to fuch a degree, that blood iffued from their
legs and feet. Hereupon I killed the female, and the next day I faw
two of the males lie dead, and the furvivor employed in devouring
the dead female.
Thefe are the chief of my obfervations on the Spider, an animal
held in fuch deteftation by many, that they dread even the fight or
approach of it, but in which we find as much perfciiion and beauty
as in any other animal.
cal bodies, which according to the rules of arithmetic, are in the fame proportion to
each other as the cubts of their refpeiltive diameters. Thus, if a young Spider's body is a
feventh part of the diameter of a full grown one, the latter will be 343 times the bulk of the
former, if an eighth part, 5 1 z times. The proportion here afligneJ by the author, is nearly
the medium between thefe two.
Of the silk WORM.
1 HE Royal Society having rccominended to my examination, tlie
fruitful and barren eggs of the Silk- worm, I procured a number of
tliofe eggs, which had been lately laid by the Moth or Butterfly
produced from that infc^l ; this was about the beginning of the
month of September. Thefe eggs, when firft laid, were of a yel-
lowilh colour, which in about two days time affumed a reddilli call,
and at fix days end they appeared to the naked eye of a liver colour,
feveral of tliem I opened, by taking off the upper part of the
fliell with as light a touch as poflible, and in every one of them I
obferved an exceeding fmall and delicate membrane, which to the
naked eye appeared blackifli, but on examining it by the microfcope,
I found the real colour to be violet, but where the violet particles
compofing it lay clofe together, they afiumed a blackifli appearance.
Tliis membrane lay next to the fhell of the egg, and I imagined,
that within it the future Silk-worin would be formed ; and in tiie
part where this membrane was joined to the fliell, I faw a minute
Ipeck or fpot, which I concluded to be the vital principle, and the
rather, as this fpeck was wanting in thofe eggs whicli I found to be
afterwards barren ; and it is further to be noted, that in the barren
eggs no fuch membrane as I have mentioned was formed, nor did
they change their original yellow colour. This membrane in a fliort
time extended over the whole infide of the egg, and being feen
through the fhell, which is tranfparent, caufed it to appear of a
Muifli colour.
Some of thefe eggs, which were fix weeks old, I put into a flat
G
( 50 )
fcrewed box, which in the day time I carried in my pocket, and at
night placed befide me in bed, tliat they might continually be kept
warm ; and in another box of the fame kind, I put fome more eggs,
three weeks old, and thefe my wife (who was always very warmly
clad) conftantly carried in her bofom. This we did, to try the ex-
periment, whether it were poflible to promote the growth of Silk-
worms in the autumn.
In the month of Oftober I opened fome of the eggs which I had
thus kept by me for about a month, and in one of them, I obferved
aininute Silk-worm, about the thicknefs of an hair, and proportion-
able in length, but I was not able to diftinguifli any particular parts
in its body. In the fpace of ten days more, I found larger worms
in the eggs, whereupon, I opened fome of thofe which my wife had
carried about her, and in thole, I law Silk-worms, MJiich by the
microfcopc, appeared as large as one's finger, and thefe 1 propofed
to have given drawings of, but the animals foon drying, and all the
moillure in the eggs evaporating, they entirely loft their figure, fo
that neither the head nor tail, nor any other parts of their bodies
could be difiinguiflied, although I had very plainly feen them when
the eggs were firft opened.
After this, I from time to time opened others of thefe eggs, but
I could not perceive any farther growth in the aniiiials, and at length
all the moifture in the eggs fo dried away, that they loft their Ihape
and became flattened.
In the beginning of May, in the following year, I opened feveral
of the eggs which had remained all the winter in my ftudv, and
then I obferved minute Silk-worms within them, and a kind of glo-
bular particles lying clofe to them, which I judged would afterwards
be formed into the limbs of the animals.
Towards the end of this month, the Silk-worms increafed in
growth very rapidly, fo that on the sicth of May, upon opening fe-
veral of the eggs, I could perceive, not only feveral parts of each
{ 51 )
animal's head, but alfo a great number of fniall vefiels in it wliich
branched out into others extending all over the body, particularly to
thofe parts where I could perceive the claws begin to appear, and
which, therefore, I concluded, were nourilhed by thofe veflbls. In
fliort, I faw fuch multitudes of veffels, with their branches, all of a
blackifli colour, as is not to be conceived, for when thefe branches
became beyond meafure flender, they loft tlieir dark tinge, and at
length became invifible. And I can fafely fay, that I do not think I
have feen fo many arteries pi6tured in the drawing of an human
body, as appeared in thefe obje6ts, which I fliould have given a
drawing of, but the moifture in thefe minute veffels dried fo quickly,
that they "loft their figure, and could no longer be diftinguiflied.
On the 31 ft of May, I opened feveral more eggs, and faw that
many of the Silk-worms in the fpace of the laft twenty-four hours
were lb much grown, that they appeared compleatly formed, for I
could not only fee the head perfeftly formed with all its parts, but
alio all the claws and limbs, and the body every where covered with
hairs : upon opening thefe Silk-worms, I faw the inteftines, and now
the membrane, which hitherto had inclofed the animal, was difap-
peared, the fubftance thereof by this time having palled into its
body, which had aflumed a blackilli colour, but the head was parti-
cularly black, and I perceived fome motion in the animal when taken
out of the egg.
The next morning, upon opening more eggs, each Silk- worm
which had lain in a round pofture within, immediately extejided
itfelf and crept about, ^ and I found that all the moifture which I had
hitherto obferved in the eggs was gone, it having palled into the bod}''
of the worm, -which was perfe6tly dry. In tlie afternoon of the fame
da}^ I obferved that feveral worms had crept out of the eggs placed
in my clofet, whereupon I fat about examining the remainder of
thofe eggs, chufing fuch of them, wherein the formation of the ani-
G2
( 52 )
mal appeared to be leafl advanced, \vhereas before this I Iiad opened
the mod perfect ones : and thefe I found in the fame forwardnefs of
growth as the eggs I had opened on the 20th of May, and by this
time ail the dark coloured bodies of the animals, efpecially the head,
miglit plainly be difccrned tln-ough the tranfparent fliell.
This rapid formation of the Silk-worm, and its motion within the
egg, excited in me the greatefi: admiration, and if I had not profe-
cuted tlie obfervations I have been relating, I fliould have thought
it abfolutely impofllble : for, in the preceding autumn, I had placed
thefe eggs in a much greater degree of heat than they were now ex-
pofed to, and yet I could not at that time promote the perfed forma-
tion of tlie animals within them. And, from my prefent obferva-
tions, I was led to conclude that it has been an eOi^ntial propert}^ of
this creature, implanted in its Ipecies at the firft creation, that the
vital principle mull lie fhut up in the egg for more than the fpace of
fix months, without any augmentation of its fubftance, except in the
formation of that part which is to ferve firft for the defence and pre-
fervation, and afterwards for the nourifliment and increafe of the
animal, and this is the membrane or fkin I have before defcribed ; and
that were it not for this provifion made by nature, the whole fpccies
of the Silk-worm would be liable to pcrifli in one year : for if a warm
i'eafon in autumn fliould caufe the worms to be excluded from tlie
eggs, the fucceeding cold and rains muft prove their deftrudtion.
I obferved that the Silk- worms always came forth from their eggs
in the morning, and not in the afternoon. To afcertain this, on the
laft day of May, in the evening, I counted the eggs I had then left,
which I found to be about two hundred. The next day, namely, on
the firft of .lune, at fix in the morning, ninet} -feven Silk- worms had
come out of their eggs, and the fame day at dinner-time, or about
one o'clock, thirty-two more. In all the afternoon, althougli the
atmoJ'phcre was warm, only one made its appearance ; but the next
( 53 )
day, at feveii in the morning, forty more were excluded from tlieir
ecrgs.
r always found, that the opening in tiie fliells, through which the
worms crept forth, was blackifli about the edges, and, as I could not
conceive this blacknefs to be caufed merely by the touch of their
bodies as tliey crept tlirough the opening, I carefully obferved the
animals at the time they were employed in biting or gnawing open,
the egg, and I always perceived, that in doing this, they frequently
emitted a blackifli watery humour or liquid from their mouths, with
which they moillened the fliell in that part where they were biting it,
and this not merely on the infide, for when they had made the aper-
ture large enough for them to emit this liquor on the outfide, they
then moiltened the ihell both within and without. I alfo obferved, that:
when the worm was about moiflening the fliell, it ceafed biting or
gnawing for a fliort time, until (as I fuppofe) it had brought into its
mouth a portion of the liquid for that purpofe, in like manner as
oxen, while chewing the cud, defift at intervals for a fliort fpace,
until they have produced a frefli portion of their food from their fto-
machs.
From hence I concluded that without this kind of liquid, it would
be impoflible for the young Silk-worm to open to itfelf a paflage
through the fliell of the egg. And I faw that the animal was very
fparing in the confumption of this liquid ; for in that part where it-
had moillened the fliell, it continued to bite or gnaw (without mov-
ing to a frefli place), until (as it appeared to me) it had eaten or
taken into its mouth the liquid, and the bitten or fcraped-olFpart of
the fliell. At which inconceivable perfe6f ion in this little creature, I.
was ftruck with aflonifliment, and I drew from it this conclufion in
my mind, that not only the Silk-worm, but other creeping infe^fs,
when come to maturity in their eggs, do emit fome liquid niatter,
from their bodies, in order to foften the fliell in that part wliere they
are endeavouring to break forth, and poflTibly this liquor may have in
( 5i )
it fome acute or corrofive fait, fitted for foftening the fliell of the
egg-
I cannot quit this part of the fubje^l, without exliibiting the for-
mation of the Silk- worm's egg, becaufe the feveral particles of which
it confifls, are fo firmly and clofely united together, that they pre-
I'erve the liquid fubfiance within the egg many months without the
leaft. evaporation.
Plate II. fg. 25, FGH, is the fhell of the Silk-worm's egg, opened
by the animal, as it appeared to the limner through the microfcope ;
G H, is part of tlie aperture which the worm, by biting or gnawing,
opened for itfelf, and through which it crept out of the fhell.
Some years after the precetling obfervations, I further profe-
cuted my enquiries by obferving the Silk-worms as they advanced in
growth, which I could eafily do, having two mulberry trees in my
garden, which fupplied me with food for the worms, of which I had
three or four hundred.
I have often by the microfcope examined the cuticle or thin fkin
which is fhed by thefe infe6f:s the * lafl time before they are full
grown, and particularly the more folid part of it ^^•hich covers the
head ; and with great wonder, I beheld in it all the organs or mem-
bers with which the head is furniflied, and particularly I faw a num-
ber of eyes difpofed on each fize of the head, in fit order to enable
the animal to fee every objeil around it : further to examine which,
I have feveral times cut off the heads of full grown Silk-worms, for
otherwife they were in fuch continual motion, that I could not clearly
diflinguifli thefe eyes. When the Silk-worms were changed into
aurelias, I faw the fkins of their heads and the reft of their bodies,
which they had put off" on the change, and upon examining thefe by
the microfcope, I always found the horny coats of the eyes in their
caft-oft' fkins. Several parts or pieces of the head with the eyes in
» Silk-worms fiicd their fkins four feveral times, before they begin to fyht their cone or
covering.
( 55 )
them, I placed before the microfcope, and delivered them to the
limner, that he might make a drawing of one of them.
Fig. 2.6, ORSTVW, reprefents one fide of the Silk-worm's head,
with fix eyes placed therein; on view of which, it plainly appears
that the eye marked with the letter O, is defigned to view obje6ls
diredtly in front ; that marked R, to look a little obhquely forwards,
and at the I'am.e time upwards ; the eye marked S, to look on one
fide, and at the fame tune a little upwards ; that marked T, to look
rather backwards, and alfo obliquely upwards ; the eye marked V,
to look entirely backwards ; and that marked W, downwards. And,
confideringthat the eyes of thefe creatures are immoveable, the num-
ber and pofition of them as before defcribed (fix on each fide), are
the bell calculated for enabling the animal to fee all circumjacent
obje61s.
At the fame time, I obferved the teeth or pincers with which the
head is provided, and with which this animal bites or chews the
leaves it feeds en ; a row or fet of thefe teeth is placed on each
fide of the head, and they moft exa611y fit into or correfpond with
each other. Fig.^j, ABCDE, reprefents thofe teeth which were
placed on the right fide of the head, and here may plainly be feen
how each tootli has a thicknefs or rifing about the middle of it, in
order to give it ftrength, whereas the parts of the teeth between D
E, are exceedingly iharp and fine, in order more eft'edlually to cut
or chew the leaves : and each of thefe teeth has the fame thicknefs
or rifing, both on the infide and outfide. The part reprefented at
ABC D, appears very thick in proportion to its fize, but upon more
narrowly examiriing it, I found that this thicknefs did not confift of a
folid bone, but was hollow within, which cavity probably had been
filled by fome kind of mufcle. At A and B, appear two round boney
parts, which in my opinion fit into hollow fockets in the head, fo as
to give the teeth free and fufficient motion.
i 5« )
When I firft examined the Silk-worni's thread by the niicrofcope,
k Teemed to me not to be of a round form but flat, for the fame
tin-ead appeared in fome places four times thicker or broader than
in others ; I alfo thought, that each of the threads \vas double, or
compofcd of two others, forafmuch as the middle of the thread
always feemcd darker than tlie reft, and the whole aj^peared, as if
one were to fuppolb, two tranf[)arent threads lying clofe and parallel
to each other, and glued or I'aftened together, and each of thefe two
threads not to be fo pellucid at the fides as in the middle.
I next confidered with myfelf, whether thefe fmgle threads might
not be compofed of many fmaller ones, and having at length found
jneans to break or fcparate them into very fmall fragments, I plainly
percei\'ed each of tliem to be compofed of a number of exceirively mi-
jiute filaments.
Farther, I placed a Silk-worm which was beginning to fpin its
ball or covering, in a glafs tube, large enough to give the animal
liberty to move and turn itfelf about, and I obferved it to fix the
thread in various places, fometimes to tlie glafs and afterwards to the
threads already fpun, by means of a certain glutinous or gummy
matter, with which the threads arc fmeared when they firft iilue
from the animal's body. In the progrefs of its fpinning or forming
its ball or cone, the Silk- worm frequently changed its pofition, and
carried the thread by various turnings and windings in every direc-
tion, it being implanted in this creature by nature, always to form its
cone or web of an equal fubftance and ftrength in every part next its
body.
Upon examining this cone or ball of filk by the microfcope, I per-
ceived in hundreds of places, that the threads of which it was com-
pofed, were not fingle but double threads, and this was more parti-
ailarly dillinguifliable in thole places where they were bent in a very
Ihort elbow or turning in their fixure, either to the glafs or to one
another. This is explained at j^^g-. 28, ABCD, which reprefents
( 67 )
a very fmall particle of the Silk-worm's thread, and' this is here
feen to be formed of two others, wliicli, for the greateft part, are
joined together as at letter A, but where tliere is a fliort turning or
winding they are feparated, and appear in t^^o parts. This double
thread remains united, by means of the vifcous or gummy matter be-
fore mentioned, until, by being immerged in water, the gum is
dilTolved.
Now, if we conflder that the Silk- worm's threads are not round
but flat, we fliall prefently difcover the reafon why no lubftance,
whether of wool or hen^p, how fine foever it may be, can be formed
into cloths or ilulFs, that will compare with filken garments in the
gloffinefs of their appearance. For, the flat furfaces of the filkea
threads, refiedl the light more copioufly and ftrongly, producing their
glittering or glofly appearance, whereas the light which lliines on
fmall round bodies is very little reflected from them.
In order to exhibit the flatnefs of tlieie double threads more
plainly to the limner, I twifted fome of ihem a little, and then plac-
ing them before the microfcope, I caufed him to make a drawing
thereof. One of thefe threads is Ihewn at Jig. 29, EFGHI, and be-
tween the letters FG and HI, it is pictured as feen obliquely, prov-
ijig that the threads as fpun by tiie worm are not round but fiat ; they
ai-e likewife fo tranfparent, that one thread can eafily be feen through
another which is placed upon or over it.
Let us but attentively confider the make and compofition of fuch
a thread as the Silk-worm's, bearing in mind alfo, how wonderful
mufi: be the fi:ru6lare of the creature's body from which thei'e double
threads are produced, each of which again confifls of a great number
of oblong particles or fmallcr filaments ; and when we further refle6l
that from fo moifl and watery a body as is the Silk-worm's, fuch
llrong and tough threads are produced, capable of being applied to
tlic many purpofes we continually experience, who, upori feeing all
H
( 58 )
thi.<5, can refrain from exclaiming with me " How infcrutable and
incomprelienfible are the hidden works of Nature \"
The filken cafe or web of which I am now treating, and which the
indiiflry and ingenuity of mankind has converted to fo many ufeful
purpofes, is conftru6led by the animal for no other end than that,
when its change into a cliryfalis or aurelia approaches, and it cannot
then be concealed under the leaves of the trees, nor can during the
time of its change adhere to any thing, nor even change its place, and
during all that time lies as it were motionlefs, it may be preferved
from becoming a prey to birds ; and this I am well convinced is the
cafe with all infe^ls of the caterpillar kind, which, when they are full
grown, and their change approaches, wrap themlelves in fome kind of
web or covering.
But my chief objeft, in all thefe my obfervations, was, to difcover
as much as poflible the nature of that organ from whicli thefe two
threads proceed, and by what contrivance they are joined ib clofcly
together : the common opinion refpe6ling whicli threads is, tliat they
ifliie from the animal's mouth. For this purpol'e I found it necefiary
to fix a Silk-worm on its back, and then the organ, which is placed
below the mouth, appeared in fight. Fig. ^o, ABC, exhibits this
organ. The parts marked DE and FG are placed below the mouth,
and the organ from which the threads ifliie is fituated ftill lower.
While the limner was making this drawing, fome part of the teeth
appeared in his view, which he alfo included in the figure, at the
letters HI K, and this was done, more clearly to prove, that the
threads do not proceed out of the Silk- worm's mouth, as is the vul-
gar opinion.
After I had dil'covered the particulars above enumerated, I endea-
voured to inveftigate the matter or fubfiance from which the threads
are formed in the body of this infe6t. For this puri)ofe I cut oflftlic
heads of feveral Silk-worms whicli had begun to fpin their web or
cone, and then I faw, befides the other internal parts, two oblong
( 69 )
and round bodies four times folded or doubled together, which I took
out of the animal's body. Thefe parts were almolt twice the length
of the Silk-worm, and at one end, the fituation of which I conceived
WHS in the head, they terminated in a point, and fometimes I faw
ilTue from this pointed end, an excefnvcly flender thread, four times
the length of the Silk-worm.
Thefe organs, or rather veflels, in the thickeft parts of them, were
of a red colour, yet when examined by the microfcope they feemed
yellow ; but when I feparated tlie inner from the external part of
them, the exterior part feen by the naked eye appeared of a perfe6t
yellow.
Fig. 31, LMN, fliews one of thefe bodies or parts which I have
beenjuftdefcribing, and of the lame fize it appeared to the naked eye
when dry and contracted. The letters M and N denote how far the
red colour extended ; from L to M was of a perfeft yellow, and
here I judged that the thread when produced from the interior part
of the animal's body was kept ready for ufe. At N is the fmall end,
the fituation of which was near the head, and indeed within the head
itfelf. Bet\\een L and O, in my judgment, is the way or paflage
tlu'ough which is conveyed tlie matter or fubftance of which the
threads are compofed. This part was of a yellow colour, and is
longer than here pi6lured, being broken ofFat O. Another part or
organ of the fame make and fliape, was alfo contained in the Silk-
worm's body, and from thefe two parts the fubftance is fupplied for
producing the two diftincl threads I have been defcribing.
Sometimes when this part or organ was broken oft" at N, I per-
ceived in it a kind of cavity, but extremely minute.
I oftentimes took hold of the end of the thread which the Silk-worm
Avas preparing to fpin, and drew it out from the body with fo much
rapidity, as by twenty- live times to exceed the fwifteft motion of tlie
worm in its own Ipinning ; and I found that when the thread was
drawn forth to the length of about fifteen or ftxteen inches, it broke
H 2
( 6o )
off, either near tlie organ from whence tlie threads proceed, (marked
\u/g. 30, with the letter C) or clfe witliin the body of the Silk-worm
itfelf. And on thefe occafions I alfo obferved that the threads were
covered with much more of the vifcous or gummy fubltance than
ullially adheres to them when fpim by th(i ^^orm, '\\hicii iubftance
alio appeared of a yellow colour.
P\u-ther, I took a Silk-worm which had fpun more of its ball or
cone tlian any I had before examined, and on opening it, I perceived
that the part which mfig. 30, had appeared of a red colour was now
quite yellow ; and wlien I opened another Silk-worm which had, as it
were, confumed or exhaufted all its filk in fpinning the web, the fame
parts appeared quite of a pale colour.
V\henl examined by the microfcope that part which is rcprefented
in fig. 31, at LMN, I difcoveredin it a great number of blood vellels,
moftly compofed of annular parts or rings. A fmall portion of one
of thefe veflels in a place where it divides into two branches, is rc-
prefented at^^. 32, FGH I K. This was not one of the largeft vellels
I faw, for near to it was one four times the fize.
1 have at feveral times when the Silk-worms had, as I fu])pofed,
)iearly finidied their web or covering, cut it open, in order to obferve
the change they underwent, and at that time I remarked, that when
the ikin about the head became loofened, the worm w as then changed
into a chryfalis or aurelia, and nothing wanting to compleat that
change, but the putting off' its (kin of a worm. But when I myfelf
endeavoured to ftrip off" this fl<.in, I found the under one fo foft and
tender, that I could not avoid injuring it.
Moreover, I have examined by the microfcope the Silk- worm,
when it firft iffiied from the egg, to difcover, if pollible, whether the
exceeding flender thread Ipun by fo minute a creature was a
double thread, and in more than one inftance, I found tiiis to be the
cafe. Thefe threads I judged to be above a thoufand times flenderer
than thofe I'pun by full grown Silk-worms, and tliey were all covered
( 61 )
with a proportionable quantity of the gkttinous or gummy matter
before-mentioned. In fliort, there is no doubt that the fame perfec-
tions exifl in a newly-hatched Silk-worm, as can be difcovered in one
full grown.
I have frequently examined the flying infecfl, moth or butterfly
produced from the aurelia or chryfalis of the Silk-worm ; and, hav-
ing before particularly defcribed the eyes of this creature while a
worm, 1 now employed myfelf to difcover the nataire of its eyes,
when changed into a moth ; and for this purpofe I placed before the
microfcope one of thofe organs of fight, which in this animal is com-
monly deemed one eye. This is protuberant or rifing above the
head, rather more than an hemifphere, and is compofed of a number
of fmaller optical organs : Thefe I counted with the greateft exa6l-
nefs I was able, beginning at the bottom of the hemifphere, and pro-
ceeding to the fummit or uppermoft part of it, which diftance made
the fourth part of a fpliere ; and in this fpace I counted thirty-fix op-
tical organs or eyes. But, not fatisfied with my own computation,
I delivered the microfcope to the limner, defiring him to count them,
and in the fame fpace he reckoned thirty-five. This latter number I
will fuppofe to be right, and from it I proceed to compute as follows :
— If tlie fourth part of the circumference or great circle furroundinga
fphere contains thirty-five, the entire circumference will contain 140.
Now Metius informs us, that having the length of the great circle in
a fphere, the calculation of the whole fuperficies of fuch fphere is befi:
andeafiefi: computed, thus: As 22 is to 7, fo is the quadrature of the
great circle to the fuperfices of the fphere, therefore in the prefent
cafe the computation is as follows ; —
As 22 7 19600 140 the circumference or length of the great
7 140 [circle.
I m . I
22)137,200(6236 5600
• 140
19600 the quadrature of the great circle. .
( 62 )
From hence it follows, that each of the fniall parts or organs of
fight of this infe6l, which is vulgarly deemed but one fmgle eye, is
compofed of more than three thoufand optical organs or eyes, but if
both parts together conllitutc a fphere, they then contain 6236 opti-
cal organs or eyes.
I have caufed this part or eye of the infe6l to be drawn of the fame
fize as it appeared to the naked eye of the limner, to give the better
idea of the wonders which are concealed in fo fmall an animal. This
is fliewn at^^'-. 33, between the letters L and M. Each of the opti-
cal organs contained in this eye is feparated from tlie reft by a line
or divifion of fix fides, or of an hexagonal figure, and all thefe hexa-
gonal organs or eyes are placed in the moft exa<5l order that can
polTible be conceived. A few of them, as feen b}^ the microfcope,
are feen at^o-. 33, a,b,c,d.
When this little part, cleared from the optic nerves within it, was
place before the microl'cope, all the furrounding objects \\ere clearly
to be feen through each of the fmall optical organs I have been de-
fcribing, though wonderfully diminutive ; for the great tower or
Iteeple of our new church in Delft, which is three hundred feet
high, and about feven hundred and fifty feet diftant from my houfe,
■when viewed through any one of thefe optical organs, ajipeared no
larger than the point of a fmall needle feen by the naked eye : and
from hence may eafily be colle6led how minute the optic nerves mull
appear to me.
Now, if we confider that a Silk-worm, witliin the fpace of eight
or nine days, Ihall not only have I'pun its web, cone, or ball, but
alfo fhall be changed into an aurelia or chryfalis, and that in the
fame fpace of time, not only its eyes but all the members pertaining
to it as a flying infect Ihall be formed, who can avoid being ftruck
with amazement at all thefe wonders fn one Silk-worm r And yet,
how little do we difcover in comparifon of thofc thiiigs which now
are and for ever will be hidden from our fight .^ tiie wliolc of which I
( ^3 )
am fully perfuaded no one will ever be able to dive into, and to ex-
plain their caufes and effe6ls.
If we examine the wings of this creature by the microfcope, we
fhall find them covered with an incredible number of feathers, of
of fuch various forms, that if an hundred or more of them were to
be feen lying together, each would appear of a different fliape. To
fliew more clearly this wonderful obje6t, I caufed eight different fea-
thers to be delineated, for 1 do not remember that I ever favv them of
fo curious a make in any other flying infe6f. Thefe feathers are
fliewn at ;%• 34, A B C D E F G H I K L M N O, and the letters A C E G
ILN, denote their quills which were fixed in the membrane or fkin
of the wing.
Although the microfcope by which thefe feathers were drawn, re-
prefented objects very diftinftly, the limner could not, through it,
iee the ftreaks or ribs in each feather, until I pointed them out to
him. Therefore I put into his hands a microfcope which magni-
fied objects almoft as much as that by which the Silk-worm's
thread was drawn, defiring him to give the figure of that feather
which tlirough it he could fee the mofl; diftiiKfUy. This is done at
fiS- 35' PQ^' ^'^ which plainly appear a great number of ftrcaks or
parts like ribs, which give ftrength to the feather, and in fome of
thefe feathers, where they fpread very wide, as at the part marked
R, I have counted as many as thirty of thefe fireaks, and if we con-
fider that every feather is nouriflied througli the quill which is pic-
tured at P, how many and how various mufl be the veflels in this
quill ?
After this, I wiped off the feathers from a part of one of the wings,
that I might difcover how clofe they were placed together, and I
found that they were about an hair's breadth afunder. And if, as
a certain writer affcrts, 640 hairs breadths are equal to one inch, we
may demonfiratively conclude, that the four wings of this inlbftare
covered with more than four hundred thoufajid feathers, for the fur--
( 64 )
face of all the wings when laid fide by fide takes up almoft three
quarters of a fquare inch ; and, as each wing is covered on both fides
with feathers, this makes the fpace of an inch and an lialf fquare. To
which if we add, that the body and legs of this butterfly are covered
with as many feathers as are on the wings, tlic number of feathers
above enumerated will be doubled.
I then examined the boney parts which give ftrength and fliffnefs
to thefe wings, and I faw more jjlainly tiiat in other flying infects
the crooked or twifted veins within them. A ver}' fmall portion of
one of thefe boney parts is fliewn at 7?^. 36, ABCDEF, within
which is feen that twifled vein, and where the bone is divided into
two parts, the vein is the fame. In the fame figure, at ABH, is re-
prefented a fmall part of the membrane or Ikin of the wing flripped
of its feathers. The dots in it indicate the cavities wherein the quills
of the feathers had been fixed.
It is alio a pleafant objedl to behold the curioufly formed claws in
each of the fliort feet of the Silk-worm, and which are Ihed or put oft'
with the fkin at the animal's change into an aurelia, one of thefe is
fliewn at /*;§•. 37, I K L, and when changed into a flying infeft or
butterfly each foot is furniflied with two nails or claws, with which
it very ftrongly clings to every thing it touches. Thefe nails or
claws are fliewn atj^o-. <j8, MNO.
To clofe this fubjedl; feeing that the Silk-worm, in its change,
only puts oflf the (kins of its feet, and that, in the fame places where,
while a worm, it had very fliort feet ; it is, when a butterfly, fur-
niflied with legs, covered with numbers of feathers, and armed witJi
nails or daws as before defcribed, the metamorphofis or change of
this creature mufi: feem almoft incredible, and cannot but excite in
ii£ the greateft admiration.
J,
On the nature of the fc ales of Fifloes, and hoiv the age of thofe Ani-
mals may be determined by obfervation of tbe fcales ; The Author's
reafonings and opinion refpeSling the Longevity of this part of the
Animal Creation.
JlT is the opinion of the Jews that they are forbidden by their law
to ufe tlie Eel as food, becaufe that Fifh is faid to be without fcales ;
and in the book of Deuteronomy , Chap. xiv. v. lo. it is written,
" whatfoever hath not fins and fcales, ye may not eat, it is unclean
unto you ;" and in Leviticus, xi. v. 12, are thefe words, (which they
apply to the lame fpecies of Fifli,) "whatfoever hath no fins nor
" fcales in the waters, that fliall be an abomination unto you.
But when I examined this kind of Fifh, by the microfcope, after
I had cleared away that vifcous or flimy matter which adheres to
them, I found tlieir (kins to be as completely covered with fcales as
thofe of any other river Fifli, which fcales (though very fmall and
thin) lie as clofe together and are placed one on another in as regu-
lar order as can be obferved in any other Fifli whatever, whetlier of
frefh or fait ^vater. Mgreover, this fpecies of Fifli is provided with
fins equally as others, namel}^ one at the head, and one above,
and another below, the tail ; and becaufe I apprehend that this difco-
very of m.ine is new, at leaf! to perfons of the Jewifli nation, (for to
this day they deem this delicate Fifh to be unclean, and hold it as an
abomination to them,) 1 determined to give a figure of one of thefe
I
A
^ ( 6G )
iValcs, (taken from the belly of the Fifh, where they are the fniaUeft,)
as it appeared through the microfcope.
Phite III. fig. 1, ABCD, exhibits this fcale ; it was taken from the
belly of a large Eel, which, next the head was of the thicknefs of
feven ting-ers or thereabouts : on the back and fides of this Fifli the
fcales are larger. The greatefl part of this fcale, ADC \\ as covered
by two others. The pait B, was placed towards the tail, and in this
pofition were all the fcales ; they were all princijiall}^ compol'ed of
a kind of globules or little balls, which globules in many places ex-
hibited an appearance, as if they were covered with a cobweb, which
by reafon of its exceflive finenefs, could not be exprefled in the draw-
ing.* In thefe fcales the globules compofing them were very tranf-
parent, though ibme more than others ; again, Ibme had in them a
dark fpot. Thefe opaque globules lying in rows contiguous to each
other, produced the appearance of divers circles or rings on the face
of the fcale. And although I did not obferve thefe fcales to be e.\-
a6lly alike, yet the circles or rings feemed to me to be of the fame
number in all of them, whence I was led to conclude, that the fcale
had been every year augmented by the addition of one circle, and
confequently, that, as there were feven circles in this fcale, this Eel
was probably feven years old. Thefe circles are marked in^. i, by
the letters EFGH IK L, and at X the fcale is reprefented of the
fame fize as it appeared to the naked eye.
Having examined the fcales on the body of a very large Eel, I
perceived that thofe on the back and belly of the Fifli were placed in
regular and even courfes behind each other, but that thofe between
the back and the belly were many of them laid obliquely, fome
towards the belly and others towards the back, but all fo dil'nofed
as to cover the fkin exactly in every part.
* This appearance feems to have been afterwards more fully iiiv^nignted by the Auihor,
and explained by a drawing, as will appear in the following pag-S.
( 67 )
* x\fter this, I examined the matter or fubftance \vith wliich thel'e
fcales are coveretl, whicli, as well as the I'cales, has been generally
deemed nothing more than flime, and is by mod perfons thought
to be an excrenientitious matter, adhering to this fpecies of Filh ;
but I am now convinced by experience, and the cleareft ocular
demonftration, that this fuppofed flime does not collect on the
animal's body from without, but is really part of the body itfelf ;
forafmuch as this fubftance, althougli it appears to tlie naked
eye, and very often through the micro fcope no otherwife than like
a cryllaliine or pellucid humour or fubftance, yet in faft it is no
other than a congeries or colIe(51:ion of veins or vedijls, which in their
exquifite fineneis or flendernefs do almoft exceed belief, fpreading
themfelves one among another in fuch an incomprehenfible and
immenfe number of branches, that I could not contemplate them
without the greateft admiration. Indeed, many were lb thin and
flender, that I could not difcover them without the moll carefid
attention, and I thought it probable that there might be others flill
more minute, fo as entirely to cfcape the fight. Such of thefe
velTels as I could diftin6lly perceive, I judged to be fo fmall
(meafurJng them by my eye) that if one of the globules-f- of blood
from whence its rednefs proceeds, were to be divided into a thou-
iand parts, not one of thofe parts could pals through thefe wonder-
fully thin and flender vefiels.
From thefe obfervations I concluded, that this fubftance only
anfwers the purpofe of a membrane or fkin lying next to the fcales,
and that, when an Eel is creeping through a narrow pafl'age or hole,
* Thefe obfervations of the Author on the Eel appear to have been written poflerior to
the time when he publifhed the preceding ones, and it fliould feem, that what he before
defer ibcs to be an appearance like a cobweb adhering to the fcales, is the efFedt of the vefiels
here defcribed.
-j- The author's computation of th? fize of a g! ibule of blood, will be found in another place,
where he treats of that fubjedt.
I 3
( 68 )
a part of this jncmbranc or cuticle, which we call flime, is rubbed
off in the paHage ; and that wiien Eels are kept in any kind of veflcl
without water, and in their motion wear off this cuticle, they can-
not long furvive ; and upon my talking over this lub)c6l with a
Fifli-nionger, who was a very intelligent man in his bufinefs, he con-
firmed all that I have here mentioned.
Further, I imagined that this cuticle or Ikin io covering the fcales
of Eels, and in Tome fort proceeding from the fcales themfelves,
and the veflels which in a great meafure compofe that fkin which
we imagine to be flime, extend fo far and vv'ide, that the vedels pro-
ceeding from one fcale fpread over more than twejity-iive others,
and that this is the reafon w hy this flimy matter covering the fcales
is fo thick and tough.
But, not yet fatisfied with thefe obfervations, I endeavoured to
find out the veflels in the fcales from whence thefe Aim}' excremen-
titious veflels were formed, and in order to exhibit more plainly the
rousfh or wrinkled make of the fcales, I have caufed an exceedino;
fmall particle of one to be delineated, the appearance of which, by
the microfcope, was that of a lucid or bright cryflal, both v^ithin and
without. This is fliewn in jig. i, I K L M, wherin the fide I M, re-
j)refents that part which was fixed or rooted in the Fiih, being about
the length of two common grains of fand. I have fometimes divi-
ded the Icales of this Fifli into fmall parts, and I always found that
though the wrinkles in them appeared very pellucid, they were com-
))ofed of nothing but thofe inconceivably flender flreaks, or rather
' veflels, mixed and twiflied one within another, as is in fome fort re-
prefented in this figure by the letters K LN.
Some years after the preceding obfervations were publiflied, I
received from a perfon of fome note in this city, a parcel of fcales
taken from a very large Carp which had been kept in his Filh-pond,
and was 'io tame that it would take food out of a pcrfon's hand.
( 69 )
But in the time of a fevere froft, the gardener being employed in
breaking the ice with an liatchet, to give frelh air to the Fifli in the
pond, this Carp came to the hole, and unfortunately received a
wound from the hatchet, wliich occafioned its death. This Fifli was
in length 42I- inclies, and in circumference at the thickeft part of its
body 33:f inches.
In order more eafily to cut one of thefe fcales in pieces, I fteeped
it in warm water, and then I cut off a flice from it, palilng througli
that part where the lirfl; formation of the fcale appeared, which origi-
nal foale was very minute, and I then obferved forty ro\\s of fcales
lying one on another, or in other words, this fmgle fcale was a chif-
ter of forty other fcales lying one on another. For every year a new
fcale fomewhat larger than that immediately preceding it, is added
to the number, and is as it were glued to the former ones ; therefore
as many of thefe fcales as are found tiius joined together, fo many
are the years of the Filh's age. This alTertion of mine is however
violently contradi6ted, becaufe many people think that 1 cannot by
any means prove what I affirm.
I determined therefore, to cut oif a flice from this fcale very ob-
liquely, whereby the rows of the component fcales might be more
clearly difcerned, and I caufed a drawing of this to be made from
the microfcope, which is fhewn ^tjig. 3, A B C D ; the part reaching
from A to B, or from D to C denotes the difference in fize by which
each newly-formed fcale exceeds that of tlie preceding year, the
whole thicknefs of the fcale as it appeared through the microfcope,
is the fpace between B and C, but in fa6l, the real thicknefs, as feen
by the naked eye, is no more than that of an hog's brifile.
Another piece of the fame fcale, cut flill more obliquely, I placed
before another microfcope, a drawing of which is given at fig. 4,
E F G H. The fpace between E and F is the thicknefs of the fcale,
and as many divifions or rows as are there pictured, fo many of the
( 70 )
Iniall component fcalcs lie heaped one on another, (at leafl as far as
tlie limner was able to obferve them) and fo many years had elap-
Icd between the formation of the firft Icale, and all tlie others which
were added to it.
This cutting or dicing off pieces from the fcales, does not fuccecd
equally well in all, for ibmetimes their thinnefs caufes it to fail, but
if the extremity of each fcale can but be perceived, tlie age of the
Filh may be gathered from it with little danger of millake. In order
to fhcw this irregular kind of fe6lion, I caufed a fniall piece of that
defcription to be drawn from the microfcope, and tliis is Ihewn in
fg. 5, I K L M ; here the additional fcales produced every year,
fometimes appear of a darker Ihade than thcv arc in reality, and
therefore the yearly increafe in fize feems reprefented at I O and
M O, but the addition of three years' growth appears at I O K. At
fig. 6, between P and O, is fliewn the natural fize of the flice or
piece of fcale reprefented when magnified, ^tfg- 4.
Since we now find, that the fcales of Fifhes are every year aug-
mented in the way I have been defcribing, we may form a pretty
good judgment as to the time when tliis augmentation is made by-
analogy to what we obferve in the other productions of nature, and
thence we fliall conclude that the additional fcalcs are comi)lcatcd at
that feafon, when the further growth ceafes. For this is evident in
trees, at lead fuch as grow in theie regions. The like alfo is the
cafe in regard to cows, for between certain fpaces of time, when
their growth is intermitted or ceafes and when it again returns, it is
fhewn in the horns, whence we gather that as many knots or rings
as are found on the cow's horn, fo many years of age is the animal.
And, though this may not appear exa6tly in the fame manner in
all creatures, yet we muft allow, that fuch a diflinguifliing circum-
Itance exifls, and this is proved in the falling ofl^'of tlie iiair from ani-
mals, and the fhedding of feathers by birds, at certain regular periods.
( yr )
I have often confidered with myfelf, refpedling the longevity of
Fiflies, and I am perfuaded that in deep and extenfive waters, and in
running dreams, where the water does not corrupt or putrefy,
they are not hable to any difeafes, nor ever die of old age. Such
wounds as a Fifh may receive, either by fwallowing the hook baited
to catch it, and which, being broken off and remaining in the
fiomach, may caufe an exulceration ; or by devouring fome iubftance
which it cannot digeft, are not to be deemed difeal'es, but accidents.
Now, terreftrial animals, through great fatigue, heat, cold, hunger
or thirii, may eafily fall into diftempers and die, but to thofe acci-
dents Fiflies are feklom or never fubjeft,
Fird, as to fatigue, this in Fiflies cannot be great, becaufe their
chief exercife confifls in the lai'ger purfuing the fmaller, in quell of
them for food ; or in the flight of the fmaller ones from the larger ;
and in tJiefe exertions the fine juices of their blood can in no degree,
or at lead but very little, be exhaufted ; becaufe in fuch kind of pur-
fuit or flight, no evaporation can be produced from their bodies
througli heat or drynefs; befides, they never want for drink, by
which means their blood, and the other juices of their bodies are
kept continually diluted, fo that the circulation is conflantly pre-
ferved.
No one can pretend to fay that a Fifli is ever killed by heat, for
many kinds of fifli, in the middle of fummer, and in the burning heat
of the fun, do either play, as it were, on the furface of the water ;
or hide themfelves under the leaves, weeds, or otlier fubflances at
the bottom.
As to cold, we do not know that Fifli in deep waters ever perifli
with cold ; but we know by ex*perience, that at fuch feafons they
feek the bottom of the water.
As to food, they are not eafily killed by hunger ; many Fiflies live
for five or fix months fpace without any other fupport than what they
( 72 )
receive from the water, or rather from the fmall particles in it, whicli
are by us commonly confiderecl as part of the water only ; in fuch a
fituation indeed, they increafe little or nothing in fize, but rather, if
they were before fat and plump, they will fall away.
I amalfo perfiiadcd, that all Filhcs which have a conftant fupply
of food, do daily increafe in lize, and this without ever ceafing to
o-row, fo that any real definite fize cannot be afllgned to them, as
it can to terrellrial animals, fome of which arrive fooner, and others
later, to their full and perfe6l flature, which they never afterwards
exceed, altliough they continue to hve many years. The reafon of
which, I am convinced is this, that terreftrial animals continue grow-
ing as long as their nutritive juices have force fufficient to protrude or
thrult thenifelves through the cavities of the bones, and fo to increafe
the fize of them, as well in length as in thicknefs. But when the
bones of thefe animals, by being expofcd to the air, are become fo
rigid and hard, that they cannot be any more difcended, their far-
ther growth mufl necefi'arily ceafe, and any frefli fupplies of nutri-
tive juices can only tend to increafe the animal's fatnefs. But the
bones of Fiflies are for the moll part dellitute of marrow, and they
cannot be rendered rigid by expofure to the air, confequently the
very fmall tubuli or pipes of which they are compofed, are exceed-
ingly foft in comparifon with thofe of other animals. All which con-
lidered, there leems no reafon to exift, why the bones of Fiflies
fliould not continue always growing, i'o long as the animals do not
want for food.
In the lakes with us, where are many Fiflieries, Pike have been
caught of the lengtli of 56 inches, and 36 or 38 pounds weight.
Pearch alfo 28 inches long ; and who can tell to what fize thefe
Fidies might have arrived, if they could have longer efcaped the
nets ?
The Author's refutation of the dodlrine of equivocal or fpontaneous ge^
neration in the inflance of the Sea-Mufde, zvith a particular defcrip-
tion of that f pedes of Fifh.
1 HAVE been informed, that a book is publiflied at Rome, by a
learned Jefuit, named Philippo Bonanni, wherein he maintains, that
animalcules, or imall living creatures, can be produced out of in-
animate fubftances, fuch as mud or fand, by fpontaneous generation,
according to the doctrine of Ariftotle ; and it feems that this learned
gentleman is himfelf very defirous to fee my obfervations on thefub-
jecl. I fliall therefore proceed to confider Signor Bonanni's pofitions,
and I doubt not, that upon inveftigation, they will be found of no
weight or fubftance, but will vanifli like fmoke or vapour.
We will admit, that out of the mud or fand which is found on the
fea-fhore, or the beds of our rivers, at low water, Ihell-fifli or tef-
taceous animals come forth ; but it does not from thence by any
means follow, that they are produced without any regular courfe of
generation.
Among the mud, in the creeks or fliallows of our fea coafts, are
taken great quantities of that fliell-fini, called Mufcles, which are
uled by us as an article of food ; and, as I had in the autumn been
employing myfelf in obfervations upon this fpecies of fifli, I applied
to a filherman who made it his bufmefs to catch Mulbles, and quef-
tioned him as to what his opinion was, with regard to the propaga-
tion of that fiih.
K
C 7-h )
This fifhcnnaii, ulio was a very intelligent man, aucl of good
efliniation in his profefllon, and had been brought up to it from his
youth, informed me, that he had often experienced, that in the fame
tradl of coaft where he had found for feveral years fucccflively very
good Mufcles, and in great abundance, yet afterwards in or about the
fame ])lace, very few or none ^^•erc to be got ; for which he afllgned
thefe reafons :
" At the time of the Mufcles laying their eggs or fpawn, which
lads but for a Ihort feafon, this fpawn, by ftrong tides and heavy gales
of wind, will be carried from the places where it is depofited, and
when the water becomics (till and calm, it will fink to the bottom, or
adhere to the weeds growing there ; and then in the fpace of two or
three years, a good and plenteous Mufclc-bank will be formed in the
place; adding, that by this means Mufcles are taken where noncwere
ever found before, and Mufcle-banks formed of very great extent,
tlie fpawn laid by the Mufcles being in fuch abundance, as to make
the fea-water appear of a white colour."
If then, at the feafon when the Mufcles depofit their eggs or
fpawn, we take up a quantity of the mud or fandy matter from the
Ihore, and keep it covered with water, we need not wonder if we
find Mufcles or other fliell-fiih produced from thence ; but if we
imagine that this comes to pafs by any other means than the ordi-
nary courfe of generation, we Ihall therein deceive ourfelves. And
for my part, I hold it equally impoOible for a Imall fliell-fifh to be
produced without generation, as for a whale to have its origin from
the mud.
The eggs or fpawii of Mufcles, and other fliell-fifli, being earned
along with the fea-water to the fides of Ihips lying in harbours, will
adhere to them, and become fliell-fifli, by which means thofe ihips in
their voyages to other countries, will introduce luch kinds of Ihell-
hlh as were before unknown in thofe parts.
But how can it be conceived that living creatures can proceed from
( 75 )
fand, or obtain any nourifliment from thence ? for there is no other
difference between the grains of fand, and t]ie beach-ftones on the
fea-fliorc, than that the one are larger than the others ; and, as in-
capable as glafs is of affording fupport to any Uving creature, fo is it
impoffible for any nourifliment to be found in fand.
If it were pofilble for the mere fand on the fliore to produce fhell-
fifli, how much would our coaRs abound with them, and not with
them only, but alfo with all other forts of filh ; for tlie flat-fiih feed
on tliefe fmall fliell-fifh, and thereby become very fat and good ; and
fo does alfo the whiting.
The chief reafon, in my opinion, wliy we do not find fliell-fifli in
equal plenty, at all times, is, that the ftrong nortli-weft winds blow-
ing diredlly on our coall, do fo ftir up the fand and muddy bottom on
the fliore, that the fliell-fifh are tliereby overwhelmed and buried,
and fo perilb.
During the laft hve or fix years, we have not had any great ftorms
from that quarter, and we have for thel'e laft tlirce or four years fuc-
ceffively, had fuch excellent fiat-fifli, efpecially flounders, that no
one remembers to have feen the like ; the reafon for which I have
already afiigned, namely, tliat the ihell-fifh during that fpace of time,
multiplied exceedingly, affording plenty of food for fattening the flat-
fiibes. And this is alfo proved by experience ; for whenever flounders
are in perfection, their ftomachs and bowels are found to be full of
fragments of fmall fliells. And, upon reflecting witli mj^felf as to
the caufe of thefe fmall fhells being fo broken into fragments, I could
not aflign any other reafon than the following :
The flounder, fole, turbot, and otlier flat-fifli, are formed by na-
ture with their mouths diftorted and in a different pofition from that
of moft other fiihes ; and this formation feems to be, for enabli!:ig
thcm to pick up their food from the bottom of the fea, and not to go
K 3
( 76 )
in chafe of otlier fifli ; and I conceive that tliefe flat~fi(h, when pick-
ing up the fniall fliell-filh, do break tlieir fliells to pieces in their
jnoulhs (which I'ccm to me to be formed principally for that purpofc)
and then Iwallow tliem, rejecting thofe Ihells which are too hard for
tbem to break, for which reafon we never find any very hard or
large pieces of ihells in their Aomachs ; and it is not in the power of
tlie flat fiili to feparatc thefe Imailer ones from their Ibclls, bccaufe
they are all, as far as I have ever obferved, clofely united to them by
ligaments or tendons, and always keep their fliells clofely fhut.
I have enquired of thofe Filhermen, whom I thought men of re-
fle61:ion, what could be the reafon why fome years ago cur flounders
were very indifferent, and for ihel'c laft three or four years fo exceed-
ing good ; for which they could not affign to me any reafon ; but
when I laid before them my fentiments refpecling thefe fiili being
fattened by feeding on the fmall fliell-fiHi, they were furprifed there-
at, and added, that this might very probably be the cafe. But upon
converfmg with two principal merchants who fend out filliing-vefilbls,
they not only agreed with me in my opinion, as before related, but
alfo in the following, namely, that not only the flat-fifh feed fo much
on the fmall fhell-fifli, but the whiting is fo abundantly nourifljed by
them, that in the fummer-time its fleO:i becomes hard and tough ; for
this reafon, at the time when the fliell-fifli abound on our fliores, the
whiting reforts thither in quell of them, and this latter is followed by
.the cod-fiHi, which preys on the whiting. In fliort, I conclude that
the plenty of fifli found on our coaft, proceeds from this caufeonly,
the great quantities of fliell-fiili which every year breed there.
Towards the end of the month of February, being the firft time in
the fpring that Mufcles were brought to our city for fale, I caufed
fome of them to be bought, in order to make my obfervations there-
on : I found thefe to be very lean, and for a loiig time my fearch
after their fpawn was fruitlefs, though I could not think that the
time was pad for their depofiting it.
( 77 )
Upon examining that part of the Mufcle which is called the beard,
I not only found it of a wonderful make, but the motion I law in the
fmall component parts of it was fo incredibly great, that I could not
be fatisfied with the fpedtacle ; and it is not in the mind of man to
conceive all the motions which L beheld within the compafs of a grain
of fand.
When I obferved the large and ftrong tendons or hnews in the
Mufcle, which are fixed to the fhell, and thofe which lie in the fame
order and pofition as the ribs in a terreflrial animal, I thought that
we cannot fufficiently admire the wonderful make of this fi(h ; and
that if we could obtain an infight into all thoie parts which we fee
in one of them, and could we aflign their feveral ufes, and give them
names, and alfo make drawings of them, I doubt not that we fhould
admire fo elaborate and curious a work, beyond many others of
nature's produ6tions ; and that thofe perfons who now afl'ert tliat
fliell-filhes (among wliich the Mufcle is in leaft eflimation) arc pro-
duced fpontaneoufly, or of thcmfelves, would renounce their opi-
nions, and embrace the truth, namely, that fo perfe<5l a creature can-
not be produced from corruption, cojigealed water, or mud, but can
©nly be generated by parents of its own fpecies.
I obferved that every Mufcle was provided with a kind of firing
or ligament, which, at a little diflance from the fifli, was divided
into 8, ID, 12, 15, and even 20 other hgaments of different lengths ;
and with thefe ligaments, I obferved, that the Mufcles faftened thcm-
felves to other Mufcles, and alio to pieces of Udells, and to fliell-filli
of other fpecies.
I was defirous to know how this faftening was efFedled, and
which I immediately difcovered ; for I favv, to my great furprife,
that the extremity of every ligament was provided with a thin flat
mciTrbrane or fkin, of a roundiili fhape, which was as firmly fixed to^
( 73 )
^the fliell on wliich it was placed (the ligament being in the middle of
it,) as if it were glued to the fliell ; and when I endeavoured to pull
off tlie ligament, I found, by feveral trials, that (though it was very
itrong and tough, in proportion to its fize) it would break before the
flat tliin membrane could be loofencd.
Hereupon I recolledled, that wlien a boy, I had often amufed my-
felf with a play-thing which we called* " een Treck-lcertje." This
js afmall round piece of leather, about two inches in diameter, hav-
ing a fmall hole in the middle, through which was drawn a pack-
thread, with a knot at the end. This leather being firfi: foaked in
water, was placed flat on a ftone, and with this we could not only
lift up the ftone, but carry it to fome diflance.
Now, upon the fame principle as the ftone adheres to the leather,
partly by the prelHire of the atmofphere, and partly becaufe no air
or water can gain admittance between the ftone and the leather,
thelikeeffe61: is produced in the coheiion or ftickb^ig of the membrane
I have been defcribins:.
I have thought it proper to give a drawing of the ligament before-
mentioned, and its feveral branches : and in Plate III. j6^. 8, is flaewn
a part of it, which is cut off at A in the part which comes out of the
ftiell ; this in /^. 7, is fhewn at BE of its natural ftze. Iny?^^'-, 8,
F G H I K are feen the ramifications or branches, or rather a fmall part
of them ; and at L M is fliewn one of the fhort liganients, with its
membrane NOP, the ligament here appears on the upper fide of the
membrane, in like manner as if the latter was fixed to fome other
ihell ; and here are to be feen the many parts whereby the ligament
is joined to the membrane, which latter alfo appears fomewhat ele-
vated at the place of joining,
*That is, in Englifh,a pulling or drawing-leather ; it is a common play-thing among boys
.inJinglandj.and is called by thcra a fucker.
( 79 )
At Q R is r^prefenled another ligament, and at S T V its mem-
brane, with the concave part of it, appearing open, being in a con-
trary poiition to tlie former reprefentation. I have often feen this
cavity reach into the ligament as far as M or R, but otherwife it is
quite clofe and compact.
Each of thefc I'gaments confifls of a great number of exceflively
fmall particles, wnich cannot be contemplated without the greatefl
admiration, efpecially when we recolle6t the power v/hich the Muf-
cle has of moving each of thefe ligaments, and alfo that the mem-
brane muft be placed quite fmooth and flat upon the fhell, to whicli
it is fixed, in order to caufe it firmly to adhere thereto.
Now, if we farther confider that Mufcles, while in the fea, always
lie with that fliell upwards which they open occafionally, and that
their fliells (which are very thin) and their bodies together are but.
little heavier than the water wherein they live, and alio that many
of them at low ebb-tides are left deftitute of water, at which times,
in my opinion, much air muft inlinuate itfelf between their fliells, by
which means they become lighter than the water; they would then.:
be liable either with the ebb to be carried out into the deep, or by
the flood to be thrown upon tlie land, and fo w^ould perifli. But
provident Nature has taken care to preferve them in this refpe6l,
by furni filing them with a ligament, fpreading into various branches,
and at the end of each branch aji organ, which I have named a mem-
brane, by the help of which the Mufcles can fix themfelves either
to empty fliells, or other fubftances, or to one another, by wliiclv.
means they are preferved.
But as my princii)al defign was to difcover, as far as poflible, the'
generation, or procreation, of thefe fifli, I come now to that part of
tiie I'ubjeft.
I obferved, that thefe Mufcles, fome in a greater, and others in a
lefs degree, had the outfides of their fliells covered with a kind of
fubftauce, thinly fpread upon the fliell, and firmly adhering to it, or
( So )
rather to the membrane which covered it. Obferving this by the mi-
crofcope, I faw that the particles of which it confiftcd, were all of a
iimilar form, and alfo placed fide by fide, in regular order, and tlie
jnembranes or fkins of thefe particles, as it were, united, or clofely
joined together. I feparated a part of this fubftance from the Ihell
iind placing it before the microfcope, I found that all the regularly
difpofed particles were much longer than they were broad, alfo that
one of their edges was roundifh and thick, the other terminating in
a point or edge, and moreover that in many of them one fide was
rifing, and the other flat ; in a word, many of thefe particles, in
fliape, were vejy like a Mufcle ; and I not only thought that they
were the eggs or fpawn of tlie Mufcle, but I alfo obferved, that when
I broke the flrong membranes inclofing them, feveral of the eggs,
which were in iLape like a Mul'cle, appeared lying fingly and feparte-
ly on the outfide of that membrane ; and when I feparated thefe un-
formed Mufcles fingly, one from another, I imagined that I could
fee the membranes or tendons of which they were compofed.
I alfo faw the fliells, membranes, or coverings of feveral eggs
which were empty, and which I faw, or more properly fpeaking,
imagined to be barren eggs. In other parts of this fub fiance I faw
eggs wherein I concluded that there were unformed Mulcles, which
conclufion I gathered from the multitude of vefl'els which I faw,
which veflels conftituted the (hape or figure of a Mufcle.
Thefe eggs were not larger than a grain of common fcowering-
fand.
Moreover, I obferved, that the fmall or taper ends of the fl:ells
were feldom or never covered with the fpawn or eggs, the real'on of
which I took to be, that at the time the Mufcles emit their Ipawn,
they lie with the flat and broad part, as fliewn at Jig. 7, A B C D,
iippermofi, and that part marked with the letter A, next the ground,
£>r bottom ; for I have often obferved that when Mufcles have
( 8i )
been cleaned and put into a vedel of water, and an handful of fait
thrown upon them, many will be foon found placed in the pofition
I have mentioned ; and while they lie in this pofition, and the eggs
are put fortii from the part marked C D, there muft necefTarily be
more eggs lodged near that fpot, than towards the farther end of the
lliell.
Several of thefe Mufcles I placed in my fludy, in two glafTes of
water, with fome fait fprinkled on them, in order to examine them
daily, and fee the progrels of growth in the young ones ; and upon
this occafion, I could not fufficiently admire the exaft and regular
order in which the eggs were in many places difpofed, jufl: as if they
had been fo placed by men's hands ; and from hence I was convinced
that Mufcles do not, like many other fiflies, lay their eggs promif-
cuoufly, but that they mufi: be furnilbed with fome kind of organ,
which they can projefl beyond the ihell, and with it difpofe them fo
regularly.
I have before faid, that I thought I faw a kind of finews or tendons
in the eggs ; and upon further examination, I perceived fixteen of
thefe tendons, like flreaks, in the unformed Mufcle, and among
them I faw fome ftill fmaller ftreaks, from whence I concluded, that
they were in fa61:, vefTels to form the fubftance of the future fhell, for
they lay all in one diredlion, that is, from the fmall end, fpreading
or diverging round about ; and they were thickell at that part, and
thinneft at the extremities, fpreading wider towards the broad and
thin end of the fliell : I caufed a drawing to be made of a few of the
eggs, in the order they lay on tlie parent lliell, and as they appeared
through the microfcope ; this is fliewn at fg. 9, ABCDE, reprefent-
ing eight of them, in lome of which it may be feen tliat one fide is
more curved than the other, and in which eggs may alfo be feen the
finews, vefiels, or flreaks I have mentioned.
Upon confidering that tiie lobftcr and tlie fhrimp carry their eggs
L
( 82 )
about them until the young are perfeilly formed, it feems probable
to me, that this is alfo the cafe with the Mufcle, for othervvife, how
could this fpecies of fifli be propagated ? efpecially if we confider that
they lay their eggs in the middle of winter, and are generally in
fhallow waters, where the fliore is muddy ; and if tlie eggs were not
depofited on the Ihells, they would be buried in the mud, witli the
common flux and reflux of the tide : not to mention that in llormy
weatlier they would be carried out to fea ; but while they are fixed
to the fliells of the parent, and thefe laft adhering to folid fubllances
on the fliore, the eggs are, by this means, in great numbers, pre-
ferved ; and thefe young Mufcles, when come to fuch maturity as
to be Separated from the fliells, may, in windy weather, flrong tides
or currents, be eafily carried to other muddy fliores on the coall, in
places where for many years before no Mufcles were to be found.
I have made a rough calculation of the numbers of thefe eggs, and
I compute that there are frequently more than two thoufand flxed to
the fliell of one Mufcle ; in fa6l, I have feen Mufcles, each of which
I judged had more than three thoufand on it.
I have before faid, that the eggs of Mufcles are the fize of com-
mon fcowering-fand, but as this is not of the fame fize in all coun-
tries, I compute that, to the beft of my judgment, feven of thefe
ego's, in breadth, are equal to the fifteenth part of an inch, confe-
quently the breadth of 105 eggs, is equal to one inch ; and I alfo
compute, that fixty eggs, in length, make an inch ; therefore a
fquare inch will contain 6300 ; and as each egg is no thicker than
broad, 105 of them mufl: he one on another to make the thicknefs of
an inch ; the fum total then of the eggs which will be contained with-
in the fpace of a cubic inch, is 661,500 ; and hundreds of fuch eggs
may lie under fliells, fand, or mud, without being perceived, and yet
Mufcles be produced from them.
Having taken fome of the unformed Mufcles out of the eggs, I
( 83 )
caufed a drawing to be made of their figure, as near as the Engraver
was able to imitate it ; this is {hewn at fig. lo, F G, which repre-
sents fuch an unformed JMufcIe, inclol'ed in its membrane, or cover-
ing, in which the flreaks before-mentioned, did not appear, until the
greateft part of the moiRure thereof, was evaporated. Fig. ir,
HI K, fliews another of them, tiie ftreaks, or veflels in which, be-
tween I and K, ap])eared feparated, or fundered from each other ;
and this was done in the taking it out of tlie ^gg, being in that ope-
ration deprived of the furrounding membrane, or fkin.
At the latter end of April, when I had iiniflied the preceding
obfervations, I received a large jar full of Mufcles out of Zealand;
upon examination of which, I was much furpriled to fee that moll
of the Ihells were quite fmooth and poliflied, being not only deftitute
of eggs, but for the molt part, bare of the membrane, w hich gives
them a blackifli colour, ib that they now appeared of a lively blue ;
however, I found four or five with perfc61: eggs on them, and in them
were young Mufcles ; fome of thefe ! took out of the eggs, and now
plainly faw, that what I had at firft taken for the unformed Mufclc,
was, in fadl, only the ligament, or flriiig, whreby the young Mufcle
was nourllied. A drawing of the real Ihape, as it now appeared to
me, is given at y^^. I 2, where GH I repreients the ligaments of the
unformed young Mufcle, and I K the Mufcle itfelf ; another of them
is reprefented at Jig. 13, where LM ihews the firings or ligaments,
and MN the Muicle ; and this lafl figure, I think, exhibits the true
form of the young Mufcle, as it lies in the egg ; and from thefe lafl
obfervations it appears, that the parts reprefented in Jig. 10, at G,
and in^^. 11, at H, were only the fubflance, or matter, from whence
the Muicle would be formed, and which, at the time when that draw-
ing was made, had not come to fufficient perfeftion to render the
parts dillinguifliable.
Now, fmce we fee, that the eggs of Mufcles adhere fo long to tiie
" L2
( 8^ )
fhells of the parent, before they are perfectly formed, and alfo confi-
der that during all that time the}' miift be fiipplied with nouriiliment,
we fliall not wonder that the parent Mufcles, during that time, do
become lean, efpecially in the month of April, for then the young are
mofl in need of fuftenance.
We may alfo here obferve, that in our enquiries after any truth,
and more efpecially in regard to the generation of fmall living crea-
tures, which cannot be examined by the naked eye, we ought not to
rely on any tales that are told on thefe fubje6ls, but on our own ex-
perience, and even that not liglitly, but by long and unwearied
trials and experiments, whereby to come at the truth.
In the courfe of the laft obfervations, I examined that hard aixl
variegated, or marbly- coloured part, lying in the middle of the
Mufcle, which fome call the heart, and others take to be the tongue
of this fifli ; and when, upon the Mufcle, I cut out this part, and
placed it before the microfcope, I obferved fo tremulous or quiver-
ing a motion in the furface, as if millions of little living creatures
were running about upon it; befides another motion, which the part
had to and fro. This part the Mufcle can extend fo far, that I think
it will almofl reach all over the fliell, which made me think that,
perhaps, by this organ, the eggs are placed on the fliellinthe regular
order I have before defcribed.
*
Of the Mufcle zvbicb is found infrefJj zvater ; a particular defer iption of
its internal formation, and of the manner in which its young are
produced.
HAVE obferved, tliat when our navigable canals here in Holland,
or our ditches are cleaned, a kind of large fidi are taken from the
bottom, named by us, " * Veen Moflelen," or Peat Mufcles. Of
thefe I procured fome, which were about three or four inches long
with very thin fliells.
A countryman, whom I faw colle6ling thefe fliell fifli, told me
they were to be found under the banks, and in the fliallow parts of
the ditches, or canals, among the leaves and twigs, or other litter ;
and, indeed, I have feen them taken in thofe places ; but as I was
certain that thefe fhallow places were frozen to the bottom in the
winter, which the fliell fifli could not furvive, I was told that they
had a power of moving from place to place.
To fatisfy myfelf, in this refpedl, I made two experiments on
thefe Mufcles, of which I put fix or eight into an earthen veflcJ,
with a flat bottoin, and poured on them ibme of the fame water in
which they were taken ; this veFel I placed in my ftudy, and I found
that in a few hours time, they had all changed their pofitions, and
had approached nearer together, than they were when firft placed in
the veflel.
* This word, " Veen, " means the Turf or Peat, which is dug up in great quantities in
Holland, and is their principal article of fuel. Our author has a very ingenious diircrtation
on the origin of this fubftance, a tranflation of which will be found in its place. — Thefe frefli
water Mufcles are found in the rivers in England.
( 8(? )
And 1 obferved, that thele Mufcles, about the luiddle of their
ihells, thruft out, through the opening, a flelhy fubflance, or organ,
about t\vo-thh-d parts the length of the flicll ; this part was about
half an inch broad, and fliarp at the end ; and in order to move
tliemfelves from phice to place, they thruft tiiis organ luider their
Ihell, and applying it with a quick motion to the bottom of the place
where they lay, could by this means not only change their pollure,
but turn thcmfelves upfide down.
At the end of the month of Auguft, upon opening fix of thefe
Mulcles, I found many eggs within them, which were fo perfect,
that I could diftinguifli the newly formed fiiells, fo that they were
not lb properly to be nan^ied eggs as unborn Feat-Mufcles. Two of
the parent Mufcles were fo f mall, that I judged they were not above
a year old, whereas the others v.ere, in my opinion, fix, eight, or
nine 3'ears old ; but the young Mulcles were of the fame fize in all
of them.
In the beginning of September, I procured about fifty more of
thefe Mufcles, and upon opening twelve of tlicm, I found two where-
in the young ones feemed to be fo perfe6l, that they would proba-
bly loon be excluded from the parent. I always found that the eggs
were firft formed in the flelhy part of the Mufcle, but as they ad-
vanced in growth, they were moved to that part which, in oyfters,
is called the beard, and which, by the great number of the young
Mulcles contained therein, then fwells in bulk.
As there are many perfons who are unacquainted with this fpecies
£)f Mufcle, and others who may wifli to invcltigate the particulars of
my obfervations, I have caufed the foUowinir drawinjrs to be made :
Fig. 14. G H 1 K L, Ihcws one of thefe IVefli-water, or, as I call
them, Peat-Muicles, of the ordinary fize, which is opened fo as to
leave die whole of the fifli lying in one of the fliells ; at H I K, is re-
prefented the empty Ihell, and at M M, the two tendons, or finews,
by the help of which the filh fliuts and opens the Ihell ; and here it
( 87 )
is'to be noted, that thefe fifhes, by reafon of the leno-th of their
fliells, are each provided with two of thofe tendons, or finews, where-
as oyl^ers and^ fait- water Mufcles have only one. N O P is a thin
membrane, or fkin, lying folded up, with which the whole infide of
the empty fliell had been covered, or lined.
O R S is one of the two receptacles wjierein the eggs, as they ad-
vance to maturity, are lodged, and which parts do then become fwol-
len thereby, but at other times they are very thin ; thefe parts, in oy-
Hers, are called the beard; T V is the other oftheie receptacles,
which, in oyfters, is alfo called the beard ; and in thefe receptacles,
I did not obferve any thing particularly remarkable, except their
wonderful make.
W X Y is a iblid flelliy part, wrinkled on the outer edge, and in
rerp36l of the other parts of the fi(h, very ftrong ; this part, as I
have already mentioned, the Mufcle protrudes, or thrufts out of its
fhell, to a conridera))le length, when it prepares to change its place;
and when at reft, it generally has a fmall portion projecting out of
tiie fhell ; but if it be touched, though very lightly it inanediately
withdraws it. The fpot marked with the letter Y, is the place where
the eggs lie before they are depofitcd in what we call the beard ; and
if an incifion be made in this part, the eggs, with a watery liquor,
iOue forth.
Some of thefe Mufcles I o])ened in the prefence of the Engraver,
in order, that as foon as I had taken fome of the young ones out of
their receptacles, he might make a drawing of them, for, were they
fuffbreJ to ftand but a, few hours, their true figure would be loft.
The unborn Mufcles being put into a glafs tube, and placed before
the microfcope, I faw with afloniHiment a molt pleating fpedacle,
for every one of them, each in its particular membrane, or covering
had a flow circumvolution, and that not for a {hort fpace of time,
but fuch turning round or rotatory motion was obfervable for three
hours afterwards, and it was the more curious, becaufe the young
Mufcles, during the whole of their motion, conftaiitly kept in the
( 88 )
centre of their membranes, juft as if one were to fee a fpliere or
globe revolving upon its axis. This uncommonly pleafingfpedlacle
^\as enjoycci by myfelf, my daughter, and the Engraver for three
wliole hours, and we thought it one of the moH delightful that could
be exhibited.
Fig, 15. A B C D E exhibits fix of thefe unborn Miifcles inclofed
in their refpective membranes ; they were drawn by the Engraver in
the moft accurate manner he could, while they were in motion. Of
thefe, I computed that each parent Mufcle contained fome thoufands.
I had at the fame time fome unborn Oyflers before a microfcope
which I had taken out of the parent Oyfter five weeks before, and
as they ftill appeared perfetSf in fliape, I caufed a drawing to be made
of them alfo, and this is lliewn at fig. 16, F G H I. \n fome of
thefe the openings of their fhells were plainly to be dilcerncd.
Thefe young Oyfters bore the mofi; exad: refemblance to full
grown ones, though they were fo minute that one hundred of them
laid together would not equal an inch in length, and I have computed
that each parent Oyfter contained three or four tiioufand of them.
t
-If-
On the Circulatioti of the Blood ; that it is not difcoverahle by the fight,
in an human body, nor in the bodies of terrejlrial animals : the fame
completely feen inffl^es, and the nature of it particularly defcribed.
JL HE Blood is compofed of exceeding fmall particles, named,
globules, # which, in moft animals, are of a red -f- colour, I'wimming
in a liquor, called, by phyficians, the ferum ; and by means of thefe
globules the motion of the Blood becomes vifible, which otherwife
would not be difcoverahle by the fight. Thefe particles, or globules,
are fo minute, that one hundred of them, placed fide by fide, would
not equal the diameter of a common grain of fand ; confequently, a
grain of fand is above a million times the fize of one fuch globule.
I have often endeavoured to view the circulation of the blood in
terreftrial animals, but without fuccefs, by reafon that no parts of
their bodies were fuflficiently tranfparent. Among others, I tried
the experiment with a young Cock ; which I wrapped in a cloth, in
order to keep him quiet, leaving out only his head ; and infpe6led
his comb, but could not therein perceive the motion of the Blood :
* Later writers contend, that the particles of Blood are not fpherical, as this word imports,
but plane, or of a flat (hape ; and tliis Mr. Leeuwenhoek admits to be true with regard to
fifhes. However, the word globules is always ufed to denote the component particles of the
circulating fluid.
f la fome fifhes the Blood is not of a red colour, and alfo in many infe<fls, which have been
therefore improperly denominated exfangues, or bloodlefs.
M
C 90 )
I afterwards examined his gills, or tliofe parts hanging under
the throat, and there I favv it running in an inconceivable num-
ber of veilels ; man}' of v;hich were fo minute, that numbers of
them taken together \Vould not equal the fize of a hngle hair :
but it was impoihble for me to trace the circulation in them, by rea*
fon of tlieir imraenfe number, crolfing each other in all diredlions :
for the rednefs which we obferve in a cock's comb and gills, proceeds
entirely fiom tlie great number of blood-velTels on their furface,
where they are only covered with a thin tranfparent fkin.
After this, I made my obfervations on white Rabbits, by placing
their ears before the microfcope ; but, with -all my pains, I could
not do more than fee the Blood running with great fwiftnefs througli
the ■arteries and veins. When I plucked oft" tlie ihort hairs from tlie
extremities of the ears, becaufe they obftrufted my fight, lobferved,
that the pulling off" each hair had broken or injured feveral of the
veflels, and caufed an effufion of blood. From hence I gatliercd the
rcafon, why I had perceived that the pulling out any hairs from the
back of my hand produced a rednefs in the part ; and I now con-
cluded, that we cannot pull out a fingle hair from any part of our
bodies, w hile fuch hair is growing, without injuring i'omc vefl'els, fo
as to caufc the Blood to flart.
But my greateft expectation of fuccefs, was placed on a Bat, be-
caufe I conceived that the membrane, or fkin, which ferves this ani-
mal for wings, muft be fo thin and tranfparent, as to afford a view
of the veffels. And, having procured one of thefe creatures, I put it
into a glafs and examined it by the microfcope. Here I fav/ the mo-
tion of the Blood, both in the arteries and viens, moft diftinflly, and
fully to my fatisfa(5tion, though by no means fo clearly as is to be feen
in f'ihes ; firft, becaufe the membrane compofingthe bat's wing, is
not fo tranfparent ; fecondl y, becaufe there is more of the watery part
(or ferum, as it is called) in the Blood of fiflies than in terreftrial
( 91 )
jfciiimals ; and thirdly, becaufe the particles of blood from which its
rednefs proceeds, appear much larger in fifhes, they being of a flat
and oval fliape; whereas, on the contrary, as far as I could judge
from my eye, they, in this animal were fpherical. I ufed every
means I could devife to fee the compleat circulation of the blood,
namely, that one of the fmalleft of thofe veffels which we call veins,
arofe from another which is called an artery, and afterwards con-
veyed its contents into a larger vein ; but this I found to be impoffi-
ble, for when I followed the courfe of the artery, until it became fo
fmall as only to admit one or two globules to pafs through it at a
time, I then loft fight of it. If this artery, throughout its circuit, had
not been fmaller than the twenty-fifth part of an hair, I do not doubt
that I could have feen the whole circulation ; but as thefe veffels
were at their extremities diminiflied to a much lefs fize, and the
membrane of the wing was covered with a kind of fcales, I could not
(as I have before faid) follow with my eye thofe minute ramifica^
tions. I perceived, however, in many places, an artery and a vein,
placed cloi'e bcfide each otlier, and of a fize large enough to admit
the pallage of ten or twelve globules of blood at the fame time ; and
in this artery the blood was protruded or driven forward with great
fwiftnels, and flowed back through the vein, which was a moft plea-
fmg fpeclacle to behold.
I could alfo moft plainly perceive in the arteries, the rifing, or pul-
fatioii, caufed by the motion which the blood receives from the heart ;
tlicfe pulfations were fo rapid that I judged feven ftrokes were per-
formed in a fccond of time.
The worm, or fmall animal which is produced from the fpawn of
frogs, and is called a tapdole, afforded me a ftill more diftin6l view
of tiiis fubje6l; for, upon placing one of them, which was newly
hatched, before the microfcope, I could diftinftly perceive the wliole
circuit of the blood, in its paflbge to the extremities of the vellels,
and in its return towards the heart. But I mull here obfcrve, (as
( 92 )
before mentioned) that if this blood had been an uniformly clear
liquor, its motion could not by any means have been difcovered ; but
as itconfuled of a very tranfparent fluid, mixed, as it I'eemed, with
globules of different iizes, which were plainly to be diftinguilhed,
though they had not, as yet, in this creature acquired any colour,
the circulation was thereby rendered very apparent.
When thefe tadpoles were about eight or ten days old, I could
perceive a fmall particle moving within their bodies, which I conclu-
ded to be the heart ; and the fluid which was protruded from it
began to afl'ume a red colour.
Upon examining the tail of this creature, a hght prefented itfelf,.
more delightful than any that my eyes had ever beheld ; for here I
difcovered more than fifty circulations of the blood, in different
places, \\'hile the animal lay quiet in the water, and I could bring it
before the microfcope to my wifli. For I faw, not only that the
blood in many places was conveyed througli exceedingly minute
velTels, from the middle of the tail towards the edges, but that each
of thefe veflels had a curve, or turning, and carried tlie blood back
towards the middle of the tail, in order to be again conveyed to the
heart. Hereby it plainly appeared to me, that the blood-vedels I
now faw in this animal, and which bear the names of arteries and
veins, are, m fadt, one and the fame, that is to fay, that they are pro-
perly termed arteries fo long as they convey the blood to the fartheft
extremities of its veflels, and veins when they bring it back towards
the heart. For example, I fee many blood-vefl'els in the tail of a
tadpole taking their courfe, as reprefented in Plate IV. fig. i. ABC,
where the pofition of the parts A and C is towards the fpine or mid-
dle of the tail, and the part B towards the edge of it. In A B, the
blood is driven from the heart, and in B C, it is brought back again,
and thus may we fay, that the veflel ABC, is both an artery and a
vein, for it cannot be denominated an artery, farther than where the
( 93 )
blood is driven in it to its fartlieft extent, that is, from A to B ; and
we muft name B C, a vein, becaiile, in it, the blood is returning
back to tlie heart. And thus it appears, that an artery and a vein
are one and the fame veflel prolonged or extended.
In the part where I faw this circulation, the arteries were no lar-
ger than to admit a fingle particle of blood to pafs freely through
them : thefe particles, though in this creature they were of a fiat and
oval fliape, yet fometimes by reafon of the fmallnefs of the artery,
all'umed a kind of oblong round figure, and when the animal, by
being taken out of the water, grew languid, the blood in thefe very
minute arteries began to ftagnate, and when it again acquired mo-
tion, many of the globules appeared twice as long as broad, and alfo
pointed at their extremities.
In another place, I faw a larger artery divide itfelf into two
branches, which are fliewn at fig. 3. D E, and each of thefe branches
returned back with a curve, as reprefented at E F and E G. Now,
if we denominate D E F, and D E G, arteries, becaufe, in them the
blood is driven outwards from the heart, it follows that F H, and
G I K, muft be veins, becaul'e they each bring it back towards the
heart. Again, not far from K, was another fmaller artery, which
is figured at M L ; this was united to the vein I K, fo that the
arteries D E G, and M L, together formed one vein at I K. In a
word, in this figure, H F is a vein, D E F and D E G, are arteries ;
G I K and K I L, are veins, and M L is an artery ; and yet we muft
fay, that thefe are only the fame veflels contHmed.
In another place I faw three of the fmalleft arteries, after return-
ing in a curve, as before defcribed, unite in one, and thus form a vein
three times the fize of each artery. But all thefe three veflels with
their bendings wherein the circulation was performed did not occupy
more fpace, than could be covered by a grain of fand,
I often perceived an artery, taking its courfe over, or croffing
( 94 )
a vein, and, if a perfon did not clearly fee the different courfes of the
vefl'els, he might concUide that here the circulation was performed
or compleatcd, and this I faw not only in the fmalleft velTels, but in
thofe which were ten times larger. This tranfverfe courfe, or cur-
rent of the veni'ls, I had often before obferved in terreftrial animals,
Avhilft I was endeavouring to difcovcr the conjun6lion of their arte-
ries and veins. But, as I became then well afllired, that this con-
jun6tion, or circulation, did not take place in the larger veflels, but
in the very fmallefl: of all, (for otherwife I am pcrfuaded, that all the
parts of the body could not be fupplied with nourifhment) and that
therefore I Ihould in vain attempt to difcover fuch circulation, I, fome
years ago, abandoned the farther inveftigation of it. For, if we now
plainly perceive, that the paflage of the blood from the arteries into
the veins of the tadpole, is not performed in any other tlian thofe
veffels, which are fo minute as only to admit the pallage of a fmgle
globule at a time, we may conclude that the fame is performed in like
manner in our own bodies, and in thofe of other animals. And if
fo, it mull be impofhble for us ever to difcover the padage from the
arteries into the veins in the human bod}^ or of any terreftrial aiii-
animal ; firft, becaufe a fingle globule, when lying in one of thofe
minute arteries, has not any vifible colour, and fecondly, becaufe, in
thofe veffels whicli are fo large as to come within our fight, the
blood has not any perceptible motion.
The particles in the blood of frogs are (as before obferved) of
a flat and oval Ihape, and thefe, when \iewed fingly, appear, as I
may fay, colourlefs ; but wlien two are laid on on.e another, tliey
appear a little of a reddifh cafl ; and v>here tlirce are together, tlie
rednefs becomes deeper. This may be explained ^y Jig- S- '^vlierein
A reprefents one of thefe oval particles, whicii, in part, is covered
by another particle B ; and C is a third particle, covering a fmall
part of both A and B ; by which means the part at D, where tlie
particles are three-fold, acquires a ffill darker colour. But when
( 95 )
I have attentively examined one of thefe oval particles on the ed^,
as is fcen at E, I have found it exhibit a flronger blcod-red than
where three particles lay flat one on another.
Among the tadpoles, which I caufed to be taken out of the canals,
I perceived a fevv' very fmall ii flies, having their fkins marked with-
dark fpots, fome of wliich were of the figures of little fiars. This fpc
cies of fifli I judged to be of its full fize, becaufe I had never feen any
by the naked eye of the fame fliape as thefe appeared v^hen magnified.
One of them I placed before the microfcope, and, upon obferving the
finny part which conftitutes the extremity of the tail, I plainly faw
the fame kind of flender arteries and veins as I have before defcribed,.
thiough with more difficulty than in the tadpole, partly, becaufe
this fifli did not long continue quiet, and partly becaufe the parti-
cles of Blood (which, in thefe obfervations appeared to me no
other than globules) were much fmaller than in the tadpole. Thefe
arteries and veins v-.ere placed near the boney parts, or rifings, v*hicli
give ftrength to the fn at the tail, and in them I faw the compleat
circulation of the Blood ; for, on both fides of each of the before-
mentioned boney parts was an artery, which had a bending, or back-
ward turning at its extremity, and thus became the beginning of a
vein.
Upon vievv'ing this fim's tail, at th.e part where the fin begins, I.
tliere faw, to my great admiration, a large artery dividing itfelf into
tlie before -mentioned fmaller ones ; and clofe to it, numbers of the
minute veins returning from the fin, and uniting in one large vein.
In fliort, here was fuch an agitation, or motion of the Blood driven
out of the large artery to the fartheft end of the tail and into the fin,
and running back in the fmall viens, into the large one, as is incon-
ceivable.
In order to Ihew the fize of this little fifli, wherein I obferved all
thefe motions of the blood, I caufed a figure of it to be drawn, as it
appeared to the naked eye, and this is fliewn in Plate IV. fig. 4. At
( 96 ) ^
fig. 5, is fliewn part of tlie body and the tail of the fame fifli, as fecn
through the microfcope. DE is a fin on the back, and L M, another
under the belly, near the tail, and FGHIK is the fin of the tail,
wherein are to be numbered feventeen fmall bones.
Thefe fmall bones, contrived by Nature to give ftrength to the
fin, were formed with joints ; and I could fee that they were com-
pofed of oblong particles, which, probably, were hollow tubes ; the
pellicle, or membrane, which covered them, and compofed the
greateft part of the fin, was alfo formed of oblong parts, but thefe
things the limner could not perceive, becaufe the fifli being then
dead, they were become invifible.
I have before faid, that on each fide of thefe boney parts of the
tail I had diflin6lly feen the compleat circulation of tlie blood, and
this was in thirty-four places, two between each bone ; that is, there
were in this fifh's tail fixty-eight blood vefl'els ; namely, thirty-four
arteries, and as many veins, befides tliofe vefi'els that, probably,
were in the fmalleft part of the fin, about F or K, wliich I did not
attend to.
To Ihew this circulation more plainly, I caufed one of the boney
parts of the tail to be drawn fomewhat more magnified, which is re-
prefented a^.fig. 6, O PQ R, Clofe to each fide of this bone lies an
artery, which in the figure is pictured at S T and W X, and in thefe
veflels are reprefented the particles of blood, which appear of a round
figure. Here the blood was to be feen running with a fwift courfe
from S to T, and with the fame fwiftnefs returning back from T to
V, fo that ST is an artery, and T V a vein, and yet, both of them
but one blood-veffel, continued and prolonged. In like manner, were
the blood-veflels on the other fide of the bone at WX Y. But thefe
arteries and veins were not at fo great a proportionate diftance as
here reprefented, for, in many places, they were fo clofe as to touch
each other.
( 91 )
In other places, and alfo in the two fins D E and L M, I faw the
blood not only running along, but alfo taking its \\'hole courfe for-
ward and back again, in manner before defcribed.
Now, if in the tail of fo fmall a fifli, as this which is pictured at
fg. 4, there are to be found thirty-four diftinft circulations of blood,
what an incredible number of them mud there be in an human body !
And this being fo, it is no wonder, that, upon the lead pun6lure made
by a needle, or any other fmail inftrument, the blood illiies forth. In-
deed, from thefe my obfervations, I am well afliired, that, in the
fpace of a finger's nail, in any part of the furface of our bodies, there
are more than a thouland circulations of blood.
Some years after thefe, and other obfervations of the like kind, liad
been made by miC, I accidentally fell into converfation with a certain
learned Gentleman, (not a native of Holland) on this fubje^l of the
circulation of the blood, particularly in the minuteft veflels which are
contained in a very I'mall fpace, and that this circulation could as
plainly be feen, as with tiie naked eye we fee water fpringing up
from a fountain, and falling down again ; but though I ufcd all my
endeavours to convince him of the truth of what I advanced, yet
this learned Gentleman refufed to give credit to my words, declar-
ing that he could not form any conception of the matters which I
related.
This Gentleman's incredulity took up much of my tlioughts, par-
ticularly upon a time when I had got Ibme very fmall eels, not
longer than one's little finger : and on this occafion I fcnt for a
limner, who I knew was a very curious obferver, and had a very
acute fight, judging that he would be able to make a drawing of fome
of thofe blood -vefleLs.
I then put one of thefe fmall eels into a glafs tube, about the fize
of a goofe-quill, and placing it before the microfcope, I delivered it
into the limner's hands, defiring him particularly to attend to the
current of blood which at that time was moft dirtin6liy to be feen in
N
( 9^ )
fome final] veffels ; defiring him, at the fame time, to obfcrve, that
all tho'e veni?ls thrcugli which t!ie blcod was driven outwards to the
cxtrcinitios, v>erc named arteries, but where the blood, when arrived
at the fmallefl veilels, began to take its courfe back again, there
they were called veins, although it plainly appeared that the vcllels
\\ ere one and the fame.
The limner could not fufTiciently admire this fpe6lacle of the blood
circulating in fuch minute velTels, arifing out of the larger ones ; and
he was equally in admiration at the blood's returning from thole
very fmall vefTels into the larger. And as the eel continued quiet
longer than ufual, without moving its tail, I frequently defired the
limner that he would, as long as pollible, keep his eye fixed on this
current of the blood, in order to imprint the idea on his memory.
At length, he put his hand to paper, and made a rough fketch of fome
blood-vellels and their ramifications, or branches ; and he repeated
liis obfervation and his drawing, until he had compleatly traced fix
fcvcral blood-velTels, namely, three arteries, and as many veins, witli
their ramifications, with all tlie accuracy he was able, faying, he had
now fufficient materials to make a perfeft drawing, fo as to dcfcribe
the cxa6l proportion both of the larger and fmaller vefiels.
In Plate IV. ^^. 7, and in the fpace between i , 2, 3, 4, are reprc-
fented fix of tliefe blood-vefiels, which I directed to be drawn on
rather a larger fcalc than the firft fketch taken of them, in order that
the fcveral veficls might be eafier difiinguifhed ; therefore this figure
(liews them about twice as large as tliey appeared to the limner
through the microfcope.
Thefe velTels were not at the very extremity of the fifii's tail, but
El little below it, towards the end of the fin. And that part, or fpot,
which the limner faw through the microfcope, and the feveral blood-
veflels of which he made the drawing, did not, in my judgment, take
up as much fpace as is occupied by a large grain of fand ; for though
the view of the microfcope might include the compafs of four fuch
( 99 )
grains, yet the part wliercin the blood-vefTels were feen, did not
amount to a fourth of that fpace ; fo that, within lefs corapafs than
that of a grain of fand, there are found to be in the tail of an eel, as
great a number of blood-veflels as are here re])refented between
1,2,3,4.
At the letter A, is reprefented one of thofe blood-veflels. which
are called veins ; B, one of thofe named arteries ; C, is a vein ; D,
an artery ; E, another vein, and F, another artery.
But, in order more clearly to explain the courfe of the blood in
thefe veflels, and to fhew, at what part, though in fa6l they are one
and the fame, they aiTume different names, 1 have in the figure more
particularly pointed out, and fliall now defcribe one of thole veflels
called an artery.
D, is that artery, out of which, at G, proceeds a fmall branch,
which, at H, divides itfelf into two, as HIK: and here we fee, that
the branch GH I is properly to be named an artery, becaufe, as far
as I, the blood is driven from the heart, and IK, we muft name a
vein, becaufe, from I to K the blood is brought back towards the
heart. In the other branch, which proceeds from H, in the dire61ion
H LM, the blood is infufed into the vein E at M; and fince at M it
firft begins to take its courfe towards tlie heart, it follov,s that at M
this veffel lirft alTumes the name of a vein.
In this fmall artery G H, it is to be obferved that the limner has
been very accurate in defcribing the exv.61 fize of the veflel, and we
mufl: always bear in mind, that in thefe branchings, or ramifications,
the arteries grow fmaller and fmaller, and the veins continually grow
larger, as they receive the blood from the arteries. Farther, all the
minute blood-veflels defcribed in this figure the limner has repre-
fented, not by lines, but by fmall circular dots, fo as to give an idea
of the particles or globules of blood, which he very dillinftly faw,
running or paffing through them.
All the minute veflels which are reprefented in this figure, of the
N 3
( 100 )
fize piftured at HIK, or HLM, are of equal dimenfions, and they
are fo flcnder, that I can fafely affirm, that if a grain of our common
fcowerino- fand were divided into a miUion of equal parts, each of
ihofe parts ^^•ould llill be too large to find a paflage through thefe
minute velfels. Which being confidered, we may conclude how
exquifitely flcnder muft be the veffels in which the circulation is per-
formed : and if it w^ere not fo, how could all the parts of our bodies
be continually fupplied with nouriihment ? *
Farther, in the before-mentioned artery D, is another fmall ra-
mification at N, which depofits its contents in the vein E at O, and a
little higher, at P, is a branch which unites itfelf with the vein
EatO.
At R, may be obferved another fmall brancli, proceeding from
the fame artery D, which, at S, is joined with a I'mall branch from
the artery B, and afterwards both fall into the vein C.
Again, at T,is another fmall branch, arifing out of the artery D^
^vhich, at V, fubdivides itfelf into two, and, in two feveral places,
namely, at W and X, conveys the blood into the vein E, and from
the fame artery another branch arifes at Y, which, at Z, is divided
into two, and thefe are united to the vein C at the places marked
a and b.
At a fmall diflance from Y, is another very minute branch at c,
which is joined to the vein C at d.
Farther, at e, another fmall artery branches forth from D, taking
the dire6lion ef, and at f is fubdivided into two ftill fmallcr
branches, both which join the vein E at ^ and b.
* A very eminent phyfician of our own country, (Dr Mead) exprcfles himfelf in
very nearly the fame words: " Every animal machine is of fuch a nature, that there is a
" fort of infinity in its conftituent parts, by which expreflion I mean, that their fibres are
" fo extremely fmall, that we cannot difcover the ultimate ftamina, even by the aiSftance
" of the beft microfcopes. Had it been othcrwife, aliment could not be conveyed to
« every individual part of the body ; nor could the neceflary funcSlions of life be pcr-
" formed. Mead's Medical Precepts, in the IntroduSiim.
( 101 )
A little higher in the artery D, a Imall artery branches off at /, pro-
ceeding to k and /, where it again divides itfelf into two, and joins
the vein E at m and 7i.
Clofe to /, two Imall branches arife at o, and join the vein C at
p and q.
At /■ arifes another fmall artery r s, which at s divides into two
mailer branches, one of them taking the courfe s t, to join the vein
C, and the other paffing by s u zv x, to join the vein E.
Lallly, the extremity, or Imallefl part of the artery D, is fliewn
at ry z, and is united to the vein E at A, firft fending oii^' a branch
jiear the letter ?<, which taking the direction u b, is united to the
vein C at t.
Hence it plainly appears, how many various branches or minute
arteries proceed from thofe fmall blood-veflels, or arteries, repre-
iented at B; D and F, and how thefe all unite wuth the other fmall
veflels called veins, which are (liewn at A, C and E ; and this alfo
proves what has been fo often mentioned, that all thefe blood-veliels,
tiiough called by ditierent names, are yet the fame identical velfels.
And if we reflect, that each of thefe very fmall veflels mufl: be
formed with the fame kind of coat as the larger ones though of a
thinnefs proportioned to its fize ; and farther, if we confider of
wliat wonderfully fine and invifible membranes the coats of the
fmalleft veffels mufi: be formed, and how eafily the finefl: part of the
arterial blood may find a paflage through thofe coats, to the end that
every part of the body may, from thence, be continually fupplied
with necelTary and fuitable nourifliment ; thefe things, I fay, be-
ing duly weighed and confidered, it feems clear that tlie arterial
blood, coming from the heart, mud contain more fubtile and fluid
parts than when in its paflage to the heart. For the blood will not
be deprived of its more fubtile juices, while in the larger arteries;
to prevent which, I imagine that they are provided with thick and
folid coats. And here the particles of blood from which its rednefs
proceeds, fwimming in a thin juice, are of a bright red colour; but
( 102 )
in the rmallefl; arteries, fome of its parts are drawn off for thefupport
and nourirhmcnt of the body, wliereby the blood, when returning
in the veins, being deprived of thofc thin juices, aifun^es a darker red,
and as more of the thin juices are taken away, it will appear blackifn.
Tlie circulation of the blood is reprelbntcd in another view, at
fg. 8, A B C D E F G H I K, which is a drawing of fome veflbls feen
by the microfcope, in the tail of a tadpole ; thefe animals are much
quieter than eels, and the arteries and veins are as eafily to be feen
in them as in any other creature ; and in the fmalleft veilels where
the period, or the retrograde motion of the blood is performed, its
particles are more diftant from each other than in any other aniinal.
The veilel, fliewn in this iigure, (which was an artery, wherein
the blood was driven fors\ard with great fwiftnefs from A to B) was
rather larger tlian to admit one of the particles of blood at a time.
At B it divided itfelf into two branches, which are re])refented at B C
and BE; thefe two branches were at D again united in one, for
a fhort fpace, and at F they again feparatcd, as fliewn at F G and
F I. Here thefe two arterial branches, making a fmall curve, or
bend, again joined in one at H, forming a fomewhat larger vefliel,
which is feen at H K , and at K, this was joined to a (till larger
blood-velTel.
Here it is plain, that the veflels A B C t) E FG, and ABEFI,
forafmuch as in them the blood is driven from the heart, to G and
I, its greateft dillance, muft be named arteries ; and the veflels G H K
and I H K, becaufe in them the blood is returning to the heart,
muft be named veins.
I formerly was of opinion, that in all cafes where by an accidental
fall or blow, there were produced livid or purple fpots upon the
Ikin, which proceeded from coagulated blood, this blood (if no
exulceration fliould take place in the part) would by degrees be lb
diflolved, as to be carried off by perfpiration ; but the following
fervations caufed me to alter my opinion in this relpebl.
( 1^3 )
In the tail of this tadpole, I obferved a vellel, of a fize to admit
twenty of the particles or globules at once ; fo that this was a large
veilel, in proportion to thole which I have before defcribed. A fmall
part of it is reprefented 3-tJig. 9, L M ; and from tliis, proceeded a
minute veflel, which is fliewn at M O.
The current in this veflel, from L to M, was not ib fwift as I ob-
ierved in the other veffels, and for this reafon, that, in another part
of it, at R, the blood was coagulated, infomuch, that no diftinft par-
ticles could be perceived in it, but only an uniform rednefs ; but in
the fniall vellel N, the current was as fwift as in any of the others.
In confequence of this flagnation at R, the blood was driven for-
wards from M to P, with every pulfation of the heart, and inftantly
ran back again, in like manner, as if with the naked eye Me beheld
a fwift alternate or reciprocal motion, like that of a faw.
\Ye know, that water cannot be compreffed into a lefs fpace than
it naturally occupies ; and this being alfo the cafe with regard to the
blqod, -we muft conclude, that the coat of this veflel, between N and
P, and alfo a little below N, was, at every pulfation, expanded in
diameter, and, at the intermitting of the pulfation, would contra6t
itfelf, and fo drive the blood back ao;ain.
Keeping my eye fixed on the obje6l, I perceived, in a little time,
the blood between P and R begin to move, and by little and little,
from P toM ards R, to have the fame alternate motion to and fro, as
I have before defcribed. At the fame time, the blood in the veflel
N S, where, at firft, little or no motion could be feen, the current
\vas nov/ as fwift as ufual. And in the fmall blood-veflel, marked
V O, which was only of a fize to admit one globule at a time, and
wherein I could not at firft difcover any motion, the circulation was
now reftored ; but the particles of blood were few in number, and at
a diftance from each other.
( 104 )
At length all the blood from P to R, was fo far rendered fluid, that,
at every pulfation, it was driven forward, and tlien returned back
again. In thefe obfervations, about two minutes of time elapfcd,
and my eye being fatigued, I took it off the object to give it reft, in
which interval, the animal put itfelf into a violent agitation, there-
by precluding any farther obfervation.
But, fince we now clearly fee, that coagulated blood can, by the
pulfation of the heart, in courfe of time, not only be put in motion,
but alfo fo far diffolved, that its component particles or globules may
re-afiume their prifline figure, we may fairly conclude, that blood,
in any animal, which by a blow or bruife, is made to coagulate and
ftagnate in the vefl'els, may, in the fpace of fome days, be reltored
to motion,
60 For, fuppofms:, that in an hu-
man body, the blood is driven
4500 an hour. f^.^^^ ^j^^ j^^^^^. feventy-five times
in the fpace of a minute ( fome fay
18000 ' \ J
90 the number of pulfation s does not
108,000 a day anJ a night. exceed fixty, but I belie\'e my
[f computation to be neareft the
i,o8c,ooo ten days. truth) it follows, that the pulfa-
tions in an hour's time, are 4,500,
and, in the fpace of a day and a night, 108,000.
Now, if we find, that the appearance produced by coagulated blood,
will, in the fpace of ten days diHippear, from our bodies, and confi-
der, that, in the fame fpace of time, a million and eighty tiioufand
pul Cations are performed, and fuppofing, that, at every pulfation, fo
much of the blood is put in motion in the feveral veflels, as is only
equal in fize to a grain of fand, we may gather how much of flag-
nant blood may be reftored to motion, in the fpace of time juft men-
tioned.
For example, let us fuppolc, that tlie quantity of blood, ^'(^
which at every puliation can be rendered fluid, and reftored
to its motion, is no more than the fize or quantity of a grain ''"'^g,,
of fand, and that eighty of fuch grains placed fide by fide do • " •
111 I r • 1 !• 1 1 1 512000
not exceed the length of one nicli ; we hnd then that 512000 .
grains of fand taken together are equal to a cubic inch, which num-
ber is not the half of the number above affigned.
In this blood-veffel, which I have jufi: mentioned, I could not only
very clearly difcern the feveral pulfations, but I could alfo many
times in all the arteries, fee to make an exa6l computation how
many times the blood was propelled from the heart in the fpace of one
minute.
Now, if we confider that fo great a quantity of blood, as is con-
tained within the compafs of a cubic inch, is very rarely by a blow
or bruife congealed in one fpot, we may eafily conceive, that when a
coagulation does happen, it may, by fuch frequent propulfions or
pulfations as I have mentioned, be at length dillblved, and in all, or
mofi: of the vefllels, reflored to the fame current or courle as before.
At another time, I obferved an appearance of a different nature
in the blood- vefTels, which was occafioned by my having put a tad-
pole into a piece of clean paper, whereby a fmall fpot in the very
thinnefi; part of its tail ftuck to the paper, and thereby received a
fmall injury, fo that fome blood flowed from the wound, out of an
artery which was of a fize to admit about four globules of blood to
pafs through it at a time.
The blcod thus flowing out, remained collected about the wound-
ed part ; but here another fight prefented itfelf, wliich engaged all
my attention; for, in this fame artery, at about tlie half of an hair's
breadth diflancc from the wounded part, another fmall branch ap-
peared, wlierein the blood purfued its courfe in the fnne uniform and
diftin6l manner, as if the artery had remained uninjured.
O
( loS )
At fg. 10, TV, is feeii this artery, ^vhicll was wounded a little
above V. The letters V and X indicate the extravafated blood. V
W denote the minute artery in which the blood purfued its regular
courfe, though clofe to the place, at P, it ill'ued out from the artery
TV.
This fight at firft furprized me, but my wonder ceafed when I
obfcrved that tiiis blood vellel V W, was united with a large one at
W, and of that fort whicii, carrying back the blood to the heart, is
called a vein. And by means of this laft-mentioned velTel, the blood
was carried through the paflage V W, as it were, by a kind of fuc-
tion, with as much Iwiftnefs as it had been before driven from T to
V, infomuch that I was perfuaded, that if the fniall velTel V had not
been united to the artery T V, but ojily its orifice liad laid in the
extravafated blood, about the fpot at V, that fuch extravafated blood
would in a ihort time have been, as I may fay, fucked up and car-
ried away with the remainder of the blood towards W.
I have often reflefted on the nature of thofe very thin tranfparent
pellicles, or (kins, which conftitute the wings of fmall flying infedls,
fuch as gnats, flies, moths, and the like ; fome of which I have
obferved to be entirely covered witii feathers, others compofed only
of thofe mufcular parts which flrengthen and expand tlie wing, and
others arc wholly covered with hairs : and when I confidercd, tliat
thcfe hairs, or feathers, are fixed or rooted in regular order in the
membrane of the wing, my thoughts were wholly bent to difcover
how thefe wings might be formed.
As to the fuppofition which at firft occured, that thefe membranes
were compofed of a tranfparent vifcous or gummy matter, congealed
or hardened to a due confiflence, I could not fatisfy myfelf with
that idea, for it feemed impoffible to me, that in that cafe the feathers
and hairs could be produced in fuch regular order ; and yet, it was
beyond my compreiienfion how fo thin a membrane could be furnifli-
C 107 )
ed with fuch a number of veins or velTels as would be requifite for
the formation of fuch feathers and hairs.
In my endeavours to inveftigate this fubie6t, I firft examined one
of thofe flying infedts, whofe wings confill of membranes only,
without either hairs or feathers ; which membranes are placed
between the large veffels and fmews, giving ftrength and fliffnefs to
tlie wings ; and upon the examination of thefe, I plainly faw that
there were large blood-velTels running among the fmews or mufcu-
lar parts, from which arofe fmaller vellels, and thefe again divided
thcmfelves into flill fmaller ones, until at lengtli they became
invifible.
I was not, however, content with this, and among other obje6ls,
I met with a large green grafshopper, in tlie wing of which I more
clearly perceived not only, that from tlie large blood-veflels in the
wing, other fmaller ones arofe, but I alfo faw that the colour of tlie
blood in thefe large veflels was green ; and in the fmaller veffels and
their more minute ramifications, I could ftill diflinguilli tlie blood to
have a greenilh caft ; but when tliefe veflels were again fubdivided
into fmaller ones, I could not perceive any colour in them, and the
velfels themfelves became ib clear and tranfparent that they entirely
efcaped the fight.
Tliough I could mofl: plainly fee tliat the fubflance, or matter,
of which this blood was compofed, confifled of globules fwimming in
a clear liquor, I moreover cut the wing in two, and out of the veflels
collected fome of tlie blood, which I placed before the microfcope,
and obferved that where the globules or particles of it lay in numbers
or heaps together, tlie colour was a lively green, wliere they lay fo
thin as not to amount to the twentieth part of the thicknefs of an
hair of one's head, the colour was only greenifli, but where tlie
globules were fingly dil'perfed, it had no longer any appearance of
colour at all, but becanic tranfparent , and hero it clearly appeared
( io8 )
to me, tlicit all thefe green globules were contained in a thin tranfpa-
rent fluid.
From thefe obfervations I concluded, that tlie tranfparent mem-
branes which principally conftitute the wings of thefe fmall animals,
are as completely provided with blood-velTels, finews, &c. as the
bodies of other creatures.
I formerly was of opinion, that in the wings of thefe fmall flying
treatures tliere was no circulation of the blood, for I judged, that in
its paffage through fuch exceeding flender vell'els, it mull be evapo-
rated or dried up : and the rather, as many of thefe winged infG(51:s do
not take any food, but only live a few days, and die as ibon as they
have coupled, and laid their eggs. But if we recolle6l, that the mem-
branes of their wings are of a hard and horny nature, though exceed-
ing thin, we may conclude, that all the vefl'els, compofmg this liorny
membrane are fo firm and tough, that, though all the fluid con-
tained in them fhould be dried up by the heat of the fun, the vell'els
thcmfelves would not coUapfe or flirink up, as thofe in our own
bodies, or the bodies of other animals would do in the like cafe.
I was confirmed in this opinion, by obfcrving that the blood-vef-
fels in the wings of thefe infe61:s were not of the fame make as thofe
in the bodies of the human fpecies and of terreftrial animals, but were
compofed of annular parts, or rings, like the windpipe and the vefiels
pertaining to refpiration in tiie lungs of animals. And, though we
may not be able to difcover ^ill thefe velTels in the wings of infefts,
yet we may be afllired that tliere is an incredible number of them
entering into tlie compofition of thofe wings. And, fliould we ima-
gine, that thefe vcllels by reafon of their fmallnefs or their hard and
dry nature, are impervious to blood and juices for the fuflenance of
the wing, we mull confider that there is not a fingle hair or feather,
how fmall foever it be, which is found upon one of thefe wings, but
muft have had in it many fmall vefiels neceilar}' for its produ6lion ;
for every feather has its quill and every quill mufl have a great iium-
( 109 )
ber of veffels, in order to contribute to the increafe of fiich feather :
and who knows whetlier each of fuch fmall feathers may not have
been formed out of more than a thoufand vefTels ? And when we
reiie6l on the great number of feathers or hairs with wliicli the wing
of a fly or moth is covered, we fliall find it impoflible to conceive
the numbers of vcflels of which thefe infe6ls, though they appear
contemptible in our eyes, are compofed. Indeed, I am of opinion,
that many phyficians and furgeons cannot reckon up fo great a
number of veHels in a cat or a dog, as I imagine enter into the com-
pofition of a gnat.
It was alfo at one time my opinion, that the ridges, or thicker
parts, in the wings of thefe flying infers, and which 1 have named
fmews, were only the boney parts of the wing to give it ftrength.
But when I perceived, that there were large blood-veflels in thofe
parts, I applied myfelf with all diligence to dilcover, if pofllble,
the current of blood in tiiofe vedels.
For this purpofe, I took thofe butterflies which ]:)roceed from
the catterpillar that feeds on the afpin, the poplar, or the willow ;
and which, in fize and fhape, refemble the filk worm's butter-
fly. Their wings are, on both fides, covered with white feathers,
and, unlefs thefe are taken off, the membrane cannot be dif-
cerncd. Thei'e feathers I wiped from the wing witli a foft piece
of leather, as gently as poflible, to avoid injuring the wing or
hurting the butterfly. And I then applied the wing (while the
animal was alive) to the microfcope ; but, with all my attention, I
could not difcern the leaft current of blood in the veflels, thouah
if there had been any regular motion, I have no doubt but I fliould
have ieen it, and the rather, as this blocd was of a yellowiOi
colour; and, upon opening the large veffels in thefe wings, I have
often prefled out the blood which they contained.
For tiie moft part, thefe large velTels lye in, or near, that boney
part of the wing which gives it ftrength; and I have often obferved
( 110 }
thofe velTels to be placeJ, not in a right line, or parallel with the
honey part, but twilled, with various turnings, in like manner as
if one were to fee the intellines of an animal in the pofture they lie
while joined to their membranes.
After this, I accidently met with a large grey moth or butter-
fly, which in a manner flew into my hand. This butterfly I killed,
and cut oflf' the wings, and, having taken off the feathers, I
placed them before the microfcope : and here I faw the blood-
veflels more plainly than in the wings of the other infe6ts I have
mentioned. A part of one of thefe wings I placed before the
mici'ofcope, and caufed a drawing to be made, not only of thofe
blood-velT'els lying in the boney part of the wing, but alfo of thofe
which were difperfed over tlie membrane, and of which the mem-
brane, in part, confifts ; in order to Ihew, how the vefTels lye
twifted in various turnings ; alfo, how they are compofed of annu-
lar parts or rings placed together ; and likewife, how, from thefe
large veflels fmaller branches arife, which, in great numbers, are
fpread all over the membrane.
In Plate IV. fg.ii, POR reprefents a blood-veffel, with its
various branches, I'pread over the membrane. ABCDEFG, is
a large blood-vcffel in one of the boney parts of the wing, wherein
is feen, the manner how this veiTel is twifted or bent, and alfo, the
annular parts of which it is conipofed ; in conformity with the
formation of tlie blood-vellels in all infc61s ; infomuch that I have
ieen the blood-veflels in the loufe and flea, to be compofed of fuch
annular parts.
In the fame figure, B H, I K, C L, DM, EN, and E O, repre-
fcnt tlie blood-vellels with their branches ifl'uiiig from this laft-
mentioned veffel, and fpreading over tlie membrane ; and in tiiefe
alfo, the annular parts could be diflinguiflied ; but when they
became fo fmall, as to appear no larger through the microfcope,
than a horfe-liair to the naked eye, then the rings in tiiem could
no longer be difcerned. Thefe veilels the limner purfued in his
( ^^t )
drawing as far as his eye could diftinguifli them, but at length they
became lb minute, and fo intermixed one with another, that no
true judgment could be formed of them.
In S T V, are fhewn a few of the feathers, which fo exa6tly cover
both fides of the membrane, that no part of it can be feen. W W
W, are three larger feathers which were placed on the edges of the
wing. XXXXX indicate the membrane, when it was laid bare of its
feathers, on both fides, in order to difcover the blood-vcflels. And
here, though not in regular order, may be ^een the cavities or holes
in which the quills were fixed, and from which ihey had their origin.
Farther, I confidered with myfelf, whether or no the blood-vefiels
confifted of arteries and veins ; but I could not fee any other than
one fort of veflels in the wings of all the infe6ts of this fpecie^, which
I have examined, except that once I thought I faw in the thinneft
part of the v/ing of a grafshopper, that in the larger vefiels next the
body, another fpecies of veflels vvas inferted.
The conclufion drawn by me upon the whole'was, that there was
not any circulation of the blood in the wings of tliefe creatures, and
that the blood-venels I have been defcribing, which certainly were
arteries, were only defigned to perfe(51: the formation of the wing with
its multitudes of feathers, and afterwards, to convey the blood, with
an exceeding flow motion, through the veflels, in order to afford a
fmall degree of fupport to the wing in its perfe6t ftate. For, as
thefe butterflies, and thole Avhich are produced from the filk-worm,
and many other flying infedls which proceed from caterpillars, do
not take any food, and do not live any longer than till they have
coupled and laid their eggs, it is not neceflbry, in my opinion, that
the blood in their wings fliould have any circulating or retrograde
motion, and befides, the membranes being of a fiift' horny nature,
they require little or no nourifliment.
I cannot here omit to mention, that I have heretofore often taken
( 11^ )
great pains to difcover two kinds of vcflcls in the leaves of trees and
plants in order to al'certain, whether there was any circulation in
leaves, but I never could lee more than one fpecies of velTels, namely
thofe tluit convey the nutritive juices to .the feveral parts.
But, if we confider, that not only the leaves of trees, but alio their
fruits, do not need any other than thofe nutritive juices, which are
requifite to bring them to perfe6lion, we fliall not wonder that when
at a date of maturity, they are, as it were, fpontaneoufly loofened
or fliaken off from the tree, without the lead appearance of having
been broken off; nay, that part of the flalk which was originally
united to the tree, will appear as fmooth as if, with its multitude
of veffels, it never had been joined to it.
In a word, I will venture to adert, that neither the wings of the
before mentioned flying infects, nor the leaves or fruit of trees,
require that kind of circulation of the juices, which we have been
confiderine:.
4-
Of the formation of the Teeth in feveral animals ; the flruclure of the
human Teeth explained, and fame of the diforders to which the fame are
liable accounted for.
XJlAVING taken great pains to invefligate the formation of the
elephant's tooth, and exanihied into the nature of it by every means
I could devife, I found it to confift only of a collection of tubuli, or
pipes, which are exceedingly fmall, and all derive their origin from'
the inner part of the tooth, for I never could difcover any of them
lying longitudinally or lengthwife in it.
Upon examining that part of the tooth where the honey fubftance
is but thin, which is where it is united to the head, I very- plainly
perceived that one end of thefe tubuli took its rife from the cavity
"within, and the other end extended to the circumference, which cir-
cumference or outfide was compofed of a kind of fcaly particles laid
one on another, and I confidered with myfelf whether each feries or
layer of thefe fcaly particles might not be the fubftance or tliicknefs
formed in the fpace of one year.
Purfuing thefe my obfervations in the examination of that part of
the tooth where to the eye it feems perfe6lly folid, I there found it
to have, near the middle, a fmall cavity, through which cavity I con-
cluded the nutritive fubftance muft be conveyed, for the continual
fupport and increafe of the tooth. And upon examining the tubuli
round about this fmall cavity, I perceived that they all arofe from
thence, and fpread themfelves all round towards the circumference.
I endeavoured to examine ftill farther, beyond the part where this
eavity ended, in order to difcover whether from thefe firft formed
P
( ^n )
tubuli otliers miglit notarife or branch forth ; but this part of nature's
work was infcrutable to me. My conje6hire refpe^ting the matter
however was, that each of the boney tubuh (proceeding from the
fmall cavity before mentioned) miglit be compofedof many folds or
coats, and thus not only be diipoi'ed to diverge or fpread into a
larger fpace, fo as to form the fubftance of the tooth, but alfo, by
this means, contribute to its ftrength.
I alfo examined the teeth taken from young hogs, and found them
to be likewife formed of tubuli fpreading from the cavity m the cen-
ter, to the circumference.
After this, I was defirous of examining the flru6lure of the hu-
man teeth, and having for that purpofe procured a number of the
large ones, called tlie grinders, I found them to be formed exadlly in
the manner before del'cribed, namely, of tubuli or little boney pipes,
clofely joined together, arifing at the cavity in the middle of the
tooth, and ending at the circumference or outfide. And in order to
explain this formation to the Reader as clearly as pofTible, 1 caufed
the following drawings to be made :
In Plate V.fg. i, at A B C, is rcprefented a human tooth, on one
fide of which, with a file, I cut away almoft the half, not to difcover
the cavity thereiji, which is well known to moft perfons, but only to
fhew the manner how the tubuli, of which the boney part is compo-
fed, take their rife from the cavity in the center, and terminate at tlie
circumference. But it mufl be underftood, that tliefe tubuli are by
no means of the fize rcprefented by the lines in this figure, the fame
only denoting the order in which they lie, for the tubuli themfelves
are exceedingly fmall, and cannot be well difcerned without the help
of the very beR microfcopes.
In the fame figure, at G H I, is reprefented another tooth, which
is filed down from the upper part of it as far as the before-menti-
oned cavity, in order to fliew how the tubuli do here alfo fpread
themfelves round about from the center. All the extremities of tlie
( 1^5 )
tubuli which lie near the oiitfide of tlie tooth, (as far as they are-
above the gums, and expofed to the air) are extremely hard, being
as it were the folid cafe, ihell, or covering of the tooth ; and if we
examine the furface of this cafe or covering attentively, we fliall find
one tooth to have forty, another perhaps fifty circles on it, like wrin-
kles, or gatherings, which in fome places run in a curved or wavy
dire6lion, as is reprefented in the figure at D E F, where a drawing
is given of this outfide fhell, with fome of the circles marked there-
on ; and I imagine that the circles which thus appear like wrinkles
proceed from hence, that tiiey are the places where the tooth, while
growing, is from time to time protruded or thruft out from the gum.
In the teeth fhed by children, and likewife in thofe of many young
animals, I have obferved that the ends of their roots are entirely
open or hollow ; and in like manner I imagine that the roots of the
molar teeth or grinders which I have been juft defcribing, are at
firft formed in the fame manner, but that in procefs of time tliev
become oflified or converted into a boney fubftance, of a fpongy
nature, through which many vefiels pafs, conveying blood, and nutri-
tive juices into the cavity of the tooth, and I alfo conceive that this
cavity is filled with nerves and vefTels fpreading themfelves into fo
many branches, that every one of the boney tubuli is thereby in-
creafed during the time of its growth, and afterwards, (while the
tooth continues found) nouriflied and fupported. 1 alfo conjedlure
that thefe fmall vefTels thus nourifhing and fupporting the boney
tubuli do not end at the furface of the tooth (I mean, in that part of it
which is within the gum ) but that the aliment or nutritive lubftance
has a continued courfe through thefe vefTels , and that the ends of the
boney tubuli are again converted into fofr or pliable veflels, fpread-
ing through the gum, and that thofe veflels are what principally keep
the tooth fixed in its place.
The firfl formation, and fubfequent fupport or nourifhment of the
( ii6 )
tooth being as before defcribed, we may eafily conceive that the
boney tubuli, (being of a folid nature, and incapable of dilatation or
fprcading) may happen to be obrtruited by fome grol's or concreted
matter, and then the fmall velTels contained within the cavity of the
tooth mufl: immediately by fuch obftru(^lion in the circulation of
their juices be dellined. This diftention or fwelling will necellarily
excite great pain, for all the vellels contained in the tooth will prefs
clofely on each other, foral'much as they cannot fwell or fpread
themfelves as other veflcls can, which are not confined within the
folid fubftance of a bone. Again, fuppofing thefe boney tubuli to be
obllru(51:cd, and the obflru61:ion not removed, we may from thence
gather the reaion why our teeth partially decay, fometimes on the
fides, and fometimes at the tops, the reft of the teeth remaining
found for feveral years after.
In order to flievv the proportion which the fize or thicknefs of the
tooth bears to its component parts before defcribed, I placed a very
fmall piece of this tooth before the microfcope, and delivered tliat
microfcope to the limner, directing him to draw an exac^l reprefen-
tation of what he faw, (but without acquainting him what that objetfl
was). And here I muft obferve, that in this tooth the tubuli appear-
ed to me much larger than I had before obferved in any animal, or
in the elephant's tooth.
In Plate V. at fig. 2, K L M N, is reprefented * an exceeding
fmall particle, or piece of a human tooth, of that fort called the
molar teeth, or grinders, as feen through the microfcope. The reafon
why in this figure fome of the tubuli there pictured appear of a
darker fhade than the reft, is only this, that in that place where
they feem darker there were more of the tubuli lying one
* The author having jufl: below informed us, that 120 of the boney tubuli make only the
forty-fifth part of an inch, we may, by counting the tubuli reprefented in this figure, judge the
natural fizc of the fragment, or piece of tooth here magnified, and it will be found to be about
the fortieth part of an inch in Isngth and the fiftieth part of an inch in breadth, or of the fize
(hewn at X.
( 117 )
behind the otlier, owing to the piece of tooth being thicker in that
part, for this fmall fragment was fpht off, and not cut from the
tooth.
The breadth of this tooth was ahnofi: two fifth parts of an incii,
and from the befl: computation I could make, I judged that within
the forty-fifth part of an inch, I faw an hundred and twenty of
the tubuh, which amounts, in the fpace of one inch in length, to
five thoufand four hundred : now fuppofing this molar tooth, or
grinder, before defcribed, to be of a round figure, the diameter of
it would be 2150 times the thicknefs of one of the tubili of which
the fame is compofed, and when this number is multiplied into itfelf,
the produ6l is 4,822,500. In a word, the proportion of one of
the boney tubili to the fize of fuch a tooth, is as one to 4,822,500
Notwithftanding I had now obtained a very fatisfadlory infight
into the formation of the human tooth, I was not yet content, but
became defirous to examine into the nature of the fubftance, or
veflels contained in the cavity, and for this purpofe, I procured
I'ome of the fore teeth, and the jaw-bone of an ox, which were
taken out and brought to me immediately after the animal had been
killed ; feveral of thefe fore-teeth, and fome of the grinders, I broke,
or fplit open, and with great admiration obferved, that thofe veflels,
which, palling through fmall apertures in the lower part of the
tooth, filled ail the cavity within, confifted of fuch an inconceiv-
able number of blood- veflels, and other veflels, as to furpafs all
imagination: indeed, many of them. I obferved to be as fmall and
flender as the tubili themfelves, of which the tooth was formed ;
and among them were fmall blood-veflels branching out into fiill
fmaller ones, many of them entirely colourlefs; therefore, I thought
it probable that there might be ftill fmaller veflels entirely undif-
cernible by our fight.
All thefe veflels were inclofed in a membrane, or coat, which
was eafily to be feparated from the bone, and, having kept fome
( ii8 )
of thefe teeth by me four or five clays before I broke them open,
(in which time all the internal nioilhn-e was evaporated), I obferved
in fome places within the tooth, a bloody fubflance which had pene-
trated into the boney tubuli, giving fome of them a reddilh colour.
It is my cuftom, every morning, to rub my teeth with fait, and
afterwards to walh my mouth, and after eating I always clean my
large teeth with a tooth-pick, and fometinies rub them very hard
with a cloth. By thefe means, my teeth are fo clean and white,
that few perfons of my age * can fliew fo good a fet, nor do my
gums ever bleed, although I rub them hard with fait ; and yet I
cannot keep my teeth fo clean, but that upon examining them
with a magnifying glafs, I have obferved a fort of white fubRance
colle6led between them, in confiftence like a mixture of flour
and water, hi reflecting on this fubflance, I thought it probable,
(though I could not obferve any motion in it,) that it might con-
tain fome living creatures. Having therefore mixed it with rain
water, whicli I knew was perfeffly pure, I found, to my great
furprile, that it contained many very fmall animalcules, the mo-
tions of which were very pleafing to behold. The largeit fort
of them is reprefented in Plate "V-fg. 3, at A, and thefe had the
greateft, and the quickeft motion, leaping about in the fluid,
like the fifti called a Jack ; the number of thefe was very fmall.
The fecond fort are reprefented at B, thefe often had a kind of
whirling motion, and fometimes moved in the dire61:ion repre-
fented by the dotted line C D, thefe were more in number. Of
the third fort, I could not well afcertain the figure, for fometimes
they feemed roundifti but oblong, and fometimes perfedlly round.
Thefe were fo fmall, that they did not appear larger than repre-
fented at E. The motion of thefe little creatures, one among
another, may be imagined like that of a great number of gnats, or
flies fporting in the air. From the appearance of thefe, to me, I
* Mr. Leeuwenhoek, at the time of writing this, was upwards of fifty years of age.
( 119 )
judged tliat I faw fome thoufands of them in a portion of liquid, no
larger than a grain of fand, and this hquid confifted of eight
parts water, and one part only of the before-mentioned fubftance
taken from the teeth.
With the point of a needle, I took fome of the fame kind of
fubftance from the teeth of two ladies, who I knew were very
2)un6lual in cleaning them every day, and therein I obferved as
many of thefe animalcules as I have juft mentioned. I alfo faw
the fame in the white fubftance taken from the teeth of a boy
about eight years old ; and upon examining in like manner, the
lame fubftance taken from the teeth of an old gentleman, who
was very carelefs about keeping them clean, I found an incredible
number of living animalcules, fwimming about more rapidly than
any I had before feen, and in fuch numbers, that the water which
contained th.em, (though but a fmall portion of the matter taken
from the teeth was mixed in it,) feemed to be alive.
Some time after making the preceding obfervations, I received
from Sir Hans Sloane, a packet, containing three fmall maggots,
two of which were dead, and the third alive, with a letter, inform-
ing me that they were found in a perfon's decayed tooth, from
whence they had been expelled by fumigation. Upon examining
thefe, I had no doubt that they were of the fort found in cheefe,
and upon comparing them with fome living ones which I procured
from a cheefemonger, I found them to correfpond exa611y in make
and fhape. Thefe maggots are the offspring of a fmall fly, whicii
is frequently feen in clieefemongers' fliops, and lays its eggs in
the cheefe, where tlie little maggots produced from them find
nourifliment, and are in time converted into flies.
The maggots fent me by the cheefemonger, I kept in a glafs
tube, and fupplied them with food, and in a fhort time they were
converted into flies, which laid eggs, and thefe again produced
maggots of the fame kind as the former. The living maggot
( 120 )
which I received from Sir Hans Sloane I kept by itfelf, and it was
alfo converted into a fly of tlie fame fpecics.
Thefe maggots when firfl hatched from the egg, are no bigger
than a grain of fand, but afterwards grow to about four times that
fize ; they have two fmall teeth by wliich they are enabled to gnaw
tlieir way into the cheefe ; and as their fkin is very firm and hard
they are not eafily cruflied or deftroyed. Now, it is eafy to con-
ceive, that the perfon in whofe tooth the maggots firft mentioned
were found, might have been eating of fuch old cheefe, and that
the maggots, or the eggs producing them, might have been lodged
uninjured in the cavity of the tooth, where, when they began to
gnaw, they muft caufe great pain ; and we may elfo eafily imagine
that by the fumigation they might have been driven out of the
part.
ON COFFEE.
J.N my inquiries i)ito the nature of feveral kinds of feeds, I examined,
among others, thofe which are called Cotiee Beans, which are much
in life in this country, for preparing the well known drink of that
name.
I was firft defirous to know in what part of thefe feeds the young
plant was placed, and for this purpofe I procured fome entire coffee
beans, inclofed in their original hufk or Ihell.
In Plate ^-fg- 4, E, F is reprefented this nut, hufk, or fliell, in
which are two of thefe coffee beans, divided by a membrane, or par-
tition : for, that which at firft fight appears as a fingle feed, does in
fail confift of two diftin(^l beans or feeds, lying in regular order
befide each other, juft as we obferve two kernels in an almond, a
filbert, or an apricot.
In Z^-. 5, G H, is (hewn the nut or fhell, opened on one fide, fliew-
ing how the two beans lie with their flat fides next each other ; G,
is that part which was joined to the plant, and from \\ hence the feed
derived its nourifliment, and H, is the end where the young plant is
formed in the feed: fg. 6,1 K, is a coffee-bean lying with its flat
fide upwards.
I cut a flice from one of thefe beans, at the end marked I, and
caufed a figure of it to be drawn, fomewhat magnified, only to fliew
the place where the young plant lies.
Fig. 7, L M N, is this flice, and at O is to be feen the part of the
( 1^-2 )
bean where the young plant is formed ; and here that part which
would have grown up into a ftalk or fleni, is cut tranfverrely.
I liave alio laid coffee beans for fome time in water, in order more
eafily to take out the young plant, and to give a drawing of it
from the microfcope. This young plant, fo magnified, is fliewn in
Plate V. /^. 8. P O R S T V. At O R S T V are three compleatly
formed leaves, and I could fee the vellels and globules whereof they
confifted very di(lin6lly in fome of them, efpccially where the leaves
did not lie two or three together. A few of thefe globules, com-
pofing the leaf, are reprefentcd in this figure, at letter T. That
part where the root and Item would fhoot forth is fliewn at PQV.
After this young beginning of the plant had flood fome months
before the microfcope, I perceived that the leaves were covered with
a fort of mouldincfs. This ajjpearance ufually begins by a kind of
flalk ; from whence a globule proceeds, and out of that many more,
exhibiting together the likenefs of foliage, but the moirldinefs I am
now fpcaking of, had a very different appearance, being much more
in the fliape of flowers, as is fliewn \i\/ig. 8, at a a a a. But I have
often feen this mouldinefs, even on tiie dead bodies or parts of the
bodies of infe6ts, and alfo on the fhell of a filk-worm's egg.
Some of thefe beans I placed in a proper chymical veflel over the
fire, and obferved, that in the roafting, or burning them, a great
great quantity of oily fubftance. and alfo of watery moiflure was
expelled. The roafled beans I broke into fmall pieces, and after
jnfufing them in clear rain water, I iuffered the water to evaporate,
after pouring it off from the grofl'er parts of the coffee, and then I
difcovered a great number of oblong faline particles of different fizes,
(but mofl of them exceedingly minute ) all of them with fharp points
at the ends, and tliick in the middle.
Afterwards, I took fome of the coffee beans in the fame flate they
( 123 )
are imported to us, and upon fqueezing, or prefTing them with
great force, a larger quantity of the oil was exprelled than
could be imagined, and I oblerved that this oil was very clear and
tliin.
I alfo cut coffee beans into very fmall fraginents, or pieces,
in every diredlion, and I always found them to be of a very open
and fpongy texture : for, whereas, almoft all feeds confill of a
farinaceous, or mealy fubftance, (except in that part where the
young plant is contained) this feed, on the contrary, is formed
of nothing but fibres, branching or fpreading one among another,
and the cavities between them, in many places, filled with oil ; for
when I cut off very fmall pieces from the bean, I could plainly
perceive the oil, and take it out from the part where it lay.
From the middle of a bean, I cut a very fmall flice, and placed
it before the microfcope, in order to fhew the open and f])ongy
texture of this feed ; and in Plate V. fig. 9, A BC D, is reprefented
this particle, or piece of bean when magnified, the natural fize of
which was no larger than miglit be covered by two grains of fand.
The parts which in this figure appear clofed up, and fome of
them to confift of globules, were filled with oil. When a cofiee
bean is thus cut into fmall pieces, and the pieces prefTed between
the fingers, or fqueezed between any hard fubftances, the fingers,
or whatever is ufed in fuch preifure, will be much ftained with oil ;
(that is to fay, in proportion to the force applied) and I will ven-
ture to fay, that by a fingle operation of this kind, more than one
thoufand little drops of oil will be exprelled : it is here to be noted,
that the oily particles formed in the coffee bean are not perfectly
of a round figure, but in many places they lie together in iiTC-
gular fhapes.
Tiiis formation of the coffee bean being confidered. we need
( 1=1. )
no longer \voncler, that tliey cannot be reduced into powder until
they have been roafted, or burnt, for, in the roafting, much of tlic
oil is driven off and confumed by the fire, and the branchey, or
fibrous particles become weaker or more brittle, and the more
they are burnt, or roaltcd, the more eafily they can be pounded in
a mortar.
As to myfelf, who am accuftomed to take this kind of drink
every morning for breakfaft, I do not fuft'er the coffee beans to be
much burnt, and I caufe them to be pounded, or reduced into
fuch fmall particles, that they will pals through a filken fieve, and
until they feel between the fingers as fine and fmootli as flour. A
proper quantity of the coffee tlius prepared, being put into a
cofi"ee-j5ot, I pour on it boiling rain water, and then let it again
on the fire, but not to boil, and after letting it Hand for a fliort
time to fettle, this is the coffee I make ufe of.
This is not, indeed, a very profitable way of making coffee,
though much more grateful and pleafant to the palate, except to
thofe who like the burnt flavour. For, when the coffee beans are
violently roafted, they can more eafily be pounded to powder and
palled through a fieve, and the liquor clarifies fooner ; and alfo,
by reafon of the burning, the bitter tafte fpreads farther, and
produces more of the liquor, efpecially if the coffee be boiled in
the water
But, if we judge, that the oil and falts which are found in coffee,
are the parts wherein its virtue confifts, and from which we are to
expert benefit to our health, we fliall prefer that coffee which is
not over roafted, to that which is more burnt, for, in the coffee
which I drink, I always obferve a great quantity of oily particles
fwimming on the furface, which would not be found there, if the
coffee were more roafted, for in that cafe the oily particles are
more driven off by the force of the fire.
( 125 )
Many perfons fay, that coffee is not wholefome, unlefs it is made
bright and clear before it be drank ; but this, I think, is of no
confequence, becaufe I am well convince I that the particlci of
coftee, (excepting the oil and falts, which I have before mentioned
to be contained in it,) are of fo hard and inflexible a nature, that
they never can be introduced into the fyftem of our bodies.
1 have oftentimes endeavoured to bring coffee beans to a ftate
of growth and vegetation, but herein I never could fucceed : whe-
ther this was, becaufe they had been kept too long, or whether,
that at the place of tlieir growth, they had been over dried, to-
facilitate their exportation to diftant countries, whereby the juices
which Ihould iiave nouriOied the young plant were dried away,
I cannot pretend to fay.
I have feveral times placed coffee beans in a clean glafs under
water, without finding any alteration in the colour of them or of
the water, but when they were fo placed that part of them was
above the furface of the water, then both the cofFee-beans and the
water became of a grafs green colour.
I formerly thought that thefe coffee beans were produced by
fowing them annually in the manner of our peafe and beans in
Europe, but I have been lately informed by a Gentleman who has
travelled in the Eaft, that they are the feed or fruit of a tree which
grows to about the fize of our lime trees.*
* The cofFee-tree is a native of Arabia, from whence in the laft and prefent centuries
it has been cultivated both in the Eafl: and Weft Indies, but the Mocha coffee is ftill in
the greateft efttmation.
ON VINEGAR.
1 HAVE obferved, tliat on expofing a fmall quantity of white
wine Vinegar to the air for a few hours, a vaft number of corpuf-
cles, or fmall folic! fubfianccs appear in it, which I take on mvfelf
to name the falts of Vinegar. Some of thefe are reprefented in
Plate V. fig. I o ; thofe at A appeared to terminate in a Iharp
point at each end, havuig in the middle a dark fpot ; others were
glittering like cr}-Il:als, as at B, and thefe were mofl in number :
others of thefe corpufcles were of an oblong figure, and of a dark
colour, with a lucid fpot in the middle, as at C ; and fome few
of an oval form witli an oval bright fpot in the middle, as at D.
Among the figures A, B, D, I was convinced that I faw feveral
with a cavity or hollow in them, which gave them the appearance
of being iialf dark coloured, and half tranfparent. Others of thefe
falts or cryftals laid one on another in clu Iters, as at E ; and lafi:ly,
fome there were with points at one end only, like half cryfials,
as at F. It is not eal'y to defcribe the extreme minutenefs of thefe
corpufcles, and fome of thera were indeed, fo fmall that tliey
almofi efcaped the view of the microfcope.
All thefe particles, which I name the fait of vinegar, I conclude
to be thofe parts of it which excite on the tongue that tafie or
fenfe named acid. And, althougli they appeared to me, through
the microfcope, of the fliapes and fizes I have mentioned, yet
I concluded that thev were all compofcd of ftill fmallcr par-
ticles, of the fame fliape, in like manner as I have often in our
common fea-water, or in water wherein common fait is dilTolved,
when placed before a microfcope, feen many particles molt
exactly quadrilateral, or four-lquare, but lo minute that millions of
( 127 )
them were not equal to a grain of fand ; and thefe, while I contem-
plated them, would increale in iize ftill prelerving their exa6l fquare
figure. In like manner I conclude, that there are none of thefe fliarp
pointed falts which I obferve in vinegar, but are compofed of num-
bers of fmaller particles of fimilar fhape.
Having kept in my parlour for about two months, a glafs, two fin-
gers broad, with a fmall quantity of vinegar in it, expoied to the air,
I obferved, at the end of that time, numbers of faline particles fwim-
ming on the furface, and, upon more narrowly examining them, I
plainly difcerned,.what I had not fo clearly feen before, that thefe
faline particles had a kind of cavity in them, as eafily to be feen, as
if, with the naked eye we were to look into a fmall boat or a fhip,
and which, the longer the vinegar "was fulFered to fland, grew lar-
ger : fome of thefe, with the cavity in front, are reprefented at G,
and at H fome of the fame feen Tideways. I alio caufed a drawing
to be made of a living eel, of that fpecies which is often found in
vinegar, whereof the number I faw in this liquor was very great ;
this is (hewn at L M ; and at NO, another eel dead, which I killed,
on purpofe that the limnermight take it's figure more accurately.
Thefe eels (which are invifible to the naked eye) I caufed to be drawn,
that by comparing them with the before-mentioned faline particles,
the extreme ininutenefs of thofe falts might be the better conceived,
and it fhould be underflood, that by far the greater part of thefe
falts could not be difcovered by the common mlcrofcope, which
made the eels vifible. I am alfo defirous to convince thofe of their
error, who imagine, that the acid tafte of vinegar arifes from tlie
pungency, or fl.arp, fenfation, which thefe eels are fuppofed to excite
on our tongues, by their pointed tails ; for, were this the cafe, many
forts of vinegar would be taftelefs, becaufe none of the eels are to
be found in them ; and in winter time, vinegar would become vapid,
or lofe it's fournefs, becaufe thefe minute eels arc killed by cold
«sr froft.
( 128 )
I was defirous to obferxe the cffecl of crabs' eyes being iiifiifed in
vinegar, it being fiiid that they abforb or take away it-; Ibiirnefs, and
I concluded that this mull be performed by tlic acute falts before
mentioned being altered in iigure, or rendered jnore foft or flexible,
fo as to lofe their pungency on the tongue. 1 took therefore, fome
new glaflcs, and after mixing in llicni vinegar with crabs' eyes
)>roken in fmall pieces, I found, that the long pointed falts I have
before defcribed, were altered to a kind of oblong quadrilateral
figure riling in tlie middle in form of a pyramid, fimilar to a diamond
when polifhed ; thefe are rcprefented infg. ic, aj: P. others were
exactly fq,uare, as at O, and others of the fliape reprefcnted at
K. But it is to be noted, that thefe particles bore no proportion in
point of fize to the faline particles in connnon vinegar, for thefe lall
were drawn from much deeper magnifiers, without the help of
which, I could not have difcovered their fliapes. And, what I par-
ticularly wondered at was, that thefe faline particles were almoft all
of the fame fize, which I never obferved in any other fpecies of
falts. After the effervefcencc produced by the mixture of the vine-
gar and crabs' eyes was fubfided, I drank about a third part of a
thimble full of the vinegar, and found that it had no acid tafie, but
a bitternefs, fo difgufiing, as almoft to occafion a naufea or fick-
jiefs.
I have alfo pounded white chalk and mixed it with vinegar, and
1 found that it produced the fame effervefcencc as the crabs' eyes,
and the fame change of figure in the faline particles, and that it alfo
took away all the acid tafie of the vinegar.
OF THE SCORPION.
J. HE Diredors of the Eall India Company in Delft, having fent
to me a Hving Indian Scorpion, I put it into a long and wide
glafs tube, flopped at tlie ends with cork, though not quite clofe ;
and I pre fumed that, on account of the coldnefs of the glafs, the
Scorpion would place itfelf on the cork, and fo be preferved
longer alive : and I occafionally put it into a thinner glafs tube,
in order, as far as I was able, to examine it by the microfcope.
I firft made my obfervations on its legs, the fifth joint of which,
from the bodv, being very tranfparent, I there plainly perceived
the blood running in an artery towards the extremity of the foot ;
wliich artery, 1 judged to be the fize of an hair of ones head
and clofe bcfide it, tlie blood was returning in a vein of the fame
thicknefs. Thefe two veflels I deemed to be the principal blood-
veflels in that limb, and, though I was well aflured, that there were
many fmall branches through which the blood was conveyed out
of the artery into the vein, and thus the circulation was com-
pleated, yet I could not get a fight of thofe minute veflels.
The blood of this creature not being of a red colour, it may be
ranked among tliofe animals, which the antients named exfangues,
orbloodlcfs.
I faw that this Scorpion had t^^•o black eyes ; placed, not at the
extremity of the head, as we obferve in many fmall animals, by
which they difcover obje6ls on both fides of them ; but thefe two
eyes flood about tlie eighth part of an inch to\Nards the buck
R
( i^o )
part of its licad, and fceincd defigiied for the view of objcfls
upwards. And I difcovered, on eacli iide of the head, tliree other
eyes, only an eighth part tlie fize of the before mentioned ones,
placed in regular order befide each other, lb that thefe creatures
are provided with eight eyes ; and, as the two eyes on the top of
the head are only iitted to look upwards, fo, ihcfe e3es placed on
the fides are calculated to fupply the defeat of the former ones.
And herciji we fee, with how much perfe<5lion and provident fore-
fight, every creature, hovever difgufiing it may be to us, is formed
by Nature ; and th.at none of fuch creatures have ever proceeded
from corruption, as fome men have imagined, but have been
produced by their like ever fmce the Creation.
I put two living flies into the glafs with this Scorpion, in order
to fee whether it would feize them as its prey ; but they appeared
not at all frightened at the Scorpion, even fitting upon its body,
and the Scorpion was equally indifferent, and did not move itfelf
on account of tlie flies. I afterwards put a fmall lizard, newt or
eft ; and likewife a fpider and a fly at the fame time into the glafs
with the Scorpion ; but it appeared equally indifferent to them
all ; and after I had kept it by me almofl tiiree months, in which
time it had not taken any food, it died.
As foon as I perceived that the Scorpion was dead, I took a pair
of fmall forceps, and laid hold on that part in which I was per-
fuaded the poifon was depofited, and brought the fling before the
microfcope ; then, by a little comprcffion of the forceps, I caufed
the poiibnous matter to ifliie forth, which might be thought to
be emitted at the very extremity of the fting, but upon examining
the fling by the microfcope, I found that on each fide of it, near
the point, was a fmall aperture.
I have caufed a drawing to be made of this Scorpion, in order
to explain the nature of its fting.
Plate V./^-. 11, reprefents the Scorpion itfelf, and at A, is the
fting, which the animal, whether in motion or at reft, always
( 131 )
carries with its tail bent, or turned inwardii, in order, nioft pro-
bably, to preferve the fling from any injury it niiglit fuflain by
llie blunting of the point, or otherwife.
Fig. 12, F G H I, reprefents the ftijig, as feen through tlie
microfcope, and, between the letters G and H, may be feen the
aperture which the fting has, on one fide; -and j?^'-, 13, K L M N,
reprefents the other fide of the fling where tlie fame aperture is
to be obferved between the letters L M.
It mufl: here be noted, that the prominent part whicli is feen
in Jigs. 12 and 13, at letter X, is not to be taken for a fecond
fling, for in my opinion it ferves only as a bafe or fupport, to be
fixed on the fkin, in order that by its help, the fling may be thruft
in with greater force.
Upon refledling frequently on the make of this fling, I confi-
dered with myfelf, that, if the above mentioned aperture had been
at the very extremity, the fling could not fo eafily have been
made to pierce the (kin : I alfo thought, that the Scorpion has not
power to expel the poilbn, but that when the fling enters the
fiefh, then the fides of the oblong cavity in it (which is feen in
the Jigs. 12 and 13, between the letters G H and LM) are, by the
prefiure on the fling in its entrance ( in regard the inner parts of
this cavity are of a foft and yielding nature) forced inwards, and
by that means the poifon within the fling is driven out. Now,
if the Scorpion had power to eje6l its venom, I imagine that it
would not flrike at any objeft whatever with its fling, without at
the fame time emitting- fome of the venom ; but as this is not
obferved to be the cafe, we mufl conclude, that the poifon is
kept within the fling, until, by the force applied in piercing the
ficin or flefh, the poifon is driven out, and there it will exert
its full force upon the juices of the wounded part.
The liquid matter, or poifon which I before mentioned to have
extra6led from the fling by prefllire (though it was in a very
fmall quantity) I put into a clean glais, which I prepared on
( 132 )
purpofe, in order, if poflible, to difcover the faline particles
contained in it, ^vhich alone, as it feenis probable, do render this
liquid poiibnous in lb great a degree ; but, with all my attention,
I could not perceive any thing in it particularly worthy of noting.
This liquid, being in a very finall quantity, and alfo being
fpread very thin, in a Ihort time, all the moiflurc of it .was evapo-
rated, leaving a kind of thick gummy matter, mixed with various
different particles, to which I could not afTign any particular
figure. Hereupon, I, without lofs of time, made a pun6lure on my
finger with a needle, and applied a fmall portion of the blood
wiiich illued from the part, to this poifonous fubdance, in order
to fee, whether the blood would undergo an}'^ alteration by the
mixture. But, nothing of that kind appeared, for I could not
difcern any difference between the blood which was placed on
the poifon, and that which lay near it.
The next morning, I diflecfed the tail of this Scorpion, and,
from each joint, I took out two flelhy mufcles, of a very white
colour, each of which was compofed of a great number of very
fmall oblong particles, terminating at the extremity of the mulcl
where it grew fmaller, thus forming the tendon : on one of thefc
mufcles was a kind of veflel, fliaped in the middle like a bladder,
and this, I concluded, was deflined to convey the poifon to the
extremity of the tail. Thefe flelhy mufcles were furnilhed with
annular parts, or rings, ferving to extend and contra6l th.e mufcle.
Thofe eyes whio'a were fjtuated on the upper part of the head,
I placed before the microfcope, whereby I faw how perfectly the
tunica cornea, or horney coat of the eye was formed ; for through
it I could fee all the furrounding objects (though wonderfully
diminifhedj fo diftin<5fly, that I could not contemplate the fpedtacle
without admiration ; but this pleafmg fight was not of long conti-
nuance, for the tunica cornea foon dried and flirivelled up.
Upon opening the belley, I could not form any judgment of the
inteftines, by reafon that they had begun to decay, except that I
( ^33 )
found twelve eggs, each about the fize of a grain of millet, of a yel-
low colour, and in Ihape not unlike a lemon.
In tlie fore part of tlie head, and jult in front of the mouth, I
ohferved two teeth, each fixed on a fliort joint, and they are ufed,
as 1 imagine, by the Scorpion, to grind its food, before it is taken
into the mouth. Thefe I feparated from the head, and found each
to confilt of a three-fold tooth, one of which was fo made, as to fit
exa6lly the cavity between the two oppofite ones. And, to (hew
tlie llrength of thefe teeth, I caufed a drawing to be made of one
of them. Fig. 14, O P Q R, is this tooth, or more properly this
three fold tooth, and on it, at P, are to be feen fome huirs; the legs
of this creature are alfo covered with hairs.
I alfo placed before the microfcope one of the claws, which are
like thofe of crabs or lobllers, and in Jig. 11, are to be feen at C
or D. And I caufed a drawing of this claw to be made, in order to
fhev/ the curious formation of it. Fig. 15, S T, is the claw, magni-
fied, and on it are plainly to be feen a great number of teeth or
notches, like thofe of a faw, Ibme of them larger than others, and
which faw-like teeth, I doubt not are fo formed for enabling th,e
Scorpion firmly to hold liich fmall living creatures as it catches for
its prev.
Seeing now, the wonderful make of this animal, thougli to us
it is fo detefiiHe, and indeed fo noxious ; and, confidering the perfeft
wifdom requifite for the contrivance of its feveral parts, we have
furely ten thoufand times more reafon to believe that its origin is
derived from thofe which were created at the Beginning, tlian to
adhere to the chimasras and errors of the ancients, fome of whom
have tranfmitted to us in tlieir writings, the notion, that Scorpions
are not produced by generation, but from the great heat of the fun ;
others, that they are bred from putrefa6tion in the bodies of croco-
diles ; and others again, that they are generated in rotten wood, and
fuch like fidtions.
( i34< )
ADDITION, BY THE TRANSLATOR.
Ir may not be unacceptable to the Reader, to fubjoin a quotation from
Dr. Mead's celebrated EfTay on Poifons, and the rather, as the fentiments of our
Author, in regard to the nature of the Scorpion's polfon, are exadlly fimilar to
thofe of the Uoiftor's, when treating of that emitted from the Viper's fangs ;
which animal, being much larger than the Scorpion, might afford Dr. Mead a
better opportunity of inveftigating the nature of this fubflance, than Mr. Leeu-
wenhoek could have, in the very fmall quantity which he collefled from the
Scorpion's fting : and, as we fee that the operations of Nature are performed
with the greatell uniformity in cafes which are analogous, it may fairly be
concluded, that what Dr. Mead' has faid, refpeding the Viper's venom, may be
applied to that of the Scorpion, and of more minute noxious animals.
Dr. Mead expreffes himfelf on this fubjedl, in the following words :
* This venomous juice itfelf is of fo inconfiderable a quantity, that it is no
' more than one good drop that does the execution. And for this reafon,
' authors have contented themfelves with trials of the bite upon feveral animals,
* never eflaying to examine the texture and make of the liquor itfelf; for
' which purpofe, I have oftentimes, by holding a Viper advantageoufly, and
' enraging it till it ftruck out its teeth, made it bite upon fomewhat folid, fo as
* to void its poifon ; which, carefully putting upon a glafs plate, I have with a
' microfcope, as nicely as I could, viewed its parts and compofition.
* Upon the firfl: fight, I could difcover nothing, but a parcel of fmall falts
* nimbly floating in the liquor ; but in a very fhort time, the appearance was
' changed, and thefe faline particles were now fhot out, as it were, mto cryftals
* of an incredible tenuity and fharpnefs, with fomething like knots here and
' there, from which they feemed to proceed : (o that the whole texture did in
' a manner reprefent a fpider's web, though infinitely finer, and more minute ;
* and yet withal, fo rigid where thefe pellucid fpicula, or darts, that they remain-
* ed unaltered upon my glafs for feveral months.*
* I have tried feveral ways to find out, if 1 could, under what tribe of falts
* thefe cryftals are to be ranged, and to difcover what alterations they make in
• A reprefentation of this, taken from Dr. Mead's work, is given in Plate V./^. i6.
( ^35 )
* the bfood : and, mt without T'lme difficulty, by reafon of the minute quantity
' of the liquor, and the hazard of experiments of this kind, fome curious friends,
* and myfelf together, made the following obfervations ;
* ABout naif an ounce of human blood received into a warm glafs, in which
* w.rs five or fix grains of the viperine poifon newly ej vTred, was not vifibly
' alrcied either in colour or confiftence : it then was, and remained undiftin-
' guilTiable from the fame blood, taken into another glafs in which was no
' poifon at all.
' Thefe portions of blood were feverally mixed with acids and alkalis : the
* empoifoned blood was, aner fuch mixtures, of the fame colour and confift-
* ence as the other.
' Spirit of nitre, fpiiit of fait, and juice of lemons, feverallv poured upon
' the fanies itfelf, produced neither fermentation, nor any change of colour.
* Salt of tartar run per deliquium, and the fimple fpirit of harrtiorn, dropped
' upon the venoin, neither altered its colour, nor raifed any ebullition.
' Syrup of violets mixed with the poifon did not change its colour either to
* red or green.
* The tinfture of heliotropium, that is, blue paper, was not altered by the
* fanies ejeded upon it; and this, drying, ftill retained its yellowifh colour.
' We caufed feveral animals, dogs, cats and pigeons, to be bit by an enraged
* Viper ; which generally died, fome in a longer, others in a fhorter fpace of
* time. But we conftantly obferved, that they all, immediately upon the bite,
' (hewed with figns of acute pain, marks of their life being affeded, by
' fickncfs, faintings, convulfions, &c.
' The head of a large Viper lay three hours after it was cut off; it was per-
* fedly flaccid and without motion. A pigeon, wounded upon the breaft with
' the fangs cf this head, was prefently convulfed, &c. as from the bite of the
* animal, and died in feven hours.
' We contrived a fharp fteel needle to be made, crooked, in fhape not un-
* like to the Viper's tooth, with a fulcus or hollow on the convex part, not far
* from the point : into this, we put a drop of the venom, and with it wounded
' the nofe of a young dog. It produced the ufual diforders of vomiting, purg-
' ing, &c. but in a Jefs degree, and the dog recovered. It was remarkable,
' that upon making the wound the dog cried but little, till the poifon came
' into it; but then he howled, &c. in the fame manner as if bit by the viper
* itfelf. But a pigeon pricked in the flelhy part of the breaft, by the fame
' poifoned needle, fuffercd as from the bite, and died in about eight hours.
t
( 136 )
* "We refolved to end out poifon-inquiries by tafting the venomous liquor.
* Accordingly, having diluted a quantity of it with a very little warm water,
' feveral of us ventured to put feme of it upon the tip of our tongues. We all
' agreed, that it tafted very (harp and fiery, as if the tongue had been ftruck
* through with fomething fcalding or burning. This fenfation went not off in
* two or three hours, and one gentleman, who would not be fatisfied without
* trying a large drop undiluted, found his tongue fwelled, with a little inflam-
* mation, and the forenefs lafted two days ; but neither his, nor our boldnefs,
was attended with any ill confequence.
• This is no obje<5tion to the hurtful quality of this juice: for, as fome chy-
* mical liquors ferment with others of a certain kind only, fo thefe poifonous
' fatts may affeft one fluid of the body, and not another ; it is fufficient to the
* prcfent purpofe to fay, that the faline fpicula arc broken and dilTolved in the
* mouth by the clammy falival humour : and if any of them (hould pafs thence
' into the (lomach and inteftines, the balfam of the bile will be an antidote
^ there, powerful enough to overcome their force.
* Thefe experiments upon the Viper poifon and the blood, are a fufficient
' confirmation, that the nervous liquor only is afFeded by this venom ; and at
' the fame time afford a convincing proof, how much thofe fcanty principles of
* our chymifts, acid and alkali, fall (hort in explaining the anions of natural
' bodies.j fince neither of thefe falts could in any way be found to affcd the
* viperins venom.'
Mechanical Account of Poifons, p. 14, & feq. Ed. 1747.
The Doiftor's Eflay on the Nervous Fluid and the manner in which it is
affefled by animal poifons, is too long to infert in this place, but the Reader
will find it in the Introdudlion to the work from which the preceding paflage is
taken ; that is to fay, in the later editions, for it is not to be found in the firft,
printed 1702.
Of the Oak gall, or Gall-nut;* that it is not a fruit, but an excrefcence
produced on the leaves of the oak, by means of an infeSl ; the manner
of its formation particularly defcribed. Afmiilar excrefcence produced
in like jnanner on the T/iiJile.
VV HILE I was employed in the fummer feafon, to colleft
acorns from the oak, in order to examine the beginning plant in
that feed, I faw with furprize, that the gall-nuts were produced
upon the leaves of the trees. This feemed the more extraordi-
nary, becaufe I had fuppofed that they were the fruit of the tree,
but now I found that' they were occafionally, or accidently pro-
duced on the leaves of the oak. I was convinced of this, partly,
becaufe I faw but a few leaves here and there with gall-nuts on
them, (in fome of which I found four, five, and even fix galls)
and in others I could not find a fingle one ; and in the next
place, becaufe I faw, that thefe galls were formed upon the large
fibres, or vellels in the leaves, which were burll or broken, in
the places where the galls were formed ; fo that I concluded that
fome infe6l had wounded or gnawed thofe vefiTels, and that the
juices of the tree, flowing out of the wounded part, had extended
themfelves in globules and vefTels, and thus, at length caufed the
formation of the gall-nut.
* This is a literal tranflation of the Dutch word Gahoot, ufed by the Author; in the
Latin tranflation it is Galla, which Ainfworth renders ' a fruit called gall, or oak-apple;'
but this is a miftake, for the oak-apple is not the gall, nor is it formed on the leaves of the
tree, but at the ends of the fmall twigs ; and it is produced, not by a fingle infe(ft, but by
a great number colleded together, and thofe of a different fpecies from the infedl found
in the gall-nut.
s
( 138 ;
On my return home, I examined thefe gall-nuts more accurately,
and found tliat each of them had a cavity in the middle, wherein
lay a living white worm, which had very little motion : it was
thick, in proportion to its length, and lay bent m a circular form,
the body of it confifting of thirteen or fourteen rings, as we fee
fdk-worms and caterpillars, and thefe covered with pointed hairs.
It feemed to me worthy of obfervation, that, from this
time, I obferved thefe worms, or maggots, continue alive to the
end of December ; and that, in gall-nuts which I had gathered in
the fummer, and which were fo dried, that I thought they were
Ihrunk to half their former fize ; whereupon I concluded that the
worms, for want of fufficient nourifliment, had not arrived at their
full growth, fo as to be changed into flies, and had only been
fupplied with food fufficient to keep them alive. But, wiien they
had grown to be fomewhat larger than a great pin's head, then
I faw the eyes beginning to be formed, wliich were of a black colour.
After this, I went occafionally into the wood at the Hague, in
order to purfue my fpcculations, and obferved that thelc worms
were changing into flies ; for, I not only could fee their eyes per-
fe6lly formed, but I alfo could difcern plainly their horns and
feet, and the hind part of their bodies. Tliis infeft then lay with-
out any motion tliat I could perceive, with its feet, fix in number,
and its two horns lying in regular order clofe to its body, in like
manner as we fee in the aurelia of the filk worm, before it comes
out of its fliell, or covering, but in this animalcule I did not
then obfcrve any fuch cafe or covering ; but only the fliape of a
fmall fly without wings, the hind part of its body of a round form
and of a fliining black colour, and which in a fliort time was
provided with two larger and two fmaller wings ; and I after-
wards found that thefe aurelias had a thin covering, \\ hich enclofed
the body, but not the feet.
From thefe my obfervations, I concluded, that tlicfe animalcules
( 139 )
were thus produced, namely, by the before-mentioned kind of
fl\, laying its eggs on the leaves of the oak, where, when the
young maggot is hatched, it bites or pierces the vellels of the leaf,
fo that the juices flow out, and are hardened into globules, fpread-
ing themfelves, at the fame time, in a circular form like veffels,.
and thus produce what is called the gall-nut, and which juices, while
hardening, do inclofe the maggot in the middle.
This newly-formed gall-nut fupplies the animal with food,
for it eats away the fubftance of the nut by little and little, round
about itfelf, whence proceeds the cavity we find in the middle of
thefe galls, and which cavity grows larger, as the animal increafes
in fize. And it feems to me, that unlefs fome of the large vellels
in the leaves were injured or perforated by one of the maggots
I have defcribed, there could not be any gall-nut formed, for in
every nut which I opened, I conftantly found a maggot (though
in an hundred fuch nuts, I found but two which contained more
than one) and this, though one gall-nut was fixty times the fize
of another,
It is however to be noted, that the wounding or biting the
large veflels in the leaves, does not conftantly produce a gall-
nut ; for this is only formed, where a fufficient quantity of the
juices ifl'ues from the opened veflels ; to this alfo, the heat contri-
butes much, by condenfmg or thickening the juice ; and hereupon
it is my opinion, that where thefe veflels are opened in the morn-
ing, galls will more eafily be formed than when it happens in the
evening , for I law on thofe leaves on which were gall-nuts, and
alfo on thofe where none were to be feen, the leaves and veflels
much eaten into, and the veflels pierced through, and yet, not the
leaft appearance of the formation of a nut on the place. Farther,
I concluded, that many of thefe maggots get their fulienance
from the leaves without piercing the large veflels, for in many
places I faw the leaves eaten av/ay and in holes.
In further profecuting my inquiries on this fubje61;, I found
( HO )
that the beft fort of gall-nuts which are ufed in this country, are
brought from Aleppo. Hereupon I confulted Tavernier's Tra-
vels, to fee what he fays on this fubjc(5l ; and I found, that in his
third book, when fpeaking of his journey to Aleppo, he fays, ' the
* hills are covered with oaks bearing the gall-nut, and fome
• of them, befides gall-nuts, alfo produce acorns.' But, after
the preceedijig obfervations, we are not to wonder, that the fame
oak will produce both galls and acorns, fince nothing more is
wanting for the produ6tion of a gall-nut, than fuch a fly as 1 have
mentioned, from the eggs of which, worms fhall proceed, which
feed upon the leaves of the oak.
To fatisfy myfelf more fully in this particular, I examined
feveral of thofe gall-nuts which are imported to us, and are much
ufed by dyers ; and in fome of them I found a dead fly, of the
fame fhape with thofe found in the galls of this country, and in
others, only a cavity in the middle, with a round hole reaching
from that cavity to the furface of the nut, and in the cavity a kind
of dull, which I imagined to have been the excrements of the
worm while it was in the nut, And I found upon farther profe-
cuting my obfervations on the galls which I gathered from the
trees here, that not only the maggot is able to gnaw the fubltance
of the nut ; but alfo, that the fly has power to perforate it, to open
a paflage for itfelf though I do not think that the fly ufcs the fub-
ftance of the nut for food.
In others of thcfe Aleppo galls, I faw no appearance of any
hving creature having been inclofed ; tlie reafon of v.hich I
concluded to be, firft, the maggot in our gall-nut, even when of
its perfecft fize, is very tender, and cruflied with the leaft touch,
and contains nothing in it, but a whitifh fluid fubftance, fo that if
a maggot happens to die in the nut, whether from the juices
being too acrid, or the nut too hard, in fuch cafe, the ful)ftance
of the worm may fo drv awav, as to leave no traces beliind it.
In the next place, a maggot, when grown to a confidcrable fize.
( H.1 )
may pierce a large vefTel in the leaf, and afterwards fliift itfelf to
another place, and out of the large vefl'cl fo wounded, a gall-nut
may be produced without any maggot in it. The gall-nuts
which are formed without any infeifts in them, are generall}' the
heavieft, by reafon that they have not any cavity made in their
infides.
With regard to my preceding obfervations on this fpecies of
fly, I was the more confirmed in my opinion, upon recoile6liou
of what I have obferved of the like kind in divers trees, and par-
ticularly the willow ; on the leaves of which I have feen certain
green tubercles or fwellings, on opening which I have found
animalcules within them, fome of which were alive, and others
dead ; all which I doubted not were produced by maggots hatched
from the eggs of the flies of the fame fpecies as thofe which
I had found in fuch tumours or fwellings. For it is. with me an
eftabliOied principle, that no living animal, whether worm, fly,
gnat, or mite, can be produced from the mere juice or leaf of any
tree or plant, nor from corrupted or decayed fubftances.
I have caufed a drawing to be made of thefe galls, as they grow
or are produced on the leaves ; and in Plate V. fg. 17, A B C D,
is reprefented an oak leaf, with that fide upwards, which, when on
the tree is undermofi: ; for I never faw any of thefe galls on the
upper fide of the leaf ; the reafon of \\ hich I take to be, that if
the maggot was placed on the upper fide, and expofed to the fun's
heat but for a fhort time, it would, by reafon of its fmallnefs, be
dried up and perilh. On this leaf are feen two large galls, and
two fmaller ones, at the letters E, F, G, H.
Fig. ]8, 18, exhibit a gall-nut cut in half, wherein, at N, N,
appears the cavity, in which the maggot lay ; fome of thefe
maggots, of different fizes, are fliewnat I, K, L M.
Fig. 19, fliews one half of a gall-nut, with the fly in it, which has
opened to itfelf a pafi'age from the cavity as far as the furface of
the nut, and at fg. co, is the other half, exiiibiting the cavity in
( 142 )
tlie center, formed by the maggot, and the perforation to the cir-
cumference made by the fly.
Fig. 21, is the fly bred in this gall-nut, \vhofe body is not quite
fo large as reprefented in this figure, but the wings are of the
fame fize as they appear liere.
After thcfe obfervations, in the month of January, I again went
in fearch of gall-nuts, upon the leaves of the young oaks, and
thofe which hung near the ground ; and I found a great number
of them, although the leaves were very much dried ; in many of
thefe galls I faw the perforation through ^\hich the fly had ifllied ;
in others of them I found living flics ; and in others, living mag-
gots.
Some of thefe galls I placed in my clofet, and opened them at
different intervals of time, and I always found either the maggot
in them alive, or a hole, tiirough which the fly had ifliied : ten
of thefe I kept till the end of April, and upon opening them, I
found them all perforated with holes, and the flies which had
iflued fi-om them, lying dead.
While I am on this fubjeft, I can not forbear to mention, tliat
in the autumn there were brought to me a parcel of roundifli
fubflances, which were gathered from thiftles, and therefore,
called thiftle-nuts. Many of our countrymen carry tliefe nuts
in their pockets, under a notion that while they wear them, they
fliall be free from the diforder called the piles, particularly if every
year, they throw a\\ay the old nuts and procure frefli ones (which,
it is faid, do not grow in our province). And fome fay, that there
is a maggot in thefe nuts, and that while it lives, the before men-
tioned virtue remains in the nut, but upon its dying the virtue is
loft.
As foon as I faw thefe fuppofed nuts, I concluded that they
were produced, as I might fay, by accident ; and that their virtue
againft the piles was a mere imagination. And upon examining the
nuts, I found that there was not one of them which had not one,
( H3 )
two, three, four, and fome as many as fcven or eight cavities
in it, each cavity containing a fhort, white aurclia, or chryfahs,
formed of many joints like rings; thefe aurehas were ahnofl: all
alive, and I judged tliem to have been produced from maggots,
tlie offspring of fome fly or iuch like infect, which had laid its
egg on the thiftle ; and that thofe maggots having pierced the
vcllels of the thiftle, while in the flourifliing time of its growth,
had occafioned a copious effufion of juices, by means of which a
tumor or fwelling had been formed upon the tliillle, which had
inclofed the maggot, and formed a folid fubftance round it. And
upon further profecuting this fubjedl, to elucidate my own pofi-
tion that thefe nuts had been produced by means of maggots, I
opened feveral of them at different times in the fucceeding winter,
preferving the aurelias ; and at length, towards the end of the
April following, they produced a fpecies of black flies, different
from any I had before fcen, for the hind part of their bodies ter-
minated in a point, forming a kind of fheath, wherein was con-
tained a fmall fling.
I thought it would not be amifs, to exhibit to the view, the
fliapc and make of thefe nuts, in order to fliew tlic fizes of thein
and of tlie cavities they contain ; and alfo how -far, fancy and
imagination will go with fome people.
Plate V. fg. 22, 23, 24, reprefent three of thefe thiftle-nuts
dried, and of different flzes.
Fig. 25, is one of the fame nuts, cut open on the fide, where
may be ^een two cavities, one of them, at A, containing an aurelia.
Fig. 26, is the fly produced from this aurelia.
Fig. 27, is a tliiftle-nut cutacrofs, fliev>ing feven ca\itics, wherein
the aurelia had Iain,
END OF THE FIRST PART.
INTRODT^CTION to the SECOXD PART.
/\S I have entitled this Tranflation, Tiie difcoveries of the Author
in m -.ny of tlie Works of Nature, 'a tenn ufed by himfelf) I fhall
take the hberty to lay before the Redder a few words, rerpe6ting the
idea we ought to annex to that expreffion.
By the word Nature, hereufeJ, I underftand that unfeen power
whereby diiferent parts of Matter are brought together, and, by
their various combinations and modifications, produce thofe bodies or
fubftances which we obferve on this terraqueous globe. Matter, is
.that Somethmg, of which Bjdies are compofed, and ' call it Some-
thing, becaufe it. primary or original particles are lb minute as to be
entirely und'.Lernible by us ; and it is not until they are combined or
colledled in larger portions that they become objedts of our fenfes.
This is capable of demonflration many ways: for example. Earth,
which, in itfjlf, has littb either of tafte or fmell, produces herbs,
fljwers, and fraits, poU'eding an fendlefs variety of taftes and odours;
and not only fo, but of natures entirely different from each other, the
fame fpot of earth which produces wholefome herbs for our tables,
bringing fortn alfo the mod noxious plants, according to the qua-
lity of the feed or plant cjmmitted to it : and yet, we cannot trace
thefe various tades and odours, nor thefe wholefome and noxious
properties, in plants, to any other original than the fame common
parent Earth, aided by fuch fupplies as they receive from the other
*elements. Herbs, taken into the flomachs of animals, are converted
* Water, it is well known, is cfTential to the growih of plants, neither will they vrgetate
without a fupply of Air, a fluid eight hundred ti;r.ts lighter than water; and, it is the opinion
of tjir Ifaac Newton, that L'ght, whicli is beyond all cor.ception more rare and fubtile than air,
does enter iiUo the compofition of Bodies.
a
(;
into tlie fleHiy parts uf their bodies, and even compofe tlie Tolid fub-
{tances of the bones and teetli : and all thcfe vegetable and animal
fal)!hinces do, by putrefaction, return to the general mafs of Matter
from which they were firft formed, and enter into the compofitionof
new Bodies. Again, water evaporates, or is carried up into the al-
jnofpijerc, in particles fo fmail a.s to be invifible to us ; and even mer-
cury or quicklilver, theheaviefi of all fluids, upon the application ofa
moderate degree of heat, flies olFin vapour, and. unlefs confiiicd by
fome i'jlid body, fuch as a c!ie nift's retort, wholly d fuppeans. Ar-
guing then, from thefe appearances, we mu i conclude, that the
elementary or original particles of Matter, are not, as fuch, difcovcra-
ble by us And, as far as ocular e aniination can reach, Mr. Leeuwen-
hoek has given it as his opinion, that, had he been able, by the help of
glades, to have difcerncd objcdls, millions cf times fmal'.er than thcfe
Jiis microfcopes difcovered, he could not have traced Bodies to their
original component particles.
Some Philofuphers have fpent much time in arguing on th.e infinite
divifibility of Matter, and in propt>fing ftiange * thecries refpedting
its inherent properties. But liere'n, they I'eem to have exercifed their
wits, without much improving their undjrfland'Ugs; f( r furely, it is
of no utility to propound queftions, which cai.not poi^'bly be brought
to the tefl of e.Kperiment. In oppofition to thcfe vain fpecula'^ions,
how wife, and, at the fame time, how modeft, are the words of Sir
Ifaac Newton : -j^ " U feems probable to me, that God in tl e Ee-
" ginning, formed Matter, infolid, mally, hard, impenetrable, move-
" able particles, of fuch fizes and figures, and with fuch other proper-
" ties, and in fuch proportion to Space, asmoft conduced to the end for
* Such as that of fuppofiiig the cohcfion of bodies to be caufeJ by their particles being
formed with little hooks; and, that rcpulfi. n proceeils from other particles being made like
hoops rolled up, and afterwar s expanding themfelvcs.
f Newton's Opticks, Qii. 31, near the end.
Ill
" n-!i;c'i -le '"o-^Ti-^'' t.'ir^m ; aivl t'l.it thifj pri-nirive particles bein;^
" boil, « -i.-j irc'j iiparably ha-djr t'nan anv p.rous bodies coinpoua iei
" of tlum, e- e ; i"o very lia d as never to wear or break in pieces ;
" no ordiiiai ■' power being able to divide, whit God himfe f made one
" in thefirft Crcatio i. While the particles continue entire, they may
" compole Bodies v.f one and the fame nature and texture in all aj^es ;
" but, IhouiJ they wear away or break in peices, the nature of things
" depending on them would be changed. Water and Earth, com-
" pofed of (;ld worn particles, and fragments of particles, woald not
'• be oi" the lame nature and texture nov/, with water and earth com-
" pofed of entire particles in the Beginning. And therefore, that
" Nature may be lading, the changes of corporeal things are to be
" ])laced only in the various feparations and new ailbciations and mo-
" tion-; of thefe permanent particles ; cotnpound bodies being apt to
" break, not in the midll: of folid particles, but where thof'e particles
" are laid together, and only touch in a few points." This feems to
be th^ ne plus ultra, or utmoii extent of human fagacity, terminating
in a conclulion, worthy of that great Philofopher and good Man. In
conformity to which, I think we may fay, that the particles of Matter
are n^t infinitely, but indefinitely fmall, or, in other words, \^o
minute as to be fingly, invifible to us, though collectively, they are
the daily objects of our fenfes. It now remains to confider the pro-
perties of Matter, or, the means by which its particles are brought
into action.
The Honourable Mr. Boyle has written an Efi'av on this fubjeft,
wherein he refutes the error of the ancient heathen Fhilofophers, and
tlieir followers among the moderns, the Schoolmen, who figured to
tliemfeives, an aflive, intelligent Being, which they ca:led Nature ;
fubordinate indeed to the Deity, but yet, prefiding over the mundane
Sytlem, and direc^ting its operations. He Ihews, in a variety of
inltances, that the fuppofition of fucli a Being, is iiifutlicient to lolve
a 2
IV
tlie different pha^nomena in thefyfiem, and, tliat it de^^radls fromtbe
honour of the Autlior and Governor of the World : And he gives us
liis opinion on the fubje6l, in thefe words : * '• Since the prefent is a
" philolbphical enquiry only, we (hall only, at prefent, confult the
" light of reafon in the formation of tlie World, which might proba-
" bly bs after the following manner. The great and wife Author of
" things, lirft forming the univerfal undiftinguiflicd Matter, put its
" leveral parts into various motions, by wiiich they muli needs be di-
" vldcdinto innumerous particles of different bulks, figures, and fitu-
" ations ; guiding and over-ruling the motions of thoie parts, by his
'• wifdom and power, fo as to difpofe them into that beautiful and
'• orderly frame we call the World ; fome being fo contrived, as to
" form feeds, or the feminal principles of Plants and Animals. Be-
'• fides, he fettled fuch laws or rules of local motion, amongft the parts
" of Matter, that, by his ordinary concourfc, the parts of tlie Univerfe
" oncecompleated, fhouldcontinuetheoeconomy of the Univerfe, and
" propagate the fpecies of living creatures." And again, he lays,
" If we fuppofe the univerfal laws of motion to be ellabliflied, and
" that, by their conventions, the feminal principles of various things
" were contrived, by the local motion of Matter, Ikilfully guided at the
" beginning, and that God's ordinary and general concourfe, contri-
" buted to perfe6l the Univerfe, and continue it fo, there is no need of
'•' any diflinc^l powerful intelligent Being to aflill him, as Nature is
" reprefented ; fincethe Phtenomena wliich occur, will flow from the
" mere fabrick and conflitution of the World. "
The learned Dr. Mead has a paffage on this fubjeft of Nature,
when £fj-)plied to animated bodies, which I the rather quote, as it con-
tains a reproof to thofe vifionary Philofophers I have mentioned.
•f- " Whereas the Word Nature, is made ufe of by Phyficians, in
* Enquiry into the received noton of Nature,
t Mead on the Small Pox, Chap. II.
V
" tlie cure of all difeales, I will here, once for all, plainly declare my
" fentiments of what we ought to underlland by that word. That
" there is fomctliing within us, whicli perceives, thinks, and reafcns,
" is manifeft beyond contradi61:ion : And yet, tlie nature of that
" fomething, cannot be fully and perfe6lly comprehended in this life.
" Wherefore I Ihall refign the difquifition of this point to thofe, vho,
" while they know too little of, and care lefs for, things falling under
" their fenfes, take great pleafure in inveftigating tiioie things which
" human reafon is incapable of conceiving. However, thus far the
" foundell Philofophers agree concerning it, that it is fomewhat in-
" corporeal. For, how can fluggifli Matter, which is, of itfelf, void
" of all motion, be the fource and firft caufe of Thought, the moft
" excellent of all motions .? Wherefore, it is fufticiently evident,
" that this firfi: mover within us, is a fpirit of fome kind or other,
" entirely different and feparable from terrefirial matter, and yet,
" moft intimately united with our body. "
" Moreover, to me, it feems probable, that this active principle, is
" not of the fame fort in all ; that the Almighty Creator has en-
" dewed man with one fort, and brutes with another ; that the for-
" mer fo far partakes of a divine nature, as to be able to exift, and
" think, after its feparation from the body ; but that OTc latter is of
" fuch an inferior order, as to perifh with the body. "
" Now this matter, if I am not miftaken, {lands thus : Such is the
" compofition of our fabrick, that when any thing pernicious has got
" footing within the body, the governing mind gives fuch an impulfe
" to thofe inftruments ^of motion, the animal fpirits, as to raife
" thole commotions in the blood and humours, wh.ich may relieve
" the whole frame from the danger in which it is involved. And
" this is done in fo fudden a manner, that it Ihould feem to be the
" effe6l of inftin6l, rather than voluntary motion, thougli it be
" effe6led at the command of the aftive principle. And, indeed, thofe
VI
" \cry motions, wliicli are cominonlv caTcd natural and vita!, as
" tlioie cf the heart, lu. gs, and intellines, which perfevere thioi'gh
" the whole courfe of life, even when rhe wih cannot be coi leintd
" in them, as they have their beginning from the mind, fo they are
*' I'erpetUiilly under its dirtiiion. "
Sir Ifaac Newton, in that part of his works above quoted, ex-
preflles himfelf as follows : " All material things feem to have been
" compoied of the hard and folid particles above menticntd, var'oufly
•' ailociated in the firit Creation, by thecounfel of an intelligent Agent.
" For, it became him who created them, to fet them in order. And,
" if he did fo, it is unphilofopliical to feek for any other origin of the
«' NN'orid, or to j^etend, that it might ariie out cf a chaos, by tiie
" mere laws of Nature ; though, being once formed, it may continue
" by thole laws, for many ages. For, while Comets move in very
" eccentrick orbs, in all manner of pofiticns, blind Fate could never
*' make all the Planets move one and the fame way, in crbs ccnccn-
" trick, fonie inconfideruble irregularities excepted, which may ha\e
" arifen from tlie mutual ac^lions of Comets ai;:d Planets upcn ci e
" another, and which will be apt to increafe, till this Syftem wants
" a reformation. Such a wonderful uniformity in the Planetary
" Syilem, muft be allowed the cfiec^l: of choice. And fo mufl the
'• uniformity in th.e bodies of animals they having gcnenilh% a right
" and a left fide, Ihaped ahke, and, on either Tide of their bodies, two
" legs behind, and either two arms, or two legs, or two wings before
" upon their Ihoulders ; and, between their thouldcrs, a neck run-
" ning down into a back bone, and a head upon it; and, in the head,
" two ears, two eyes, a nofe, a mouth and a tongue, alike fituated.
" AHb, the firft contrivance of thofe very artificial parts of animals,
" the e\es, ears, brain, mufcles, heart, lurgs, midriff, glands, lar\nx,
" hands, wings, fwimming bladders, natural fpecSlacles, and ctler
" organs of fenfe and motion, and tlie inftin6> of brutes and infcdts.
vn
" can be the cftccfc of notliing elfe, than the wifdom and rKillofa
" powerful ever-living ■-\gent, who, being in ali places, is mo e able,
" by his will, to move the bodies within his boundlefs uniform
" *Senforium, and thereby to form and reform the parts of the Un.i-
" verfe, than we are, by our will, to move tlie parts of our own
" bodies. "
I hope I may be permitted to add to tlie opinions of thefe great
men, an obfervation, which, 1 think, mufl have occurred to them,
thougli they have not particularly mentioned it, except Sir Ifaac
Newton, in the laft lines of the pad'age I have quoted from him- The
laws of motion which, according to iMr. Byyle, were eflabliflied at
the Beginning, and afterwards, continued, by wliat he calls, " the
" ordinary concourfe of the Creator, " and which principles are ftiied
by Sir Ifaac Newton, " the laws of Nature," cannot have any force
without the fame exertion of power to fupport them, by which they
were at firfl created. Nor can the incorporeal mind or fpirit. menti-
oned by Dr. Mead, preferve its activity without the continued influ-
ence of the Supreme Mind. For, the cafe is not analogous to what
may be fuppofed of a workman, conftru6ting a machine, which fliall
for a length of time continue in motion, without his intervention ;
nor to that of a mafter, giving directions to his fervants to perform,
what they afterwards accompli Hi of themfelves. For, in the cne
inftance, the machine, if its firfl mover be a weight, is kept gcing
by the law of gravity, and, if a fpring, by the power of elafticity,
both which are entirely independent of the workman ; and, in the
other inllance, the fervant executes his mafter's commands by vir-
tue of the powers of felf volition and action he podefles, independent
of that mafter, though, for the time, he willingly applies thofe powers
to the accomplhbment of the talk aftigned to him. But, v>e cannot
* Senforium, menus tlie fcnt of confcioufnefs or perception, in animated Beings ; and, vvhsn
applied to the Deity, his Omniprefence makes it to be every part of Space.
vin
conceive nny a(5live principle to exifl, in either Matter or Spirit, with-
out the fiipport of iheiirft Caufe ; for this would be to fuppofe more
thnn one adlive indenenaent Exiftence, wiiich Ur. Clarke has proved
to be the 2: eateft abfurdity * Upon the whole, when we invefligatc
this lubjtdt as far as our faculties will extend, we cannot do otherwife
than refolve all, that we call the operations of Nature, into the con-
tin al trencv of the fiift Creator. And, thouo[h we are lolt in the
idea of fuch imnienfe and inccdant energy, we are equally fo, in the
contemplation of any other of the Divine Attributes, forafmuch as
finite capacities cannot comprehend Infinitude.
While we poilefs thei'e fentiments, and keep the idea of Nature,
and the Author of Nature, conne6led, (which it is not eafy for a
reHe6ting mind to feparate) I cannot, for my part, but approve the
•f peifonifying 'gure, which I think more decorous than to name the
Deity on every trivial occafion: and Mr. Lceuwenhoek feems to
have bjen of this opinion, for he frequently ufes the expreflion
" de voorfichtig Natuur" /. e. provident Nature, but when the won-
ders he dilcovers excite his admiration, that admiration is always
diredled to the Creator.
* Clarke's Demonftratlon of the Being and Attributes of God.
t The Ancients pictured Nature in a female form, to denote her fruitfulnefs ; and, with
many breads, to typify the abundant provifion made by her for her different produflions.
/^/^ '^•^ V\^
^W:<Ms>^^^^^
M ,
Of an Animalcule or f mall livwg creature, zvhich is fometimesfound in
the livers of Sheep and other beajls.
O make my obfervatioiis on this fiibjedl the more intelhgi-
ble, I fliall place them in the following order : Firft, as to the
fliape and make of this animalcule ; Secondly, the part of the intef-
tines where it is found ; Thirdly, its numbers, and the manner of
its propagation ; and Fourthly, how thefe creatures, and other ani-
malcules of a fimilar nature, by fixing themfelves in the liver and
other internal parts of the body, can produce certain difeafes, and
their fatal confequences.
Firft, as to the fliape and fize of this creature, and its fimilitude
to other known animals ; it bears a near refemblance (in miniature)
to our fole or flounder, as appears ^y fig- A, which reprefents it of
the fize it is commonly found ; this figure fhew^s the back or promi-
nent fide; and/^. B, the belly, or flat fide of it. C is one of the
young of the fame fpecies, fliewing the back, D the belly of the
fame ; E and F are figures of the fame creature, fomewhat magni-
fied, and fhewn in the pofitions before mentioned.
Thefe animals are not often feen alive, becaufe the difeafe they
produce does not always fliew itfclf by outward tokens, and the
beafl: affli6led with them, fometimes feems fat and in good health,
and then the liver is not perhaps examined till fome time after the
beafl: is killed ; and fhefe creatures cannot endure cold, but if by
being expofedto it they are.deprived of motion, they will revive, if
the liver be held in a warm hand or put into warm water. Their mo-
tion is undulating or wriggling like that of the fiflies before men-
tioned, their colour a yellowifli brown, the belly quite flat, and
a
( 'O
much paler coloured tlinn the back, the fkiii rough and covered
^vith prickles or points, and fo traniparent, that the bowels and vei-
fels may plainly be feen on botli fides. The head wliich is fliewn
confiderably magnified, at letter G, is of a pointed form, plano-
convex, that is, rounding above and flat below, the mouth projeft-
ing, open, and of an oval Ihape, nearly in faihion like a carp. The
eyes, which are pit^hircd feparately at H and I, are very prominent,
and furrounded with a cartilaginous or griftly ring, which is Ihewn
at K, and they are placed, as we fee in many flat filhes, both of them
on one fide of the back, with a divifion between tliem.
Tiie heart is fo near to the head, and the bowels fo clofely con-
joined to the heart, that I queftion whether there is any thing, pro-
perly to diRinguilh the head from the reft of the body, which yet in
moil animals are feparate and diftindl. From theheait, arifc twovef-
fels fpreading over the whole bod}-, with a wide fpace between them,
extending almoft the whole length of the back, as reprefented at
letter L, and between thele vellels are many Imailer ones, as fliewn at
M, which are fo minute that no moifture can be difcovered witiiin
them. I obferved in the larger vedels two forts of juices, namely, in
fome a yellowilh brown, and fometimes a kind of purple ; in others a
pale green, both of a glutinous or flimy nature, and yet flowing in
tlie vcfiels even after the death of the animal, towards the heart, if
lield up by the tail, and back again, upon the head being raifed.
The excretory dufl, or pallage of the bowels, is in an unufual
place, being on the right fide of the body, clofe under the head,
for which reafon the inteftines are as it were, crowded together in
an heap. There is a fmall protuberance at the beginning of the
bowels, which I take to be the liver, and between this and the
bowels, I find in all of tliofe animalcules which I have ex-
amined, an innumerable quantity of oval particles, hundreds of
which, taken together, are not equal to the fize of a grain
of fand. They are of a pale red colour, and I take tliem to
( c )
be the fpav/n or eggs. Notwithflanding my mofl diligent exami-
nation of thele creatures, I never could difcover any difference of
fexes ; and it I'eems to me moft probable, that they are of that
I'pecies called Hermapin-odites, or every one equally prolifick ; at
leaft, none has ever fallen into my hands which appeared plauily to
be a male. The tail, though of the lame texture with the reft of
the body, is much tenderer, breaking or tearing upon the flightefl:
touch.
The parts in feveral animals wherein I have hitherto found thefe
creatures, are only the vellels, tubes, and channels wherein the
gall is formed and collected, though mofl commonly in the liver ;
and here they may be fa id to fwarm, producing grievous Iwel-
lings, callofities, contorfions, and fmufes in the part; and cavities,
which will be often found an inch and an half in diameter. In thefe
parts thefe noxious animalcules are found in heaps, and the places
where they lie, become hard and cartilaginous. In the fmall gall-
du6ls they lie longitudinally, and fometimes rolled or curled up to-
gether ; and I believe that many perions have hereby been led
into a miftake refpe6ting the Ihape of them, defcribing them
to be oblong, round worms ; but in truth, however clofely they
may be thus rolled up, they will I'pread open again, even after they
are dead, upon being thrown into warm water, for then they re-
cover their flat fliape, but at the fame time they become rather of a
paler colour than they originally were.
Thefe creatures are commoiily found in great numbers, though
in this particular they vary much, as it depends on their having
had more or lei's time to propagate ; I have taken out of one liver,
870 in number, befides many fragments, and exclufive of thofe
which were cut in pieces or deftroyed in opening the liver. And
in another liver I have leen but ten or twelve.
They are found in many different kinds of beafls. I iKn'e been
a 2
( cl )
informed by Hunters, that they have found them in Stags, ^vlId
Boars, and other kinds of game, both great and fmaU. I myfelf
Iiave leen them frequently in Calves, and once in a young Bul-
lock. Sheep are infcfled by them even from tiie vomb of the
parent, and Lambs of a ^ear old and upwards, as well as aged
Sheep.
As to the production and propagation of thefe animalcules,
I confidcr as idle talcs, what {'ome writers aflert, of their being ge-
nerated by putrefac^tion or decayed fubdances, immoderate wet
or heats, and other equally feniclei's imaginations ; and I lay it
down as a certain truth, that thefe, as well as all other fmall
living creatures, are produced from their like, by the means of
eggs, feed, or fpawn, according to the nature implanted in them
at their iirft creation. And it I'eems to me moll probable, that
thefe animals, with their eggs, find their way into the bodies of
Sheep, (and which we may fuppofe to be the cafe alfo witli other
infedls and their eggs,) in the following manner ; namely, that in
wet fummers and autumns thefe animalcules, which are originally
bred on the furface of the earth, may, with the water in which
they live, be i'wallowed by the Sheep ; and I have been confirmed
in this opinion by converfing with Countrymen, Huntfmen, and
Butchers, on the I'ubjcdl. But I am not of the opinion that
after being fwallo\\ed, they do tiiemfelves force their way
out of the Itomach and bowels into the gall-bladder ; I rather
conclude, from realbn and my own experience,* that their fpawn
or eggs may, with the oily part of the chyle in the infefted beaft
* It muft fsein ftrange to us that a creature, originally bred in the water, (hould find a
proper receptacle for its life and growth in the warm bowels of an animal ; and yet we
d.iily fee leeches, which are alfo bred in the water, and perfedly cold themfelves, fuck the
warm blood of the human fpecies with an avidity fcarcely to be paralleled. But, as
Mr, Leeuwenhoek, in one part of his works obfcrves, we may wonder at thefe operatioiis
of Nature, but admiration, and nothing more, will be the refult of our cogitations.
( « )
be carried into the veflels of tlic gall bladder, and there fix them-
felves ; forafmuch as thefe vellels are lined with a (limy and te-
nacious fubllance, and alfo bccaufe the gall is not like the blood,
in continual circulation, but is retained in its vefTels, or emitted, as
the calls of the animal oeconomy require. Again, they are found
fwarming in the liver, where they produce tumours and callofities,
and caufe the colour of it to chan2:e. And it ieems to me not at all
furprizing that thefe animalcules Ihould live and be nouriflied in the
juices of the gall, for every living creature has a fituation and I'pecfes
of food peculiar to itfelf. Sea-fiih die in frefli, and river-fifli in fait
water. A worm cannot live in the air, and a fowl expires in the
earth. What wonder is it then that the creature of whicli we are
treating, when introduced into the body of another animal, Ihould
find its peculiar place of life, growth, and increafe, in the vefTels of
the gall, and in the gall itfelf ?
In the laft place, hke as we experience, that many living crea-
tures arc found in the human body, producing difeafe, pain, and
death itfelf ; fo it is my opinion, that the animalcules of which I have
been treating, and which arc fometimes found together by thou-
fands, may produce the following mifchievous confequences :
Firft, the extraordinary diftenfionof the parts where they harbour,
as well by the growth and increafe of their own bodies, as by the
multiplication of their fpecies or brood.
Secondly, by their biting or gnawing the parts they infcft, lo as at
length to break or deftroy their texture ; and thus wholly, or in
part, render them incapable of performing their funftions.
Thirdly, by forcing their bodies into the fmall tubes, and veflels,
whereby the delicate frame of thofe tender parts is torn afundcr.
Fourthly, by obftru6ling the paflages in the veflels, whereby the
circulation of the juices is prevented, and an inflammation enfues.
Fifthly, by devouring and confuming the nutritive juices, whereby
( f )
the adjacent parts nro deprived of their fiipport and nourifli-
ment.
Sixthly, by clogging the vcdiL^s with their excrements, their eggs
or fpawn, and the bodies of fuch of the animalcules themfelves as die,
wliereby the motion of thofe parts being impeded, the moft fatal con-
Icquences follow.
There are many otlier ways in which thefe creatures may prove
noxious to animals, but thofe wliich I have here enumerated may be
fufficicnt to give an idea of the reR.
He, then, who can find out and pra6tife a method whereby, with-
out injury to the parts of the body where thefe vermin harbour, can
prevent their gnawing the parts, their creeping abovit in tlie inteftines,
and, what is worfe, their dying there ; or rather, can difcover how to
expel them, while alive, out ofthebodj', will in this refpe6t bid fair to
eff"c6t a cure. It is laid down as a truth, that a diltemperaturc of the
blood and juices, whether proceeding from an ill conftitution thereof,
or from an interruption in the circulation, can caufe many difeafes
and their ill confequences : but muit it therefore be deemed unrea-
fonable to attempt proving, that animalcules being found in tlie
juices, or even in the more I'olid parts of the body, may alfo produce
difeafes ? The firft of thefe points is mere matter of theory or argu-
ment ; of the fecond, more certain proofs can be brought ; confe-
quently, it feems more rational, that thofe perfons, who altogether
rely upon their experience, fhould, in their enquiries, diligently in-
veftigate the reafons on which they found their opinions.
I forbear to fay any more on this fubjeft, forafmuch as what I have
written is only for the improvement of medical knowledge, and as
an incentive to the laborious enquirers after new difcoveries in fci-
ence, the field of which, is indeed indefinite.
f
-;s-
ADDITION, BY THE TRANSLATOR.
IT is proper to inform the Reader, that the preceding EHay has
not Mr. Leeuwenhoek for its author, but is taken from a letter writ-
ten to liim on th,e lubjedl by G. Bidloo, a profedional gentleman at
Leyden, under date of the 21ft March 1698, and publilhed in the
Dutch Edition of Mr. Leeuwenhoek's Works, tliough it does not
appear in the Latin Verfion ; but, as the fubje61: is interefting, and
probably tliis Eday has not before appeared in any other than the
Dutch language, the Tranflator thouglit that it might be acceptable
to tlie Englifli Reader.
Since the perufal of this Eflay, the Tranflator lias had opportuni-
ties of converfing with feveral judicious Gentlemen, who are conver-
fant in the grazing of Sheep, from whom he has collected the follov/-
ing particulars :
That in vei'y wet feafons, particularly towards the latter end of
the year, a fpecies of grafs fprings up in the low and wet lands, by
feeding on which, the Sheep are fuppofed to contraft the diftemper
called the Rot. That, if the rains do not abound, until after the win-
ter froft has been experienced, the Sheep are not then obnoxious to
this difeafe, but othervvife, if a wet feafon precedes the froft ; and
laftly, that Sheep infedfed with this difeafe, do, for a time, appear fat
and healthy, but, when tlie diibrder gets to a height, they fall away
rapidly.
Thefe particulars feem to prove, tliat the difeafe called the Rot
in Sheep, docs in fa6l proceed from the animal defcribed in the
preceding Efi'ay, whic'n, being bred in the water, and adiiering, with
its eggs, to the grafs growing in watery places, is fwallov/ed by the
Sheep. And, it is probable that wlien the froft precedes a ^vet fea-
fon, tlie animalcules and their eggs are killed by the froft, and con-
fequently tlie Sheep efcape : we may alfo conclude, that while this
noaous anijnalcule is in an infant ftate in the bowels of the Slieep,
( 1^ )
it may not he particularly injurious, but when it arrives at a fizc
to prey upon the liver, firfl, a ficknefs, and wafting in the animal,
and afterwards, deatli mufl enfue ; and the Tranflator has been in-
formed by a gentleman's Gamekeeper, that he has frequently found
Hares, dead of this difeafe, and that upon opening them, hundreds
of the animalcules were found in their livers.
Thefe particulars tlie Tranflator thought proper to notice, leaving
it to thofe who arc qualified, to exercifc their medical Ikill in the dif-
covery of a remcd}' for this fatal diftemper.
The animalcule before defcribed is called in fome parts of England
a Fluke, in others a Loop, but moft generally a Flounder, probably
from the rcfemblance it bears to the fifli of that name.
* The Author s opinion and reafoning refpedling the formation of that
fpecies of fuel which is called Peat-f, and alfo zvith regard to the trees
dug out of thofe places zvhere Peat isfound: from whence he takes occa-
fion to propofe and difcufs a queftion, whether the Sea may ?iot, in
procefs of time, become more elevated in refpeSl of the Land.
1 HAVE heard many perfons deliver their fentiments, refpe6ling the
manner in which that fubftance called Peat was produced in this
country of Holland. The general opinion is, that the place where
this Peat is found was, in former ages, nothing but a wood, and that
the falling leaves and fmaller branches or twigs of the trees, colle6ling
together on the earth, did in procefs of time, produce this fubftance,
which is by us called Veen. It is alfo believed, that thofe trees,
numbers of which are found among the Peat, formerly grew in the
fame place, and were all blown down by fome violent tempeft of wind
* In this Enay, the Author departs from his iirual method of invcltigating the works of
Nature by the microfcope, and proceeds upon theory- It will be feen, however, that he
does, in one inftance, draw a very flrong argument in fwpport of his hypothefis, from microf-
coplcal examination.
+ The words Peat, and Turf, are fometimes ufed promifcuoufly, though their true
meaning is very different. Turf, properly fo called, as denoting an article of fuel, is
compofed of the thick roots of grafs, pared off the furface of the earth on commons, and
dried in the fun. The bark of oak, after it has been ufed by the tanners, made up into
fquare pieces or cakes, and dried, is fold in London for firing, under the name of Turf. But
Peat, of which the author here treats, is found under the furface of the earth, fometiines to
a confiderable depth.
T
( h6 )
from the North -Weft, and that for this reafon, the roots of all the trees
fo dug up at this day do point towards the North- Weft.
Thefe opinions I have often controverted : for how can it be
imagined, that fo great a quantity of Peat could be produced from
trees ftanding together in a wood ; inafmuch as Peat is in fome places
found coIle6led to the thicknefs of ten or twelve feet, and fometimes
more ? Neither can it be conceived, how thofe large oak trees, which
are newfound, lying in the midft of the Peat, could ever have grown
to their full fize in fuch a foil, for, a common ftorm of wind would
have been fufhcient to blow them down.
Again, it is well known, that thofe trees which are found at a confi-
derable deptli in the Peat never have on them the fmall brandies on
the ftem, nor any fmall ramifications on the roots, and all thofe fmall
light branches of alders and willows which are found in Peat, are not
(as far as I have ever known) firm or folid in their kind.s,. but very
much decayed, the fame as if they had beezi for feveral years e.xpofed
to the air, or had died and withered on the trees, or were almoft rotten.
Tiiefe deca3'ed portions of wood cannot, as I conceive, have grown in
the places where they are now found, but muft have been carried
thither by fome flood, or ftream of water, and that they either floated
on the water, or had lain expofed to the air for feveral years, and
tiicrefore may properly be denominated decayed wood ; and I
remember, that on handling fome pieces of willow about the thick-
nefs of a finger, which I myfelf faw dug up, I found them as foft and
flexible as a withered carrot.
Now, if thofe oak trees, which are found at a great depth in the
Peat, had originally grown in the fame place, fuch trees would
certainly be found with the fmall branches on their ftems and roots,
if not in the whole, at leaft in part, and thofe not decayed, for in the
very fame places there have been found in the Peat, hazle-nuts, with
their Ihells entire.
( it7 )
We know that thefe trees lye eight or ten feet below the furface of
the Peat, which furface is, in fome places, four feet lower than the fea
at low water ; how, then, can it be conceived that thofe trees could
have grown in fuch low lands, unlefs we fuppofe that the level of the
fea was at that time full twenty feet lower than it is at prefent ?
To this may be added, what I have myfelf been an eye-witnefs to,
that a violent ftorm from the North- Weft has fo agitated that river
which we call Hollands Diep, or Haring Vliet, as to tear up from the
bottom large portions of a fubftance fimilar to our Peat, but fo light,
as to be carried by the waves againft the banks, and there left, fome-
times in pieces larger than a cart-load, which fubftance I was told the
poorer fort of people carried away for fuel. Now, it is impoftible that
this Peat-like fubftance raifed from the bottom of the Haring Vliet, and
which, like Peat, is compofed of leaves, fmall fibres of the roots of
trees, and other vegetable fubftances (and who knows how deep the
bed thereof may be ?) could ever have grown in that place.
I once faw Peat taken up from the depth of ten feet, in a watery
place, where it had never before been dug. I examined the texture of
it, and found it in part to confift of an herb called heath, which herb
does not grow in our Peat-lands. And I have alfo feen Peat dug up at
a confiderable depth imder the fands, not in regular ftrata or beds, but
in broken interrupted patches, and fometimes in a large body colle6fed.
This Peat I examined, and found that it cohfifted of leaves of trees,
the roots of gi-afs, the ftalks of leaves, and very fmall pieces of wood ;
in fhort, there is no vegetable fubftance that grows wild of itfelf, but
what, upon an accurate inveftigation, will be found among Peat.
Some years ago, being on a journey at a fmall diftance on this fide
of Haerlem, I faw in a meadow by the road fide, a labourer digging in
the earth in a cavity as deep as an ordinary man's height ; and, being
curious to know what he was taking up, I alighted from my carriage,
and found that it was Peat which was laid by in pieces to dry for firing.
T2
( 148 )
In the place where this man ^\■as digging, the Peat lay only in Imall
parcels, or collected portions, and near the fame fpot there was not
any token or appearance of Peat. I was at the fame time furprized,
to fee lying on the fand among the Peat, a certain fubftance of
a fine blue colour, and I was told, that, near the place, it had been
found in a larger quantity, and enough of it colle6led to fill a fmall
caflc, which had been carried aw ay and fold.
At another time, in pafllng through the town of Helvoetfluys, I
obferved before the houfcs of feveral poor people, parcels of Peat piled
up to dry, and I was told that it was good fuel, but produced a difa-
greeable fmell, and that it had been dug out in enlarging the dock for
Ihips; and on breaking fome of this Peat in pieces, I perceivtd in it
fome fmall fliinin-g particles, which induced me to carry home a fmail
quantity of it, that I might examine it by the microfcope.
I was informed, that this Peat was d g in a place where tliere had
formerly been a dyke, or bank againft the lea, and that the peat did not
lye i na regular bed, but only in three places, and that under it was the
kind of fand we call klapzand, all which, upon examination, I found to
be as related. Hereupon I concluded, that this fand, called klapzand,
had in former times been the fea-fliore, and that the Peat had by floods
been brought to tlie three places where it was now found, and afters-
wards covered with fand from the fea, or that wafhed down the river.
On my return home, 1 examined this Peat by the microfcope, and
found, that the before mentioned fliining particles were the feeds of
fome plant, which, if they had been larger, might have been taken for
beans, but thefe were fcarcely the fifteenth part of an inch in diameter.
Other fliining particles I alfo obferved in this Peat, which, upon a
more accurate examination, I found to be pieces of the fkins of thofe
flying infects which are produced by tranfmutation from maggots or
caterpillars, who hide themfelves in the earth ; and, among others, I
fa\v fome pieces of an infed of the beetle kind, which, as it frequently
( 149 )
creeps into the earth, has its wings covered with a kind of (hell or
eafe for their defence, in like manner as we obferve in thofe infcdts
which are called by children cockchafers and ladybirds.
I alfo difcovered divers pieces of the bodies of various fmall animals,
in which I could diltinguilh thofe little cavities or fpots whicli are
obferved on infects, particularly on the cafes covering the wino-s ;
alfo on fome of thefe fragments I faw very minute hairs, fuch as the
bodies of infe6ts are generally covered with, likewife fome fragments
of wings with hairs on them. 1 found alfo a kind of fting of fome
infe6t, and at the extremity of it an aperture, fuch as is feen in the
fting of a fcorpion ; in a word, I found an incredible number of
particles or broken fragments of infedts of various kinds and fizes,
confidering the fmall quantity of Peat in which they were contained,
fo that it may fairly be concluded, that all thofe infefts had been
promifcuoufly colle6led together when the earth on which they lay
had firfi; been waflied away..
In the fame portion of Peat were various particles, appearing to the
naked eye li!;e the ftalks of grafs or plants, and fuch I found them by
the microfcope to be, and by it I plainly perceived the tubes or veflels
of which they were compofed. I alfo difcovered fome few particles,
which feemed to be thehufks of feeds, and others which I imagined
were the rinds or bark of twigs.
All thefe particles, of the many different kinds I have enumerated,
were contained within the compafs of a portion of Peat not exceeding
a cubic inch in fize.
From thefe obfervations it appears, how incorruptible are fome
fubftances, when buried deep under fand and water, when the fame
fubftances being expofed to the air, and in frequent agitation, are fo
divided and broken that they efcape our fight, and then we fay they
perifli ; and who knows whether this Peat-like fubftance might noli
have lain for fome thoufand years under the fand and fea water before;
the place became firm land ?
( 150 )
It is well known, that not only in Holland, Guelderland, and Utrecht,
but alfo on all the fea-coaft, as far as Holftein, much Peat is found ;
and if it be true, as is generally believed, that not only England and
Scotland were formerly united to Ireland, but that the Orcades, Shet-
land, and Faro, and tlie other fmall iflands near them, were formerly
united (which iflands being rocks, or rocky on their fliores, are able to
refift the force of the fea), and that in thefe iflands this Feat-like
fubihmce is alfo found, we can without much dilliculty folve the
queflion, if we fuppofe that thefe larger and fmaller iflands, by
violent ftonns and high tides of the ocean, may have been feparated
from each other, and tliat the earth or foil which was then carried
away, was covered with various trees, grafs, and herbs ; aU thefe fub-
ftances floating on the fea, might, b)^ the tides and North-Weft winds,
be driven to the places where they now lie; and the trees which we
find lying with their roots pointing to the North-Weft, muft of
necefllty be depofited in that pcfition : for, as the roots of trees are
heavier than the upper parts of the ftem, thofe roots muft fink dcepeft
in the water, and, being dragged along the bottom of the fea, the ftems
would be driven foremoft, and caufe the trees, when waflied on the
land, to lye with their roots towards the North- Weft. The heavier
fubftances, as fand and clay, which had conftituted the foil fo carried
away by the fea, would, by their weight, fink to the bottom, and, taking
the fame courfe with the Peat, would be thrown upon it, and produce
a fandy fliore, as we now perceive it.
It is further to be confidered, that our rivers, the Rhine and the
Maes, do every year bring down with them great quantities of foil,
and particularly in the fpring time, becaufe at that feafon, by the fun
and rains, the fnow is melted on the tops of the high mountains, and,
running over the lands, waflies away with it great quantities of fand,
clay, and earth, and thefe, by reafon of the fwift current of thofe
w-aters, find no reft until the rivers, becoming wider at their mouths,
( 151 )
and meeting alfo the flood from the fea, tlieir current is diminifhed,
and the fand fubfiding, produces fhallows. In thefe lliallcws, the clay
and earthy fubftances alfo fettle, becaufe in thofe places the waters
have little motion, in proportion to what they have higher up the
rivers, and, by this means it is well known that there is a continual
increafe of dryland in fome parts of our fhores.
If we obferve attentively our fea-coarts, we fliall in fome places, even
thofe which the fea daily breaks againft and wafiies over, obferve large,
pieces of black earthy matter, very compa6l and clofely cohering, and
which lye partly covered with fand, and partly overflowed every tide.
Thefe portions of earthy matter fo depofited, produce a flrong argu-
ment, to convince us that our fliores thus wafhed up by the fea, were
not merely formed by fmall quantities of foil gradually depofited, but
by large portions or fragments of land. And, who knows how long
fuch fragments of land might, by reafon of their gravity, lye at the
bottom of the fea before they were thrown upon the fhure, which, in
all probability, could not be effe6ied otherwife than by violent ftorms,
and that, many years after the flioaly or fandy bottom v/as firft formed.
The magiftrates of Leyden had it lately in contemplation, if it
could have been done, to make a channel, outlet, or opening for
water, into the fea at Catwick, in the place where the Rliine for-
merly difembogued itfelf; but they found the undertaking to be
impradlicable, by reafon that the level of tlie fea was too high at
tliat fpot. This, at firft, appeared ftrange to me, as I could not con-
ceive how the fea could obtain a greater altitude than in former ages,
feeing there is not a greater portion of waters on our teiTaqueous
globe, than at its firfl: formation. But the difficulty ceafed in my
mind, when I confidered, what quantities of fine fand and flime, or
clay, are continually carried down our rivers, infomuch as to make
firm land, where formerly it was deep water; and further, what large
rivers there are in other parts of the world, all which carry great
( ^52 )
quantities of fiich fand and (lime into the fea ; whereby, at tlie
mouths of thofe rivers many levels of marfli land are produced, while
on the other hand, moft countries far diftant from the fea are moun-
tainous.
If we tlien conclude, that, by all thefe rivers, a great quantity of
fand and earth, and whatever is heavier than the water, is dcpofited
in the fea, it necelTaril}^ follows, that the feamufl: from time to time
be inore elevated. Again, by earthquakes, large portions or tra61:s of
land ai'e buried in the fea, leaving nothing but lakes in their place ;
and we have inftances of a volcano or burning mountain cafting fo
many rocks and flones into the fea, as to raife illands where before
it had been deep water.
In the year 1692, by an earthquake in the ifland of Jamaica, a
large fpace of land was fwallowed up, and converted into a lake ; and,
at the dillance of thirty miles from the fea, two hills, by the fide of
a river were thrown down, caufing the river to take another courfe ;
from which new channel, a great quantity of earth muft have been
carried into tire fea : and although the coafi; of Norway, and that of
Ireland, Scotland, and part of England, are rocky cliiTs, yet their
rivers muft continually carry much folid or heavy matter with their
waters, and, tlie beating of the waves againft the cliffs, will carry
thefe kinds of fubftances into the bottom of the fea, and fo elevate
its furface.
To fome perfons this aflertion may feem ftrange, as judging that
the great extent of the fea bears no proportion to the fmall quantity
of earth which the rivers wafli into it ; and that therefore, the fea
cannot be fo much elevated, as to make any peixeptible diif erence in
feveral hundred years.
In order to fet this matter in a true point of view, I have made a
quellion with myfclf : Suppofing the mountain called the Peak of
Teneriffe, to be funk in the fea, what elevation would it produce in
( 153 )
the general furf ace of the water ? Now, (confidering the whole of
this globe to be one third part land, ^nd two thirds water) I compute
that the whole furface of the waters would be thereby raifed between
one fourth and one third of an inch. And, fuppofing all the rivers in
the world, which are very numerous, (for according to our maps
Spain and Portugal only, contain one hundred) do yearly carry with
their waters into the fea fo much earth as is equal in fize to one half
of the Peak of TenerifFe, the fea would, in the fpace of one hundred
years be elevated nearly two feet.
This being fo, it is not to be v/ondered, that we find our flood tides,
in flrong winds from the North-Welt, to rife higher than they were
known to do in former times, and that the Rhine, which heretofore
fell into the fea at Catwick, cannot now have any outlet that way ;
and laftly, that on the fame account, we are obliged to raife our dykes
higher than formerly. Indeed, we may conclude, that if in a courfe
of many years, there fhould not be more fpace gi\'en to the waters of
the ocean, by earthquakes or fubterraneous fires, producing cavities
in the "deep, the low lands near the fea will at length be overflowed.
As to the quantity of land excavated in digging Peat, which fome
may imagine affords room to the waters, the fpace of earth or foil
fo taken away, does not, in my judgment, amount to a thoufandth
part of the fand and clay which is brought down the rivers, and be-
fides, the places fo excavated are, for the moll part, afterwards
drained.
U
0« the effedls of Acids in the Stomach, and the vfe of Fifl? Diet, xvith
a particular defcription and examination of the liquor orfubjiance
named Runnet, which is ufed in the making of Cheefe.
It is the opinion of many medical peribns, that various dilbrders in
the human frame are caufed by acid in the ftomach, which coagulates
the juices ; and fome condemn the ufe of acids, and alfo of fifh, as
articles of food. But to thefe opinions I cannot fubfcribe, for, at a
town in my neighbourhood, where the people get their living by fifh-
ing, and principally feed on fifli, efpecially when they are on the fea,
the men are very robuft and healthy, even to a great age ; and, with
refpe61; to myfelf, I have experienced, that, when my habit of body
has been indifpofed, I have been greatly refrefhed by eating fifli,
with fauce compol'ed of a mixture of butter and vinegar, and I never
found acid fauces difagree with me. It is alfo my opinion, that a filh
diet is more wholefome than flefh, particularly to thofe perfons who
do not ufe much exercife, becaule filh is more eafily comminuted and
digefted in the ftomach and bowels than flcfli ; and, as flelh affords a
more nutritious fubftance, fuch fuperabundant nutriment is, in my
opinion the fource of many difeafes. And, I think it may be made
appear, that the coagulation or curdling of food in the ftomach,
when caufed by acid, is not prejudicial, but rather conducive to
health.
In the markets which are held weekly in our tovra, it is ufual to :
expofe to fale, that part of the inteftines of calves wliich is called:
' ( ^6o )
the Maw ; this is Hilted, and kept in calks, and, with the jiickle in
which it is preferved, goes by the name of Runnet. It is purchaied
by farmers, and when poured on milk* curdles it, of which curd,
cheefe is made. Some of this pickle I purchafed, in order to examine
it more accurately, but was obftrufted in my enquiry, by the numbers
of faline particles in it,
I therefore purpofed to procure from a butcher, fome of the liquor
when newly taken out of the maw, as foon as the animal was killed ;
and I was informed, that if a calf had fwallowed any milk a few hours
before it was killed, there would be found in its maw a quantity of
coagulated or curdled milk, which it was cuftomary for the butchers
to take out and preferve with fait in ajar, (fome of which curd was
lliewn to me), in order to fell the fame to the farmers, who found by
experience that a fmall portion of this curdled milk, was of more
ftrength or virtue for their purpofe, than the liquor in which the maw
was pickled.
I then went to another butcher's, where I faw the maw of a calf,
wherein, although the animal had not fucked for the fpace of t^^'enty
four hours before it was killed, I perceived fome portions of curdled
milk, larger than a walnut ; thefe I caui'ed to be waflied in clean
water, and carried them home with me, and I was much furprized to
find them as hard to the touch as new made cheefe.
This curdled milk I put into a glafs, and poured on it rain water,
fo as to cover it about an inch, and then broke the curd into fmaller
pieces, in order that the faline particles, if any there were in it, might
be diflblved by the water ; and, after it had flood thus for fome hours,
I ftrained the water through a filtering paper, into a new and perfectly
clean glafs.
*Kinnfn in German, and roitnen or runncn in Dutch, mean to curdle j this gives us the
true derivation of the word Runnet.
( 156 )
Some of this filtered water I poured on a portion of wine, in order
to fee wliether it would have any effe6l on the faline particles which
are in wine, but, after it had flood feveral hoars, I could not perceive
any alteration ; I therefore determined to try the experiment with
vinegar. And, as the vinegar which is commonly fold, is forthemoft
jiart adulterated, I took \\ hite wine vinegar, which I had kept with
marygold-leaves in it for five and twenty years, and was uncom-
monly firong, and mixed with it a fmall quantity of the before men-
tioned liquor, but I faw no other faline particles in it than thofe
which are found in vinegar. I obferved, indeed, feveral globules of
oil, which in all probability proceeded from the mar3'^gold flowers.
But, W'hen I took a fmall quantity of new milk, and mixed with it a
very little of the before mentioned water, on bringing it before my eye
as foon as I poITibly could, I faw moft of thofe round particles
which caufe its white colour, curdled together, and an inconceivable
number of fmaller particles, fwimming among the curdled ones, from
whence I concluded, that thefe fmaller particles were of a different
nature from the coagulated ones ; I alfo faw in the fluid or whey
various pellucid globules of different fizes, the fmalleft of which were
jio larger than globules of blood, and the largeft of thefe pellucid
globules were twenty-five times that fize ; all thefe I concluded to be
tliofe particles in the milk, of which butter is compofed.
From thefe obfervations it "appears, that this liquor called Runnet,
which coagulates or curdles milk, does not take any effeft on wine
or vinegar, neither of which are adapted to the food of calves.
I was informed by the butcher, that the fame curdling of milk,
took place in the flomachs of fucking lambs ; and moreover, that if
lambs were taken from their dams and fattened with cow's milk,. it
would be curdled in larger quantities, by reafon, (as he judicioufly
added) that ewes milk has more particles of fat in it than that of
QOWS.
( 1.07 )
After this, I mixed new milk with a large quantity of Runnet, to
fee whether thofe fin:iller particles v/hich I have before mentioned to
have feen fwimming in the whey, would thereby be coagulated, but
they ftill continued to preferve their figure.
Upon examining the before-mentioned filtered liquor by the mi-
crofcope, I faw in it an inconceivable number of uncommonly minute,
particles, to v.hich, by reafon of their exceeding fmailnefs, I could not'
give any other name than that of globules.
Whether the gLbules or falts in the Runnet, have fuch an effedl:
on rain water, as to caufe any of its particles to coagulate, fo as to be-
come vifible by the microfcope, I have not yet been able to difcover.
I feveral times tried the experiment of pricking my finger with a
needle, and, immediately mixed fome of this liquor with the blood, to
fee whether any of its particles would thereby be coagulated : on
viewing the fame through the microfcope, it exhibited a curious and
pleafant fpe6lacle of vafl: numbers of the globules of blood, rolling
one over another, but they were lb far from being coagulated by the
mixture, that they feemed more fluid than before..
After this mixture had flood about the fpace of half a minute, 1
perceived in it many fmall pellucid particles, which by degrees grew
larger, but yet were fo minute, and fo much covered by the circumja-
cent particles, that I could not clearly difcover their figure ; but, to
the bed of my judgment, they were irregular faline particles, appear-
ing all of different fliapes, and adhering together, in like manner as
we obferve in fugar-candy. Now, whether this appearance was com-
pofcd of lalts in the blDod, or falts in the milk, or both, I am not
able to difcover.
I feveral times applied a drop of the before-mentioned filtered
liquor to my tongue, and I judged it to have more of a bitter than an
acid tafie ; whereupon I confidered, whether its property to curdle..
milk, might not be derived from the gall.
( 158 )
I therefore went to a butcher's, to fee whether the gall was not
emptied into the maw, but 1 found that the gall bladder did not dif-
cliarge its contents into the maw, but farther down, where the bowel
grows narrower ; this gall bladder I caufed to be cut off ib as to leave
the vefiel through which the gall palVes, joined to the bowel, and
having bound both ends of thefe with a thread, I inflated the gall-
vefl'el witii wind, but I found the parts to be fo contrived that not the
leafl: portion of water, or even of air, could pais out of it into the
maw.
When fome of this Runnet had flood with a little water on it in a
glafs, for the fpace of two days, it acquired as acrid a fmell, as we per-
ceive in four curdled milk.
I at one time, received from a butcher, the gall bladder of a calf,
which was entirely void of gall, whence I fuppofed that its contents
liad been I'pilled by accident, but I afterwards underftood that no gall
had been in it, and tiiat the like appearance was often obferved.
But, what Ihall we fay, when we fee in how high eltimation tobacco
is held, and acids altogether condemned ; as if all our bodies were
exa611y of the fixme difpofition 6r conilitution.
For my part, I have for many years been ufed to fmoke tobacco for
the cure of the tooth-ach, but I have often found that before I fmoked
half a pipe, I was fo fick, as to be obliged to lie down near the fire, and
fo much difordered, that I could not even endure to be fpoken to ;
whei-eas, on the contrary, every kind of acid, whether ufed in food, or
taken by itfclf, agrees perfe61Iy well with me. In fliort, we can
much better judge for ourfelves as to \\ hat agrees or difagrees with
our conftitutions, than pretend to advife other people what is good
diet, or the contrary.
With regard to the curdled milk, which I have mentioned to be
taken out of the calf in hard pieces, it feems to me probable, tliat the
milk at firfi; was but lightly curdled, and that the frequent contrac-
{ -^59 )
tions of the bowel where it lay, which in the courfe of nature are
performed many times in a minute, were the caufe of its being found
in that ftate.
Seeing now, how powerfully coagulation is performed in animals,
we may conclude, that fomething of the fame kind muft take place
with the food in our own flomachs, in order to render the fame nu-
tritive to us. And who can tell, how far fuch coagulation ma}'^ take
place, not only witli milk, but alfo with wine, vinegar, fait, and
other parts of our food ? This, however, is certain, that if a fuckhig
child cafts up the milk, on account of having fwallowed more than its
llomach can contain, fuch milk, though juft before taken from the
breafi:, is in a curdled ftate ; confequently we mufl conclude, that
coagulation in our ftomachs is a neceflary part of the animal oeco-
nomy.
If milk in the ftomachs of fmall animals was not curdled, it
would in a few hours pafs through their inteftines, and afford but
little nouriflimcnt to their bodies. And, in this opinion I have been
confirmed by the experience of the butchers, from whom I find, that
when the excrements of calves or fucking lambs are thin and fluid,
they thrive but little, and, that at thofe times, no curdled milk is
found in their ftomachs.
I am aware, that thefe my obfervations, may difpleafe fome
perfons, as thinking that herein I am going out of ray province ;
but, thofe con fi derations weigh little with me, forafmuch as every
judicious perfon knows, that Phyficians themfelves, in many things
proceed merely by guefs, and therefore, I allume to mj'felf the liberty
of offering my conjectures on this fubje6l.
4-
*^'#?Sc'-=-^'^
( KJo )
ADDITION BY THE TRANSLATOR.
Almofl; all the arts, which contribute to the fupport or comfort of human
"life, have been the rcfultof long and repeated experience. I will inftance in the
two moft necclTary articles of food, which arc bread and beer, refpetling
which, a celebrated writer of the lafl; age thus exprelfes himfelf : — " The arts of
" brewing and making bread have, by flow degrees been brought to the per-
" feBion they now arc in, but, to have invented them at once, and, * a priori,
" Vould have required more knowledge and deeper infight into the nature of
" fermentation, than the greatefl; Philofopher has hitherto been endowed with ;
" yet the fruits of both, are now enjoyed by the meancft of our fpccies."
Cheefe, however, another principal article of food, at lealt among the
poor, was moft probably brought into ufe, a priori, by adverting to the
change made in milk, from a fluid to a folid, in the ftomach of the calf, and
by imitating nature in the manner defcribed in the preceding EfTay. To
-prcferve the concreted or hardened fubftance, in a wholcfome ftate, for a
length of time, human invention added fait, and, by thcfc two eafy operations,
is produced that, which is now a luxury to the rich, and a fupport to the
poor.
How the change in milk, by the mixture of Runnet, is produced, Mr.
1-eeuwcnhoek's induftry, we fee, has not been able to difcover; we can only
therefore admire the manner in which nature operates, to produce this efl'eEl.
For, there is no other known fubftance that fo effeQually curdles milk, and,
though the tafte of Runnet is of itfelf very naufeous, yet none of this difa-
grceablc taftc is imparted to the curd ; on the contrary, that which is called
cream cheefe, or new cheefe, being merely the curd, without any mixture of
fait, is of a fwcet and delicious tafte, and is produced as a dainty at our
tables.
* The exprcflion, a priori, means, in logic, or in pra£lice, to argue or to 3(51: upon known
and eftablifhcd principles, from whence a certain conclufion or efFe(fl cnfues; a fojieriori
means, where, arguing from the efFc^, we trace it backwards to its caufe.
Of the Snail or InfeStfound on the Vine, alfo on the nature of Sage, and
zvhence its virtue proceeds ; zvithfome obfervations on the manner in
xvhich different a?iimals emit their poifon.
j\. Gentleman of fome confequence in this country, upon a certain
time, put into my hands, a parcel of fmall whitifli eggs, together with
Ibme dry earth, in which they were found ; and defired that I would
endeavour to difcover what fpecies of animal would be produced
from them. The axis of thefe eggs was nearly equal to one fifteenth
part of an inch.
One of thefe I difre6led, and found in it a thin fluid, mixed with
round particles, or globules ; the reft of them I put into a glafs, but
their contents in a few days entirely evaporated, and the fhells, which
were very brittle and tender, upon the liquid they contained being
exhaufted, became fhrivelled, fo that no living creature proceeded
from them.
The following year, the fame gentleman brought to me fome
more of thofe kind of eggs, which I treated in the fame manner as
the former, but with no better fuccefs.
In the month of July, in the third year, I received from the fame
perfon a larger parcel of thofe eggs, which were mixed with about
an handful of moift earth.
Seeing this, I began to confider, that perhaps, the reafon why the
liquor being evaporated from the former eggs, had thereby prevented
their producing any living creature, was, that in dry earth they be-
X
( i62 )
came barren, and that in their nature they required to be kept jnoifl ;
confequcntly, that if I treated them in the fame manner as the former,
I fhoiUd never obtain my wifli to dii'cover their fpecies. I therefore
put thcfe, and the moifi: earth wherein they lay, into a glafs tube,
about ten inches long, and three quarters of an inch wide, one end
of which I had doled together by heat, and the other I flopped with
a cork, by which means wjiatevcr moifture might evaporate from
the earth, would be confined by the glafs, and, there condenfing, the
greater part of it would fall back on the earth, and keep it, and the
eggs, always moift.
This tube I placed in my clofet, fo as to be continually in the way
of my notice, and, after fome days, I faw, to my great furprize, two
fmall * Snails, of that fpecies which infeftthe branches of vines, (and
which are called bv us Wyngaart-flakken, Vine-fnails or Vine-flugs)
on the infide of the tube, and which had crept out of the eartli con-
tained in it.
I then took out of the tube an egg, or rather what was now become
a fmall Snail, with part of tlie egg ihell adhering to it, and put it into
a fmaller tube, in order to examine it by the microfcope more
accurately; and thereupon I perceived in one of the horns a very ra-
pid motion, performed in a veilel, apparently an artery, and wliich I
judged to be about one fourtli part the fize of an hair. This motion
was not an uniform or continued one, but by fits, or pulfes, and, fo
quick, that I judged the juices in the veflel were propelled forward,
three times within the period of one pulfation in the human body ;
and I concluded, that this veflel muft certainly be an artery, and not
fardiftant from the heart, becaufethe quick pulfations I have noted,
could not, otherwife, have been fo diftin6fly feen.
Tlie next morning this fmall Snail was dead ; as I guefTed, for want
of food, for the others of the fame fize, which were in the larger-
* Mr. Lecuweiihoek has not given a figure of this animal.
( 1^3 )
tube with the earth, continued ahve; the next day more of the fame
kind of Snails came out of the eggs, and the tliird day many more.
I often contemplated one of thcfe Snails, while adhering to the in-
fide of the glafs tube, and, with great pleafure, I faw through its fliell
(which was fo pellucid as to tranfmit the light) a part of its body not
larger than a grain of fand, and of an oval fliape, which alternately
was contracted and extended, each alternate motion being performed
in tlie fame fpace of time as is required to pronounce diftindlly a word
of four fyllables. This httle point or corpufcle, I deemed to be the
creature's lungs, and the reciprocating motion, that of refpiration.
I have formerly often difledted thefe kind of Snails found on Vines,
chufnig for that purpofe the largeft I could find, in order, if pofTible,
to difcover the manner of their generation, and whether any young
ones were to be found in them, but hitherto without any fuccefs ; and
now, almoft by accident, and with little trouble, I plainly perceived
that thefe creatures were propagated by laying eggs.
It has frequently been matter of great wonder to me, to obferve
in the fpring, young Snails of this fpecies on the Vine branches, when
I could not conceive, how they could have been bred and brought
forth fo early in the feafon. But, fince it now appears, that they are
produced from eggs, the difficulty ceafes, becaufe we can eafily con-
ceive how thefe animals may be hid in the earth all the winter in
the egg, and break out from thence, as foon as the firft warmth of
the fpring returns.
I have likewife often obferved full grown Snails of this fpecies,
whofe {hells were covered with earth or clay, as if they had been
newly dug out of the ground, and never could fatisfy myfelf as to the
caufe ; but this is alfo now accounted for, becaufe, as they muft
creep into the earth to depofit their eggs, it is natural to fuppofe that
fome portions of earth or clay may be left flicking to their Ihells or
horns. And, if any perfon fhould wonder how thefe creatures can
Xa
( i64 )
creep into the earth, I can fatisfy him in that point, from my own
experience ; for I have frequently fecn, after I had picked feveral of
them off' the tree, and not only tlirown thein on the ground, but pref-
fed tlicm with violence into the earth, by Itamping on them with my
foot, yet, in a fliort time, if their fliells cfcapcd unhurt, they would
find their way out again.
In the month of Auguft, I invited the friend I have mentioned, fo
my houfe, and acquainted him with the manner I had treated the eggs.
he had font me, and fliewed him the Snails which they had ]n-oduced,
with which he was greatly pleafcd ; and told me he had rather fup-
pofed, that the fpecies of lizard commonly called Efts would have
been the produce. The next day, he brouglit to me a very large
Snail of this fpecies, the furface of whofe fliell was covered with
moift earth, juft as if it had newly crept out of the ground ; and he
infonned me, that, while he was bringing it, he perceived it lay an
egg. Hereupon, I put this Snail into a glafs tube, about ten inches
long, and wide enough to give it full liberty of moving about ; and
within half an hour it laid feven eggs, which I perceived flicking to
the glafs, and in two hours time as many more ; but, when [ next
examined it, I found that in creeping about the glafs it had broken
them all, and in two days it died, as I fuppofe for want of food, with-
out laying any more eggs.
The fmall Snails, which, as I before mentioned, were produced
from the eggs, did not live above two or three days, and I perceived
that the fliells from whence they had ihlied were very white, but the
remainder of the eggs which had not produced any young ones,
and were barren, were of a dark colour, and of a watery appearance.
It being now demonflrated by the foregoing obfervations, that
thefe Snails are produced from eggs, the old eilablifhcd error muft
be abandoned, which thofe adopt, who dream that thefe creatures
are produced from corruption, or the decayed leaves of trees ; and
( 1% )
thence conclude, that, if fuch leaves are not taken out of gardens,
thefe Snails will be bred from them. Whereas, we ought rather, on
confidering the matter, to fay, that if the leaves which fall in autumn
are left in gardens, the eggs depofited by thefe Infe6ls in the ground,
the furface of which is covered with fuch leaves, will be the better
defended from the winter's cold, and confequently more of thofe ani-'
mals will be produced in the following fummer.
A certain Author, of the name of Kircher, having publiflied to the
world, that he had, by I>is microfcope, difcovered on the leaves of Sage
fomething like a fpider's web, woven by fome fmall infe6l, and hav-
ing thereupon founded an aflertion, that thofe who fliould eat of Sage
leaves, without wafhing them, would be poifoned, I was requefted by
fome learned friends, to examine into the truth of this aflertion.
I had many years before this time, frequently infpefted the leaves
of Sage, and always found that they were, in many places, covered
with fmall globules, but I never perceived on them any animalcules,
nor their eggs, even by the affi fiance of the microfcope.
Upon this occafion, I procured fome Sage, not only tlie green fort,
but that, which, becaufe its leaves are yellow at the edges, is called
variegated Sage. This I examined by the microfcope, and per-
ceived the leaves to be covered with many capillary or hairy parts, too
» fmall to be difcerned by the naked eye ; and fo clofely fet together,
that there was not a place in the leaves, of the breadth of an hair
without them, and, I cannot give them a better name, than capilla-
ments, or fmall hairs, becaufe, like the hairs of animals, they all ter-
minate in a fliarp point. And I fuppofe, that Kircher had ima-
gined thefe capillaments to be the webs of fpiders.
At the extremities of many of thefe capillaments, I perceived cer-
tain globules, which, through the microfcope, appeared no larger
( i66 )
than grains of fund feen by the naked eye ; and thefe globules feemed
to me to be filled with an oily fubftance. But I could not difcern
the leaft trace of any living animalcules on the furface of the leaves,
and I am certain, that, had there been any fuch, though an hun-
dred millions of degrees lefs than a grain of fand, they would have
been vifible by my microfcope.
This oil, wherein the virtue of Sage cohfifts, is produced on every
leaf of it in fuch abundance, as no one would believe, but from expe-
rience ; infomuch tiiat one can fcarcely touch a leaf of Sage, but an
incredible quantity of oily particles will adhere to the fingers.
My admiration was greatly excited, by obferving that the greater
number of the capillaments I have mentioned, were formed v\ ith three
joints, and fome, which flood on the vefl'els of the leaves, with four.
Thefe joints 1 do not remember to have feen in the capillaments ou
any other leaf, but whether that is to be attributed to my want of at-
tention, I do not know.
When Sage is dried, its leaves exhibit a whitifli colour, and that is
caufed by thefe caj)illaments, which, lying thick one on another, do,
by their tranfparency, produce that whitenefs.
This fame Kircher, in his writings, gives it as his opinion, that
Sage, and alfo Fennel, are very wholefome herbs, but, that in them is
produced a maggot, which, being inadvertently eaten, will caufe
grievous fymptoms, and even death itfelf ; and he moreover pretends
to have found by experience, that there is no plant which does not
breed fome maggot or moth ; but 1 lirely, if he had been provided with
a good microlcope, and had underltood how to ufe it in the difledtion
and examination of minute animals, he never could have broached
fuch abfurdities.
For my part, it is my fixed and fettled opinion, that no leaf, no tree,
nor any root, ever did, or ever can, produce or breed any animal en-
dued with life and motion. But, a fmall animal may lay its eggs, or
( 1^7 )
depofit its young, on the leaf or fruit of a tree, which young one,
when depofited, or when hatched from the egg, may make its way
into the leaf or fruit, and there find nourifhment to promote its
growth.
It is an eftabliflied axiom among Philofophers, that, no-
thing can come of nothing ; how then can a being or fubftance void
of motion, produce a creature endued with motion and life ? And
this is certain, that, whenever we difledl or e\amine fmall animals,
the wonderful fabrick of their bodies, both externally and internally,
ftrikes us with aftonifliment.
As to the opinion, that venomous animals do fhed their poifon on
fruits or leaves, I do not fee that this can be faid of the Scorpion, nor
that poifonous ferpent called the Rattle Snake, neither of the Spider,
nor the Indian Millepeda, becaufe, as far as I can underftand, they
have not power to hurt, by fpitting or voiding their poifon on any
©bje6l, becaufe they cannot caft it to any diftance, but thev do
mifchief, by injefting it into a wound made in the flefh. But, it is
poffible for the Frog and Toad to infe6l plants with their venom, for
I have more than once obferved thofe animals, when irritated, ejeft a
kind of water, in a ftream, from their pofteriors, which water poiTelTes
an extraordinary corrofive acrimony. This propertv was firft expe-
rienced here, by a refpe:table perfon, who, in fifliing for Jack, ufed
young frogs for a bait ; and once, while he was fixing a frog to his
hook, the animal on a fudden fcattered a little of this liquor into his
eye, which produced an excruciating pain in the part.
I have often taken notice of a large dog, who was very eager in the
purfuit of mice, which he would fwallow whole, without chewing. He
w as alfo very fond of hunting frogs and toads, and, when he had killed
them, by biting, he ufed to throw them away ; but at thofe times his
mouth was entirely covered with froth or foam, which I attributed to
the liquor emitted by them. This was mofl: particularly the cafe,
( 168 )
when he caught a toad, for then, he appeared ahnoft mad, violently
Ihaking his head, and, great quantities of frotli or Haver ill'uing out
of his mouth ; but he was accullomed, before he began to bite the
toads, repeatedly to take them in his mouth, and dalh them againll
tlie ground.
This virulent liquid in frogs and toads, they do not, in my opinion,
emit, except upon extraordinary occafions, when they are irritated,
for it is a natural inftin6l in all animals, carefully to preferve that,
which Nature has given them for their defence. So the Scorpion,
whofe weapon of defence is his iting, does, while creeping or running
.along, carry the point of the fting turned inward, towards his body,
in order to preferve it from injury.
This fagacity, and the other faculties we obferve in animals, cannot
be fuppofed to be produced fpontaneoufly, nor that, with the crea-
ture it is bred from corruption or putrefaction, but, we ought to lay it
down as a certain pofition, that thcfe faculties implanted in animals,
at the Beginning, have been, by a conftant fucceflion, tranfmitted to
their offspring ; forafmuch as we are not to fuppol'e that any new
animal, or fpecies of animals, is created at this day. In a word, the
make and flru6hire of every creature, and the powers implanted in it,
muff, in my judgment, be afcribed to God alone, the Creator of the
Unjverfe.
-^
On Wheat, and the 7nanner of its vegetation ; the nature of the feveral
component parts of that grain explained, ajid their figures defcribed
asjeen by the micro/cope.
XxLL feeds contain in them the rudiments, or firft beginning plants,
of their refpe6live fpecies ; that is, the part which, in the progrefs
of vegetation, flioots upwards, and forms the ftalk or ftem, and that,
which penetrates downwards into the earth, and is called the root.
Seeds do alfo, for the mofi: part, contain a farinaceous or mealy fub-
llance, which affords nourifliment to the young plants until the roots
arc of a lufficient fize for extra6ling fupplies from the earth, to
continue and perfedl their growth.
Among many other feeds, I have particularly examined the
grains of Wheat ; and, in them, the young plant 1 have mentioned,
before it began to vegetate, having firll either put them in
water for a ihort time, or held a few grains in my mouth,
merely to moiften the outward membranes, whereby they could the
eafier be taken off. And, having feparated the two external mem-
branes v/hich cover the young plant, I took it out from the grain, and
placed it before the microfcope, when it appeared to me to be com-
])ofed of nothing elfe than a collection of afcending veflcls, with
fome flexures or bend^njrs in them, and Ibme minute tubercles or
pimples, which pimples I conceived to be only caufed by the evapo-
rating of the moiflure.
In Plate VI. fig. i, ABCDEF, is the whole of this begin-
( 170 )
ning of the plant, magnified : EF D, are the parts or points from
whence iiot only three dirtinil roots will grow, but they are alfo the
be^^-innings of three feveral I'pires or flalks of \\heat ; for tlie minute
protuberances which appear at FA, and C D, are two diflinift j^lants :
fo that, from every grain of Wheat (which is well worthy of obferva-
tion) there will arife, not inereU' a fn.^le ftalk,b' it three diftinft ones,
which are formed in the feed itfeif And as, when fpeaking of arti-
chokes, we call the principal or uppennofl: fruit, tlie parent artichoke,
and the others chicken artichokes, fo, in the inftance before us, we
may properly name the uppeimoft plani, which appears at B, and
whofe root projecSls lower than all tlie reft at E, the pavent plant, and
the two fmaller ones, at F A, and D C, the t\\\j chickciis or fuckers.
In ojder to form a computation uf the proportionable iize of thefe
firft formed pants, I placed them befide an entire g.ain, which I
judged to be four times their fi^e both in length and tiiiiknefs, whence
it follows, that each grain of Wheat is fixty-four times larger
than the three feveral young plants formed in it, and which are to
receive nouriflnnent from it, in the beginning of their vegetiition.
I cut off a pieca of this young plant, by a tranverfe fe lion, acrofs
the part where the three vegetative principles I have defcribed arefitu-
ated, or at the place in the hgure from F to D, only to Ihew how, and
in what order, the roots (or that whith is the place or fource of tlie
roots and plants in this fee. I) do lie in refpe6l of each other ; and alio,
to point out the multitudes of vefiels formed in them.
In fig. 2. ABC, is the firft or outward membrane or covering, w hich
enclofes both the plant, and the whole circumference of the grain of
Wheat, and iscompofed of notliing but veflels extending length wile,
and which, being cut tranfverfely, appear in this membrane as tliey
are Ihewn in the figure, particularly at B, where may be feen a few
of thefe velleJs, prefenting part of their fides to the eye. The fecond
membrane or covering, is in part fliewn at D E F.
( '71 )-
The reafon why thefe membranes appear at fo great a diftance from
HI K, tlie tliree young plants, is, that this grain of Wheat was very
much dried, and therefore, in the cutting, the membranes were eafily
feparated from tlie farinaceous part, where the young plants are
placed ; but when the plants and the mealy fubftance, lying in the
fpace marked by the letters DHIKP'GD, are a little moiftened,
they very foon fwell fo much, as to fill up the whole fpace HEKI.
This, however, is the cafe in but few grains of Wheat, for, when the
young plants, and the fubftance wherein they lie, contract in drying,
the membranes which inclofe them contract likewife, they being,
generally, all clofely united or adhering together.
At the letters H 1 K, are Ihewn tlie three beginning ftalks, or roots,
of the future plants, as cut tranfverfely ; and, in thefe, the vellels
would have been much more confpicuous than here reprefented, had
it not been, that in the cutting them (although the knife I ufed was
very fharp) they were filled up or fiopped ; but, though by moiften-
ing, and then cutting them, the veflels appeared more diftindt, yet,
no fooner did the moiilure evaporate, than they contracted themfelves
in luch an irregular manner, as to be much lefs confpicuous than at
iirft. And, as to thofe which were vifible, the limner continually com-
plained, that it was impolFible for him to reprefent in his drawing, the
multitudes of (lender vellels which he law.
The fubftance wherein the young plants of W'heat are contained,
(which is very little in quantity) appears of a difierent colour from
the mealy part of the grain, by reafon, that the globules \^ hich com-
pofe it, are not, fmgly, fo pellucid, and therefore do not, altogether, ap-
pear fo white, as the meal which compofes the greateft part of
AMieat. And thefe two fubftances are divided from each other, by a
third, of a Aill brighter colour than the white meal, as in the figure
is fliewn at D G F.
If, in this figure, I had caufed the whole circumference of the grain,
Y 2
( 172 )
thus cut tranfverfely, and magnified, to be delineated, it ^vould have
occupied too much Ipace in the paper ; and therefore, I only inckided
lb much of tlie mealy part of the grain, as is exprefled between the
letters, a, D, G, F, c.
I have given afigure of the veflcls compofingthe external fliell, hufk,
or covering of Wheat, becaufe, contrary to what is generally obferved,
they do not end in a tubular fliape, but grow out into a kind of hairs.
Fig. 3, G H 1 K L M reprefents a very fmall piece of this outward
hulk, which, when ground, and i'eparated from the meal, is denomi-
nated Bran. Here, not only are to be feen the multitudes of velTels
whereof it confifls, but alfo, hov/ at their extremities, they grow out
beyond the grain, and terminate in hairy points, as at I K L.
The fecond membrane, lying within the firft, exhibits a cu-
rious fpe6lacle, on account of the tranfverfe courfe of the vellels, in a
different direction from the former; and atfg. 4, ABCDEF,is fhewn
an exceeding i'mall particle of it, wherein, though it is no more than
can be covered by a grain of fand, the wonderful courfe of thofe nume-
rous minute veflels is plainly to be feen. And, as it is truly faid, that
nothing is made in vain, we cannot fufhciently admire this, and fimilar
obje f^ s , when viewed by the microfcope.
In the fame figure, at D and E, may be feen fome of thofe globules
which compofe the mealy fub fiance of Wheat, lying within, what feemed
to me at firft, an exquifitely thin pellicle, like a third membrane,
but was, in reality, only the finer part of the meal.
I many times endeavoured to trace in the young plant, while in the
feed, the veflige or firfl formation of the ear, but all my endeavours,
even with the alhflance of my microfcopes, were fruitlefs, though I
was well afHired in my own mind, that it did there exift : at length, to
fatisfy myl'elf, if poflible, in this refpedt, I took a fmall brafs box, and
almolt filled it with that fort of white fand called fcowering fand,
onthefurfaceof whichi placed, upright, about fixteen grains of Wheat,
( ^73 )
and, after ftrewing more fand on them, to about the thicknels of tlie
back of a knife, I moiftened the fand with rain water ; and, becaufe
the weather was extremely cold, it being in the midft of winter, I car-
ried the box about with me in my pocket.
At the end of four days, fome of the grains had put forth Ihoots to
the breadth of a finger : one of thefefhoots, I cut off clofe to its root,
and, opening it, I took out the middle part of the plant, wherein, by
the help of the microfcope, I perceived fome minute leaves, and, from
their appearance, I was well alTured that the ear between them had
increafed in fize, though I could not diftinftly perceive it.
After carrying the box and the remaining grains in my pocket four
days longer, I opened it again, and, taking out from one of the flioots
that part which confifted of the innermoft leaf, immediately inclofing
the ear, I placed it before the microfcope, direfting the limner to make
a drawing of it, as it appeared to him. This is fliewn at Jig. 5,
A B C D, where A B D, is the young ear, and BCD, the inner leaf
inclofing it.
At the end of four days more, being the twelfth day, I opene^l
another of the grains, and, having Separated the 3'oung leaves a little
afunder, I was much more confident than before, that I difcerned the
ear ; this alfd I caufed to be drawn from the microfcope, as at^^'-. 6.
EFGH.
From thefe obfervations we may be fully afi'ured, that \^'armth and
water, will, of theml'elves alone, promote the growtli of plants.
And alfo, that God, the all-wife Creator of the Univerfe, does not
create any new fpecies of Things on this Earth, but that, at the Be-
ginning, he fo ordained and conftituted all things, that, his Creation
being perfe6l, the feeds of plants, when come to maturity, Ihall
produce or contain in theml'elves (however undifcoverable by us)
the part or vegetative principle of the future plant, v.-Jiich, in its
due time will be produced, and that, in all relpedts conformable to the
( m )
original plant. And this, I take to be a certain truth, which prevails
not only in plants, but in all livinpj creatures whatlbevcr.
I was clchrous to examine, whether in the ves^etation of corn, there
would be as great a number of radicles proceed from the iirftroot.as I
had obferved in grai's, and for this purpofe, I took a glal's tube, about
half an inch in diameter, and tiiree inches long; having Hopped this
at one end, I hlled it rather more than two third parts Mith dry fand,
which I moiltened with rain water, and prefled it gently together to
keep it in its place, and then dcpofited it in three grains of Wheat,
flopping alio the other end.
This glafs tube 1 Irequcntly carried in my pocket, antl in tiiree or
four days,tlie Wheat began to put forth roots. On the feventh day,
the roots were fo far grown, tliat I could mod plainly difcern them to
be compofed of wonderfully minute tubes, each of which was formed
with joints, as are to be feen in reeds or ftraws.
The diaineter of thefe roots was, as near as I could compute,
about the fixtieth part of an inch, and, at the extremities, they were
obtufe or rounding, like the ends of thole quills whicii are taken out
of the wings of birds : the lurface of them was very fmooth and
Ihining, witliout any appearance of radicles iil'uing from them,
excepting near the grain, where numbers of exquifitely minute radicles
were to be feen.
On the eiglith day, the young germ or flioot had grown to
the length of three quarters of an inch, the roots were alio lo far
grown as to reach the bottom of the tube, wliereupon 1 took
out the cork, and they then protruded themfelvesout of the tube, and
I lioped to have difcovered in them, whether there were the fame
joints in the fmall radicles as in the larger roots ; but, in the fpace of
half a minute, the moiflure in them was fo evaporated, that they be-
came contracted into irregular Ihapes.
( 17.5 )
With regard to the fize of thefe cxcefTively minute rndicles, I
made the following eftimate, as far as my eye could judge. Suppohng
the diameter of them to be as i, that of the larger root from which
they proceeded muft be confidered as 20, and conl'cquently, 4,00 of
tliefe flender radicles taken together were equal to the fize of the larger
root. Now, the diameter of this larger root being, as before ob-
lerved, the fixticth part of an inch, 3600 of thofe roots will be equal
to a cylinder of an inch diameter ; and if tliis number be multiplied
by 400, it follows, that 1,4,40,000 of the fmallell radicles are alto-
gether equal to a cylinder the fize of an inch.
This being the cal'e, we may naturally conclude, that when any
plant is pulled up by the roots, luch flender radicles as thefe, not
only efcape our fight, but mufl: almoft: all be broken off, unlefs the
earth or moilt land whicli lurroiaids them adhere to, or is taken up
With tiiem.
Aftei- thefe very flender radicles I have defcribed, had remained in
the tube three or four days, thole parts of them which did not touch
either the fandor the glafs, and were expofed only to the air within
the cavity, were lb dried up and contra6led into irregular forms,
that they a])peared like parcels of wool, or the threads of Hne linen
tangled together.
In the month of April, I took up in a field, wliich in the preceding
autumn had been fovvn with Wheat, fome of the young blades or
Ihoots, with their roots, and the earth adhering to them : and upon ex-
amining thefe, 1 obferved notliing vifible, except the largelt Ihoot or
parent plant, which was by far the largefl, and had fliot up much the
higheft. To Ihew the ,fize of this plant, I caufed a drawing to be
made of it, which is to be feen at fig. 7,,WXYZ; and in this
plant the blade being fliot up to the height of about four incites,
the joints, or knots in the fialk, were already formed, the young ear
lying at the end next to the root, at W.
( 176 )
This plant, rcprefented at fg. 7, I cut open, and took in pieces,
until I perceived the fmalleft leaves of all, which as I may lay, lur-
rounded the ear ; thefe alio I took oft", and then the ear itfelf was
vilible, which, viewed through the microl'cope, appeared as s.tjig. 8,
ABCDE. But, I did not deliver this Object to the Limner, until I
had diile61:ed Icveral of the young plants, and found, that they were
all exa6lly of the fame figure.
At the expiration of nine days from this time, I examined more of
the young blades of Wheat, but did not perceive any change in the
ear worthy of note, excejn that it was grown fomewhat higher from
the root, and that the joints or knots in the ftalk, were more plainly
to be dillinguilhed.
The ftems or Ilalks of \\'heat, which, after the grain has been
threlhed out from the ear, are denominated Straw, appear to the eye
wonderfully fmooth and Ihining, the outer coat of them being compoled
for the greater part, of ved'els incredibly flender, with here and there
a few larger ones intermixed ; the inner part is com))ofed of larger
vedels, all which I have rcprefented as nearly as pollible to Nature,
in the following figure.
Fig. 9, ABCDE F is a very fmall piece of Straw, cut tranfverfely,
and fcen throughjthe micro fcope : any pcrfon,by confidering what pro-
portion the arch, or curved external part of it, marked A F, bears to a
circle, and, comparing the fame with fo much of the known diameter
of a Straw, may ealily conceive the natural fize of the particle here
rcprefented.
ABEF, is the hark or outer coat, compoled of the vefTels
before deicribed ; GGGG, are the veflels of which the inner part for
the moft part confifts ; .they are of four, five, and fix fides, according
as, at their firft formation, their fliape is accommodated to thofe ad-
joining them.
HHHH, are vefTels intermixed with the laft mentioned ones, and
( 177 )
containing in them Oill fmaller veilels ; in thefe veni-ls I have feen the
juices (at the time the Wheat ftalks are growing) running with a
wonderfully rapid courfe ; and, through the joints or valves in thoie
veflels marked G, the juice was carried upwards, which juice was for
the greateft part compofed of globules ; and when thefe globules
came to pafs the valves where the paflage through the veflels is very
narrow, they aflumed an oblong figure, until they came into a
larger fpace, when they reaflumed their priftine globular fliape.
Fig. lo reprelents thefe afcending veflels cut longitudinally, and
feen through the microfcope, being the fame which in fg. 9, are
marked GG ; at IiII, are the valves I have mentioned, and, in tliofe
parts, the paflages through the veflels are the moft narrow or con-
fined of all.
The flalks of Wheat, are formed of none other than perpendicular
or afcending veflels, and that, in my judgment, is the reafon, why
they are furnifhed with a kind of joints or knots, at certain intervals,
in order to give ftrength to them ; and that, without fuch joints, the
flalk would not be able to fupport the ear, which is its fruit. This is
alfo the cafe with grafles, and likewife with reeds, for the lame rea-
fon ; and it alfo obtains in the bodies of fome trees. In thefe northern
parts, indeed, all trees are provided with horizontal veflels, whereby
they have a fufficient ftrength ; but, in the warmer climates, where
many of the trees have no other than perpendicular veflels, fuch as is
the cocoa-nut tree, the want of horizontal veflels is compenfated, by
numbers of thefe kind of joints, formed at fhort intervals, through
the whole length of the tree.
The farinaceous or mealy part, of which the grains of Wheat are
principally compofed, confifts of thofe minute globules I have before
noticed. Thefe globules are, fmgly, tranfparent, and lie clofely
compa6led within a kind of membranes, fo exquifitely thin and tranf-
Z
( 178 )
parent, timt, in fonie places, their texture is not to be difcerned. A
very fmall particle of one of thele membranes, as it ai)peared upon
the grain being cut longitudinally, is ihewn ^t fg. ii, EFGH;
within thele membranes the globules of meal are inclofed, as it were,
in cells ; and, at H, fome of thofe cells are reprelented, filled with the
globules of meal : the natural fize of this figure, is no more than can
be covered by a common grain of fand.
The globules of meal, are of ver}- different fizeSjforae being more
than an hundred times larger than others, and fome fo fmall, that they
almolt efcape the view of the microfcope. In order to gi\e the reader
fome general idea of their minutenefs, I took one of the larger grains
of that fort of j^ellucid fand, ufed in fcowering or grinding ; this grain
of fand, together with fome of the globules of meal adhering to it, I
caufed to be drawn from the microfcope, as at Jig. 12, ABC D E. In
the fame figure, FG H denote a fmaller grain of land adjoining to the
former. I K L M are Ibme of the larger and fmaller globules of meal,
lying near the grains of fand.
I had at firfl: imagined thefe mealy particles to be quite globular,
but I afterwards found, that I had been millaken in that refpe6l; and
that they were not perfecl fpheres, eacli of them having a kind of
creafe, chink, or indenting, like that Vv'hich we fee in the grains of
Wheat, which had at firfl efcaped my notice, partly from the extreme
minutenefs of the particles themfeh'es, and partly from their different
pofitions with refpeft to the eye.
Upon viewing thefe mealy particles, and the indentings in them I
liave mentioned, I began, not without wonder, thus to reafon with
myfelf. Certainly thefe particles of meal were not compofed by a
concretion or colle6lion of ftill fmaller particles, placed fide by fide,
as is obferved in fome liquors, fuch as wine and beer, whofe particles
coagulate, and grow together in maffes, which, in the former we call
dregs, and, in the lattertartar ; but the particles of meal muft beformed
( 179 )
in another manner, that is, not by coagulation, but by groNvth. And
the membranes which indole them in cells, mufl be provided with fo
many veins or vefiels, that every particle of meal may have its fepa-
rate vein, whence it derives its fubflance and increafe, in like manner
as the eggs of fifhes are nouriflied by a ligament or vefTel, which is
obf'erved not only in the larger fifh, but in thofe very minute
eggs which are feen in vaft numbers on fhrimps. Now, if the parti-
cles of meal, which, thougli not ftri6tly fpherical, may yet be termed
globules, had ]:ot acquired their growth in that manner, it fliould
leem that they could not obtain that globular figure.
Vv'hen we confider tlie tranfparency of ever}- one of thefe globules
of meal, wc may well exclaim, How wonderful is this formation,
and how clofely compacrted mull be the fmalleft particles of which
each globule is compofed, to give it that tranfparency !
I next proceeded to examine, whether thefe particles of meal might
not be globules, inclofed in a certain thin membrane, as we fee is the
cale with all feeds ; but I cannot be confident, that I ever did bring
this to m}^ ocular demonftration. I then broke the globules in pieces,
and imagined that I faw fmaller ones inclofed in them, but herein I
found myfelf miftaken, for, thofe globules which I law fcattered
among the pieces, were Ibme of the very fmalleft mealy globules,
collected in fmall parcels.
I then u'ed my utmoft endeavours, to difcover the internal hidden
make of the globules of meal, wherein, at length, to my great fatif-
faftion, I fucceeded. I placed fome of them on a clean glafs, and
mixed them with a very fmall drop of water : when they were by
this means feparated, I poured on them two more drops of water,
and brought the glafs fo near to the fire, that in the fpace of a minute,
the water was all evaporated. Then, bringing them before the mi-
crofcope, I perceived, that their globular form was changed into flat
fliapes, of different fizes, according to the different magnitudes of the
Z2
( i8o )
globules tliemfclves. Many of them had a little rifiiig in the middle,
which I judged to be that part, through which they had received their
prowth and increafe.
This convinced me, that the globules of meal in Wheat, are
covered with a fi^in or fhell, in like manner as the Wheat itfelf,
for, by the compreflion and flattening of the figures in the abo\e
e .periment, they would have been dillolved or fcparated, had they not
been confined by fome fuch covering. I then concluded, that the
chinks, creafes, or indentings I have noted in thefe globules, were in
thofe parts where their fkins had a kind of feam or joining, fo that
when warmed and moiftened, their fkins had burft open at tiiofe
places, and the globules fubfided into a fiat fliape, as before menti-
oned.
From this obfervation, I was induced to examine the grains of Wheat
themfelves, in order to inveftigate, how, and for what purpofe they
were formed with thofe indentings, chinks, or creafes.
For this purpofe, I cut pieces off' the grains, by a tranfverfe fe6iion,
and examined thofe pieces by the microfcope, when I found, that the
fhell or hufk takes its courfe into the middle of the grain, and, on each
fide, returns in a curve or bcuding to the chink, by which means, the
hulk, when tlie grain fwells upon being, moifiened, can expand itfelf
into a greater fpace.
Hereupon I was led to confider, that, wliereas fowls, turkies, par-
tridges, pigeons, and other birds who feed on corn, cannot with their
bills, break or grind the grains of Wheat, P.ye, and Barley, but take
them into their liomachs entire, where, by rcafon of the hardncfs of
the hufks, they cannot be broken ; feeing this, I fay, I cunfidered,
that thefe kinds of grain mufl liave been fo contrived and formed by
the all-wife Creator, that, without the hufks being broken in pieces
and digefted, their contents may be diilolved : which is thus per-
formed, namely, that by the moillure and heat in the ftomachs of.
( ^8i )
thofe animals, the outward huflcs, or (liells, may be expanded and
burft open, and the meal which they contain, having by this means
-te pailage opened to quit its covering, may be diffolved, digefled, and
converted into nutriment.
To inveftigate this more fully, I took a glafs tube, about the fize of
a finger, and clofed at one end ; into this I put fome grains of Wiieat
and Barley, with a fufficient quantity of water, and then applied fo
much heat to it, as, in a fliort time, made the water boil. Then, upon
examining the Wheat and Barley, I obferved, that their hufks, which
before, had been as it were clofely folded or clofed together, were not
now, broken or torn afunder, but, in the places where the grains had
been contrafted and turned inwards, the parts had now receded ei-
ther way, caufing the hulk to gape open, fo that, in fome of the
grains, a part of the meal was vifible, and in others the whole con-
tents were laid open. Some of the grains of Wheat, however, I ob-
ferved, which hadfwelled to three times their original fize, the hufks
remaining entire.
After this, I examined the dung of fome hens, which, in the time of
a deep fnow, were kept fliut up in a coop, and fed with nothing but
"barley, which, it is well known, they fwallow whole. And, in the dung
of thefe fowls, I was much furprized to find nothing obfervable, ex-
cept a great number of pieces of the hufks of barley ; and I was at
a lofs to comprehend, how fo great a quantity of meal as thofe hufics
had contained, could have entered into the bodies of thefe fowls, con-
fidering that they were all full grown.
Farther, I infpefted the dung of many fparrows, in which I found
a great number of very fmall hairs, clofely compa6fed together, in
a kind of regular order; together with many fragmcn^^s of the hufks
of Wheat and Barley. I at firft wondered what thefe hairs might be,
till 1 recolleded the hairy or reed-like parts at the extremities of the
grains of corn, which I have before defcribed, and found thefe to be
( i82 )
the Uxme, for, in them I could perceive a kind of flrcak or hollow,
whicli is oblervable on thofe iiairs. Thcfe ^parro^vs, i undcrftood,
during this feafon, when the ground was every where covered w'ltki
{'now, fought their food in the corn market, where they picked up
the grains which, in handling and \icwing the corn, had fallen to the
ground.
In order to exhibit to the eye, the manner in which the hufks of
Wheat arc folded or clofed together, I caufcd a drawing to be made
from the microfcope, of a piece cut from the grain tranfverfely ; but
firft, to lliew the pofition of the chink or indenting, I ordered the lim-
ner to draw a figure of the entire grain, in its natural fize. This is
fliewn at fig. 1 4, wherein the fifllire, chink, or indenting, is denoted by
the letters N O. The line P O, indicates the part from which, with
a very fliarp knife, I cut feveral dices.
Fig. 15, A B C D E, reprefents a part or flice of the hulk of Wheat,
inclofing the meal, cut off as above mentioned, and viewed through
the microfcope. A, is the part near that place in the grain, where
the young plant is fituated. GHFKI, are the two bendings in-
wards of the hufk, in a kind of circular courfe, the intent of which
formation doubtlefs is, that, when the grain fwells upon being
moiftened, the hufk may expand itfelf, and ftill preferve the meal in
its place : and by infpeclion of the i)art F, it will be feen, that the
hufk is not clofely united where the two bendings or flexures meet,
to the end, that when the meal expands itfelf ftill more, the two
fides of the hufk may recede from each other, and produce an open-
ing at that place.
I have already defcribed the fize of the globules of meal, by com-
parilbn with larger and fmaller grains of fand. I alfo caufed fome
of thefe globules to be drawn, as feen through a microfcope of very
great magnifying power ; firft, to fliew more diftin6lly that they are
formed with a chink or crevice on them, next to exhibit to view the
( 183 )
fmaller globules, mixed with the larger, and finally, how the chink
or crevice appears on them. Thefe are Iliewn ^^fig. 16^ LMNOP
O R.
I have frequently repeated the experiment of placing a portion of
thefe globules of meal, no larger than a grain of fand, upon a clean
glafs ; and, after pouring a drop of water on them, brought it to the
fire. After the water and globules Vv'ere heated, and the moifture was
evaporated, the globules allumed a flat fliape, very like that of cakes,
^vhich is reprefented in fig. 17, STVW. Mofi: of thefe had a little ri-
fing in the middle, being the place, as I before mentioned, where, in
my judgment, they were fupplied with juices in their growth. And I
have often feen the very fmalleft of the globules undergo the
fame alteration in their fliape as the larger ones. In thefe obferva-
tions I found a portion of meal, no larger than a grain of fand, mixed
with a fmall drop of water, fully fufficient to exhibit the change of
fliape before noted ; for, if more of the meal is ufed, the particles lie fo
confufedly heaped on one another, that they cannot be diftinftly feen,
and, it is fcarcely to be conceived, that a portion of meal, no larger
than a grain of fand, fliould confifl of fo many particles as are pic-
tured m fig. 17.
I have often examined a fmall ])iece of bread, taken from a loaf
made of fine flour, after the hufk or bran had been taken from it.
The particles of meal in this fmall piece of bread, appeared very much
like thofe reprefented mfig. 17, with this difference only, that the
particles in the bread, lay much more irregularly, and appeared more
mis-fliapen, Vvith ragged points and rifmgs; a true reprefentation of
all which is to be feen at fg. 18, A B C D E.
• 4-
ADDITION, BY THE TRANSLATOR.
WHOEVER pciuCcs Mr. Leeuwcnhock's Works, will find difplayed in
them niucii found philofophical knowledge, of which funic inftanccs appear
in the preceding JLffay. Thel'e I fhall quote, in order to explain tholcparts
in them, which may appear difficult to fome of my readers. In page 171, the
author tells us, that the fubflancc inclofing the young plants of Wheat, ap-
pears of a different colour from the meal)' part of the grain, by rcafon that
the globules which compofe it are not, fingly, fo pellucid, and therefore do not,
altogether, appear fo white, as the meal ; and in p. 179 he reflefis, with admi-
ration, how clofely compared mult be ilie fniallell component particles of
the globules of meal, to give them that tranfparency. To thofe, who are not
conyerfant in optics, it may appear ftrange, that the moft tranfparent bodies
have the fmalleft pores, and, that a collc6tion of fmall tranfparent globules
fliould altogether exhibit a white colour, but this is according to the cfla-
bliflieddo8rine of light and colours, of which Mr. Leeuwcnhoek appears to
have been fully informed.
As to the firft, Sir Ifaac Newton has flicwn, that it is not the largenefs of
the pores of bodies which makes them tranfparent, but the equal dcnfity or
continuity of their parts; which, he fays, appears from hence, that all opake
bodies immediately begin to be tranfparent, when their pores become filled
with a fubftance of equal or almolt equal denfity, with their parts : thus pa-
per, dipped in water or oil, linen cloth deeped in oil or vinegar; and other
fubftances, foaked in fuch fluids as will intimately pervade their little pores,
become more tranfparent than before.
As to the fecond, white being a compofition of all colours, a colleBion of
tranfparent globules, which, from their furfaces reflcft the light in all direfti-
ons, will produce whitcnefs by that refleBion. This is feen in the froth on
liquids, and particularly foap-fuds, which is nothing but a compofition of
jninute globules of water, made tenacious by the foap.
Of the Cocoa Tree, and its Fruit, commonly called the Cocoa-nut.
I HAVE faid, that flraws, reeds, and many other ftalks of plants,
were formed of none other than perpendicular veflels, whereas the
Hems or bodies of all trees growing in our climate, at leait as far as
I have ever underftood, are likewife provided with horizontal vef-
fels ; the ufe of fuch laft mentioned vefiels being, in my judgment,
to convey the nutritive juices to the exterior parts of the tree. Now
thefe horizontal velTels impart fuch ftrength and firmnel's to tlie tim-
ber or trunk, that the moll fpreading trees are enabled to refifl: the
violence of the wind.
But ftraws, reeds, and other (talks which are deflitute of horizontal
veflels, require ibme other means of fupport ; for, if all the veflels,
from the eartli up to the fummit of the ftalk, were difpofed only in
uninterrupted parallel lines, tli.e flialks would be fo weak and flexible,
that they could neitiier refifi; the wind, nor be able even to bear the
weight of their own fruit. Therefore, thefe kinds of ftalks, are
ftrengthened by a fort of joints or knots, at intervals, which prevent
the over much bending of the ftalk ; and the joints are placed at
fuch diftances that the ipaces between each will allov/ the bending,
only fo much as to recover itfelf.
What has been faid of the joints in flalks growing in tliefe regions,
I confider as applicable to fome forts of trees in the Indies ; and,
upon feeing fome of thofe hidian trees defcribed in drawings, I im-
mediately concluded, that the Cocoa Tree was of the number.
Aftorfevcral endeavours to obtain a i'pecimen of this tree. I at length
A a
( 192 )
j^rocured from a certain fea captain, a piece of one, about a foot long,
and ten inches in diameter. The bark of this wood was found, but
the wood itfelf fo decayed, tiiat it crumbled into powder under the
finders, excepting only a very fniall part. The capillary or hairy
parts which run length wife on the infide of the bark, were tolerably
found, but they fcparated from each other, as eafily as if they had
never been firmly united, which inade me fufpe6l, that, if there ever
had been any other parts to connedl them, they were decayed.
I j)erceived that thefe capillary or hairy parts, grew out of
the bark, and that many of them were divided into two ; and I alfo
perceived in each of thefe capillaments many veOels. Among thefe
capillary parts were otliers, fome firm and folid, others in the na-
ture of velVels, but the greater part of them much decayed.
Thefe capillary parts, were covered by the external folid bark,
which bark .was, in fome few places, thicker than in others, but, at
the knots or joints, the bark was remarkably thick and folid.
This bark, cut tranfverfely, I examined by the microfcope, and
found it chiefly to confill of roundifli threads, about the tliicknefs of
an hair, and thefe again compofed of oblong filaments, hollowed on
tlie infides. Many of thefe latter did not take a firaight, perpendi-
cular courfe, but turned inwards towards the body of the tree.
Farther, I obferved, intermixed among them, a kind of fubfiance,
confiding of roundifli globules, conne6led in a fort of regular
order. Thefe parts, compofing the external fubftance of the
tree, were fo clofely united together, that it might be thought the
tree had not any bark on it. From all thefe obfervatioi-ks, I was led
to conclude, that this tree receives its growth and increafe from the
bark alone. And 1 perceived certain roundifh parts, which feem^
ed to iffue in a right line from the bark inwards, as if they were de-
figned for no other ufe, than to convey the nutritive juices in that
diredlion.
( 193 )
If, however, we could be fiirniflicd with a piece of this tree, cut
while ahve and growing, our obfervations might be much more ac-
curate. And, indeed, I was not witliout fufpicion that this piece of
wood had been cut from a dead tree, though one of the feamen af-
I'ured me, that the decay which I luive before mentioned, liappened to
it on board the fliip.
In order to place before the reader's eye the form of the joints
knots, or bands, whereby the body of the Cocoa-tree is ftrengthcned,
and which as it were, furround it tliroughout with a fort of girdle, I
caufed a drawing to be made of this piece of wood, on a contra6led
fcale ; from which drawing will be feen, how firmly thofe trees,
which have no horizontal velfels, are ftrengthened by thefe kind of
bands, furrounding them in an oblique direction.
Li Plate \:\.fg. 1 , A B C D E F G H I K L M, reprefent this wood
drawn fmaller than the natural fize. C M, C L, D L, E K, F K,
F I, indicate the pofition and courfe of the knots or bands, that is,
that they do not go in a ftraight line round the tree, but fometimes
approach to, and fometimes recede from, each other, whicli approach
and receding are fliown at K L. And, this oblique courfe of the knots,
bands, or cin6lures, contributes more to the llrength of the tree, than
if they encircled it in the form of hoops.
By cutting and examining tliis wood, in the manner I have de-
Icribed, I fully fatisfied myfelf in the particular wherein I wiflied to
"be afcertained, namel}^ that the Cocoa Tree has no horizontal vef-
fels. And there is moreover a circumftance to be noted in thefe
kinds of trees, that they have no branches except at the very tops,
^md therefore, are not fo ftrongly a6led upon by the ibrce of the
wind. Nor are the branches which they have, perennial, but tliey
every year fall oft, and are replaced by frefh branches, which grov/
on the tree at the fame time with the fruit.
I alfo cut tranfverfgly a piece of the wood, in a part where it was
A a 2
(^91-)
found, in order to fliew, as accurately as pofiiblc, tlie inake and tex-
ture of this wood, when viewed by the inicrofcopc.
Fig. Q, OPQR, reprefents a very fmall particle of the Cocoa
wood, cut tranfverfely, and magnified, wherein are to be fecn fix of
the larger of the perpendicular vefiels, two of which, furrounded
by a great number of fmaller veflels, are to be feen at T T. Of
thefe larger and fmaller veflels, the capillary or hairy parts I have
mentioned, and which are very tough and ftrong, are compofed.
But thefe vefiels do not all afcend in an exa6t perpendicular direc-
tion, but creep upwards in a kind of oblique courfe, one among ano-
ther, by which pofition they contribute to tiie flrength of the tree.
And when one of thel'e vefiels or threads divides itfelf, each divided
part, though it prefents tlie figure of a fmaller filament, is yet in
truth a perfe6l vefiel. Theie fmaller vefiels, intermixed with
the larger ones, I have caufed to be rejjrefented in the drawing.
Thefe larger vefi"els feem connefted together by a kind of
veficles, whicli, I imagine, while the tree is alive and flourifiiing,
are filled with fome kind of liquid. Thefe veficles are not difpofed
in any orderly or proportionate manner, but in fome places they
may be feen heaped together to the number of five and twenty, and
in other places, between two capillaments, will be found only a fingle
veficle.
Such of thefe capillaments as are next to the bark of the tree,
are exceeding fmall, in comparifon of thofe nearer the middle ;
and, to exhibit them to the reader, I cut ofi' a piece of the wood
next to the bark, and caufed it to be drawn from the microfcope,
which drawing is copied iitjig. 3, ABC D. In this figure, A D is
an innermofi: bark next the w'ood, being a very thin fkin, and the
capillaments next to it are the I'malleft of all, whereas tliofe more
inwards, grow larger and larger. But, though thefe innermofi cap-
pillamems are the largefl, they are fiiU compofed of thofe exquifitely
( 195 )
thin and hollow filaments I have mentioned, the hollows or cavities
in which I have caulbd to be reprefented by a fort of points or do's.
The biack fliade in this figure, denotes minute veflels furrounding the
others, which by reafon of their exceeding fmallnefs could not be
reprefented in the drawing.
Thefc veficles, which I have mentioned to adhere to the cap'lla-
ments, as they appear, when cut by a firaight fection, are Ihewn at
Jig. 4, EFG H. In thefe veficles there appeared fome fmall parti-
cles, concerning which, however, I could not pronounce any thing
with certainty.
After I had made the preceding obfervations, I received from a
friend who obferved how defirous I was to inveftigate the nature of
the Cocoa wood, a piece of that wood which he had procured from
the ifland of Curacoa. This was feven inches in diameter, and about
four inches long : in the middle, it was compofed of the before men-
tioned larger capillary parts, but, on the outfide, and about an inch
from the furface, it was fo hard, that in attempting to fplitit, I broke
a fieel wedge in pieces, and I do not remember ever to have met
with fo hard a wood.
Between the bark and the folid part of this wood, I law fome
capillary parts creeping along, and which v,'ere of the fame nature
as thofe pi6lured mjig. 1, between G and N, and thefe capillaments,
I was informed, are made ufe of to be twifl;ed hito ropes and ca-
bles.
I obferved, that wherever the knots or bands in the bark ap-
proached each other, as at F K, there the capillaments grew out of
the bark : fometimes I obferved one or two branches rife out of one
of thefe capillaments, and thefe again fubdivide into I'maller ones,
hollow within, and which capillaments I judged might in time unite
and form velfels of the fize pictured mfg. 2, at T T. And if fo, it
follows that the Cocoa tree receives the addition to its bull< from ther
( ^9G )
bark, contrary to what we fee in the trees of this country, the bark
of which receives its increafe from tlie wood.
I alfo cut tliis wood from Cura^oa tranfverfely, and examining it
by the microfcope, I found it to agree in all refpedls with that repre-
fented in Jig. 2, with this difference onl3^ that where this wood was
harder than the former, there the capillaments werefmaller, and alfo
exceedingly tough.
But as the veficles in the former wood, v/hich are reprefented
at fig. 4, EFGIi, were in this latter much harder, and alfo
fmaller than the former, I cut fome of them b}' a ftraight fe^ion, and
caulbd a very fmall particle of them, when magnified, to be drawn
from the microfcope, which is to be feen in Jig. 5, at 3LM2,
Thefe veficles, I perceived were of a more firm and folid texture,
than thofe in the other piece of wood, and they had in their centers
a black fpot, which was a fign that they had had a cavity in them :
fome of thefe veficles 1 cut in fuch thin flices that they appeared
trail {'parent.
While I was bi'fied in this part of my invcfligation, I happened to
cut one of the afcending veflbls, which mjig. 2, is denoted by T, but
which here is fliewn between I K 3 2 N. And, though the fmaller
veHels furrounding it, could not, by reafon of their nVmutenefs, be
otherwife exprefled, than by ftraight lines, yet this larger velTcl
plainly appeared to be formed of a kind of annular parts, running
round each other in a fort of fpiral form. And, though I had ob-
lerved this formation of the veflels in many otlier forts of wood, yet
I could not till now, venture to fay, that thel'e veflels were formed in
that manner, becaufe I had hitherto loft my time and labour in en-
deavouring to dilfedl tliem accurately. But now in tliis objedt,
where the veffel fpread or o])ened itfelf a little, at tlie place marked
N, I plainly law the fpiral formation, ^^ hich difcovcry gave mc grea|;
ploafurc.
I proceeded ftill farther in the examination of this larger vefTel,
and I found it to be compofed of, at leaft, five fmaller ones, which
were placed in regular order, befide each other, and each feverally
formed in the fpiral manner I have mentioned. All thefe are fhewii
in /ig. 6, O P, and in the fame figure, at P Q, is to be feen the part
which I before mentioned liaving feen, as defcribed in^^. 5, at N.
This circuitous figure of tlie veffels, may be exactly compared to a
brafs wire, twilled round a fmall rod, and the fame kind of formation
I have frequently, as I have before mentioned, feen in other woods.
And even in a ftraw I once obferved, by the microfcope, one of its
larger veffels to be formed, much in the fame manner as this I have
defcribed at O P. And, when we confider the fubje6l, we cannot, in
my humble opinion, conceive any form fo fuitable for thofe veflels to
raife the juices upwards.
The fame gentleman from whom I received the lafl: mentioned
piece of Cocoa wood, fent me alfo two Cocoa nuts, inclofed in their
feveral fliells or coverings. From one of thefe I cut fo much of the
outer covering, as to exhibit the inner Ihell to view ; and I caufed a
drawing to be made of both, on a contracSled fcale, which is to be
feen a.tjig. 7, A B C D. The diameter of this external cafe or cover-
ing was nearly five inches and three quarters, meafured by the fcale
B D, which is five inches Ions.
This external hufk or Ihell fo firmly adhered to the inner one,
being conne6ted to it by multitudes of veffels, that I found it a
work of confiderable labour, to tear it off. The inner fhell was
four inches in diameter, and, having cleared it from all the vefiels ad-
hering to it, I replaced it in the half of the cafe or hulk, as is to be
feen in the drawinsT.
I have often been told, that the filaments of which this external
hufk or bark confifts, are of fuch a length that they are twilled into
cables, and alfo wove into fail-cloth. 1 proceeded, therefore, to exa-
( ^98 )
mine tlie texture of this hufk or bark, when I found, tliat not a tenth
part of it confilled of thofc filaments, but that, from them proceeded
a certain fubftance, like a colle6lion of veficles, which veficles, while
the fruit was living on the tree, had been filled with juices, in like
manner as thofe parts which, colle6led in great numbers, from the
fubfiance of the pear called the Sugar pear, do proceed from the
veins or velTels in that pear.
To convey a true idea of the formation of this external coat,
hufk, or covering, of the Cocoa-nut, I caufed a drawing to be
made from the microfcope of a very fmall piece of it, as is to be
I'een in fg. 8, M N O P O. Here, N P O denote the capillaments,
which may more properly be called veflels ; they are each inclofed
in ii larger one, which larger one is compofed of numbers of minute
velTels.
It is well known, that all fruits, and even the fmallefi leaves, are
covered with a fkin, which, that it may prevent the exhalation of the
juices, is of a very clofe texture. This external coat or hufk of the
Cocoa-nut has that kind of ficin, which, as it appears through the
microfcope, is exhibited in^^. 9, ABCDEFGH, where are fliewn
ns exadtly as may be, the vefTels running along this fkin, and con-
ne6led with the internal part of the hufk, as for example, as B D E,
A E, and H G. A branch proceeding from the velTel B E, is repre-
fenled at C D.
In the fhell of tlie nut, pictured ?i\.fg. 7, there are three parts
fomewhat rcfembling eyes, two of which point towards each
other, the third contains the young plant, which, when the kernel
begins to \egetate, flioots out through that cavit3^ And this young
plant in its vegetation receives nourifhmcnt from the kernel, through
thclJ2 perforations I have called eyes, until it is able to draw its nou-*
rilhment from the earth, and this, without there being a necefllty
for the Ihell of the nut to break or open. The vegetation of the
( ^99 )
C'lefnut is performed in tlie lame way, contrary to wliat is obferved
in tlie leeds of nuts, plumbs, and the like, the Ihells of which, as the
vegetation of the kernel advances, divide and open themfelves.
Moreover, I cut off I'everal pieces from the hard fliell of tlie Cocoa-
nut, fome of them longitudinally, fome tranfverfelv, in order to Iliew
tjie texture of it, as feen by the rnicrofcope. This Is reprefented at
fg. lo, IKLMN, in the inner part of which is a vein or veflel di-
viding itCelf into many fmaller ones.
I next proceeded to exajnine a thin membrane or fl;in, which
lines the infide of this hard fliell. An incredible number of veflels
^^■hich may be feen by the naked eye, are difperfed tlirough this
membrane ; the hard ihell is of a dark colour, vere:ine towards a
black, and the membrane of a faint afli colour. I have often placed
pieces of this membrane before the microfcope, and could not,
without admiration, behold the almoll incredible number of fmall ob-
long parts therein, which were heaped one on anotlier, in fuch vari-
ous manners that I could not conje6lure for wliat ufe they were de-
figned ; but they all conlifted of fpiral parts, fuch as are deicribed in
Jig. 6, at O P. Thefe parts were fo exquifitely flender, that upon
comparing them with a vein taken from the breafl of a flea, which I
had Handing before a microfcope, I found that the vein (which was
alfo of a fpiral form) was about four ti nues as large as thefe comix)-
jieiit parts of the membrane, and I could not futticiently wonder at
the multitude of thole fpiral parts,
I have alio often placed before the microfcope, thofe capillaments
which in breaking the rtiell I found adhering to it by one of their ex-
tremities, merely for the pleafure of contemplating the objecl:; for, a
capillament no larger than an hair, would be feen to conhlt of twenty
filaments, the fmalleil of which I judged to be Id's than the thread
Ipuii.by the filk worm. So that, if we would compute the whole
Bb
( 200 )
number of tliefe filaments in a fingle nut, wo muR not reckon then*
by thoufands, but by hundreds of thoufands.
That which is the kernel of this nut, and is commonly called the
Cocoa-nut, is a very white fubflance, about half an inch thick, clofely
joined to the whole in':erior part of the fnell ; the remainder of the
cavity contains a watery juice, which is what I never obl'erved
in any other feed, when come to maturity. For nuts and chefnuts
are entirely compofed of folid parts, which we call the kernel,
though before they come to maturity the matter inclofed in them,
is no n:iore than a watery and flimy fubftance.
Upon this head, I reafoned with myfelf ; that before the inward
fubftance of the Cocoa-nut is full grown and ripe, the fliell becomes
harder than thofe of any fruit known in the northern climates ; and
I concluded that when the fliell is grown perfedlly hard, it cannot be
afterwards increafed in fize, nor can the kernel it contains receive
ajiy addition to its fubflance : and therefore, that part of the nu-
tritive juice which is of a Avatery nature, and cannot be converted
into kernel, mufl; remain in the center of the nut.
I afterwards fell into converfation with two mafters of fiiips, who
had vifited both the Eafl and Wefl Indies, and had been often em-
ployed in collefting Cocoa-nuts. They informed me, that when the
fhells of the nuts were fo foft that they could be cut with a knife,
there was nothing to be found in them except a lymph, or thin liquor,
of a very pleafant tade, which information confirmed me in the
opinion 1 have before related.
At another time, upon a different invefligation of the Cocoa-nut,
1 prelTed from the pulp or white fubflance of it, fuch a quantity of oil
as fixed me in aflonilliment.
After this, upon opening a Cocoa-nut which I had kept for the
fpace of feven months in my cabinet, I obferved thofe three foft
places in the fhell which are called eyes, and from one of which the
( 201)
young plant flioots forth, to he covered, and, as it were, fealcd up,
with a fubftancc like rofin or pitch.
To give a more pcrfcvlt idea of the nature of the Cocoa-nut or
hernel, after I had bored the Ihcll near the place v,'here thole
parts I have likened to eyes are fituated, and poqred out the juice
contained in the cavity, I broke away the fliell fo far as was fullici-
cnt to flicw tlie infide of the nut, that it might be exprcHed in a
drawing.
Fig. 11, O P O R, reprefents the Cocoa-nut or kemelasit appears,
inclol'ed in the iliell, Vvhich fliell is denoted by PQR. At P R, are
ibme of th.ofe capillaments, which in great numbers, are found
united to the fliell, and, as they are in fad:, no other than vefiels
deftined to convey the nutritive juices, they penetrate into the inte-
rior part of the Ihell, and there impart nourilhment to the fruit.
Farther, many very fmall ved'els take their courfe through the
hard fliell, and thefe, as I found by the microfcope, were compofed
of other vefiels incredibly flender, the fmalleft of which were of
the fpiral formation defcribed in^^. 6, O P.
STV, denote the nut itfelf, properly fo called. WXY is a
-cavity within it, which contains the fap or juice I have mentioned,
which is very pleafant to the tafte, and of a nouridiing quality. A
drop of this juice I put into a very clean glafs, in order, Vvhen
the watery parts of it were exhaled, to examine the remainder, and
-therein I did not find any faline particles, but it had the appearance
of a fyrup, which did not evaporate, being more of a fixed nature.
This kernel is conne6led with the hard fliell by infinite numbers
of vefiels, and on the fide next the Ihell is alfo covered with a tliin
Ikin, through which multitudes of vefiels take their courfe ; they
are of the iame fpiral figure as before mentioned, and lye clofe to-
gether, and they are not much thicker than the hair of a man's
Bb 3
( 202 )
beard. Whence it appears that the kernel is formed and nourilhed
from thefe very flender veflels.
Upon examinhig this nut or kernel by the microfcope, I found that
its fubftance is not, like other feeds, inclofed in I'mall membranes,
but confifts of multitudes of minute tubes, which take their rife
from the hard fhell, and reach to the cavity, within the kernel, where
the juice I have mentioned is collefted. They are not all of an equal
fize, nor are they of a round figure, but rather of fix fides, whicli
Hiape is well adapted to permit their lying clofe together and in
regular order. Some of thefe are turgid with a certain fubftance,
which in part evaporates ; others of them contain glx)bules which I
judged to be chiefly filled with an oil.
Thefe fmall tubes, which \nfig. 1 1 are to be feen at W, I cut tranf-
verfely, and caufed a drawing to be made of a very fmall portion, as
viewed by the microfcope, which mfig. 12 is exprelled by A BCD :
the fmall points, or dots in this figure, denote fome very I'mall parti-
cles, which' I obferved in thefe tubes.
Moreover, I caufed a drawing to be made of that part of the nut
or kernel, where I judged the young plant to be fituated, in the
fliape it exhibits when feen by the eye alone, without the microfcope;
This occupies but a very fmall part of the kernel, and is fituated in a
part where its fubftance is thinnefl. A drawing of this, of the na-
tural fize, is to be feen atfg. 13, ABC DEF, and HEG is the part
which in my judgment contains the entire 3'oung plant.
From this part I cut fome very thin dices at that end of it whicli
hyjig. 13 is neareft to the letter E. For I was defirous to examine
whether any thing would there be found bearing any fimilitude or
refemblance in figure to the future ftem of the tree. Some of thefe
flices I placed before the microfcope, and caufed a very fmall portion
thereof to be drawn, that it might not take up too much fpace in
the paper. This is reprefented in fig. 14,, at EFGHI. In this
( 203 )
figure TEF denote the fkin or covering, inclofing what I take to be
the plant. The remainder of the figure repreients afcending vedeLs
and which, as far as I could dilcover, were filled with an oil. Thofe
parts which appear like larger velTels, and are indicated b}^ K K K,
were fhining and tranfparent, and were.compofed of other vefl'els, fo
Imall as to exceed all belief.
Upon cutting this part marked HEG, not far from the end, next
H, I was aftonifhed to find that this was not, wholly, the young plant,
but chiefly its cafe or inclofure, the young plant itfelf, which was
contained in it, being not much larger than a grain of land. One
of the pieces thus cut off I placed before the miciofcope, and deli-
vered it to the limner, dire6ting him to make a drawing of the ob-
je6l which prefented itfelf to him, as nearly as it was pofiible for his
art to imitate it. This flice, which had been cut lengthwife, tiius
depi(?ted, is Ihewn at^^^. 15, IKLM.
I took great pains to examine many Cocoa-nuts before I could be
certain that whatinj?_§-. 15, is marked I KM, was really that part of tlie
young plant which would penetrate downwards into the earth, and
become the root, and that what is defcribcd at KLM was that part
which would grow upwards into a tree ; but I am now fatisfied
that this is the cafe, and that the parts lafl mentioned are the leaves,
which in this young plant are already formed.
I many times endeavoured to feparate thefe young plants from the
integuments inclofing them, but always in vain ; becaufe that part
which hifg. 1,5 is denoted by I KM, firmly adhered to thofe inte-
guments. All I could do therefore, was, to cut the young plants in
pieces by a longitudinal fe6lion ; in doing which, however, it often
liappened, that the objedl prefented three or four fhapes to the view,
by reafon that I had fometimes cut the plant dire<511y through the
middle, and fometimes on one or the other fide. To fet this alfo be-
fore the reader, I have given two drawings of the pieces lb cut.
( 204. )
oinittine; only the iiitefjuinciits or circumjacent parts inclofing
them.
l1.ie firrt is, of a phuit which I had, as I believe, cut exa6lly
tln'ongh the middle, and it is fhewn ^^fg. 16, N O P O. Here, NOQ,
is the part which would become the root, and OPQ, that which
Avould grow upwards into a tree. And, in this young plant, arc
plainly to be feen the leaves with which it is naturally furnilhed.
The other, is of a plant which I judged, had not been cut through
tlie middle ; for which reafon it did not appear fo large as the for-
mer, nor were the leaves equally confpicuous. This is exhibited at
^g. 17, RSTABZ. The place of the future root in this plant is
niarked by R SZ, and that of the fiem by SABZ.
yVlthough I frequently repeated thefe experiments, it was only
twice tiiat I could obferve the upper part or future Hem of the plant,
in drying, feparatc itfelf from the circumjacent parts. This repara-
tion I have cauied to be exprelled ill the i'ame Jig. 17, at SABZ, and
at T Y.
I have generally obferved, that the young plant, in that part
which, in /^. -i^], is noted by EHG, occupied not more than one half
of the fpace there reprefented, and lay near the part marked H.
But, at one time, I law the young plant occupy only a third part of
the fpace ; whence it follows, that fuch fpace or cavity was nine times
as large as the plant it contained-.
Farther, I twice obferved the young plant to lie, not precifely in
the middle, but rather on one fide of the before mentioned cavity,
whence I concluded, that it had begun to vegetate while in that part,
for I law that the circumjacent parts had in that place begun to fe-
parate from each other, fo that, had the vegetation continued, the
plant would have found its way out of the fliell. This feparation of
the parts is reprefented '\njig. 17, at AW B.
Moreover, I thought it right to give fome reprcfentation of thofe
( 205 )
extended parts which farround tlie upper part of the 3'oung plant, or,
more properly fpeaking, the whole of that plant.
- Let us luppofe then, that I have cut off a fmall flice of that part
which m/g. 13 is pictured between G and H, and, that in^^-. 17, a
fmall part of the circumference of this flice, and of the fkin inclofing
it, are defcribed at V V/X. By T, and by V W X Y, tk.t iubftance
is exprefl'ed, in which the young plant, or rather the upper part of
it, is as it were, inclofed and wrapped up. The parts of this fub-
ftance, exhibit the appearance of fmall vefl'els, which lie difpofed in-
fuch ftraight lines, that they naturally feem defigned to convey nou-
rifliment to'the plant. But, in the part pi61:ured at H, ni^g. 13, and
where there will be found a kind of fwelling, thefe veffels are
flretched out to fuch a degree of finenels, that none of the parts with-
in tliem can be diflinguiflied witliout the greateft attention.
As the kernels of Almonds, Walnuts, Peaches, and Plumbs,
which are inclofed in fhells, are denominated the feeds of their re-
i'peflive trees, fo the Cocoa-nut, or fruit of the Cocoa tree, ought to
be reckoned among the feeds of trees. In the feeds, however, of the
-trees I have firft mentioned, whofe fliells are all formed with a feam
or joining, thofe fhells, when the vegetation proceeds, and the ker-
nel fwells, open at the feam, and the young plant in the kernel, hav-
ing more fpace afforded it, can expand in its growth, and ftrike its
root into the earth. But the fliell of tlie Cocoa-nut has not any feam
or joining, being of an equal ftrength and thicknefs throughout,
therefore its vegetation mull be provided for in a different man-
ner ; and this I conclude to be as follows. The moiftiire in the
Cocoa-nut being inclofed and confined on every fide, when it begins
to be agitated by that intefline motion, produced by heat, muft ne-
ceflarily expand itfelf with great violence, and, by that expanfion,
the part which contains in it the young plant, is by degrees, as the
( 206 )
])k!it incrcafcs in fize, driven out of the fhell through tlie aperture
before noted.
Tliofe, who have lived many years in India, affirm, that tliere is
no tree fo bejieficial, or which produces fo many conveniences to
mankind, as tlie Coroa ; and tiiat it is converted to upwards of
fixty different ufes by man. The nut not only fup])hes him with
food and drink, but from the 2iut is alfo extrafled a liquor not much
luilike tlic Ipirit diflilled from barley, and from the fame nut vinegar
is made. The tree itfelf furnidies mads for fmallcr vellels, and the
capjllamcnts or filaments which furround the nut are partly wove
into fail-cloth, and partly twilled into cables, which are ufed even for
large fliips. If the trunk of the tree be pierced with a fmall inci-
fion, there will flow from the wound, every day, a quart of excellent
liquor, and this operation may be performed twice in the year ; the
trees, however, which arc thus treated, are deprived of their fertility
for that year.
If we compare the fize of the Cocoa-nut, with the very fmall plant
it contains, we may i'afely lay, that the nut is above one hundred
tlioufand times larger than the plant, and we may thence conclude
that this nut, and the pleafant liquor it contains, are deftincd by na-
ture, or v>hich is the fame, by Providence, for the ufe of man, and to
i'upply many of his \\ants.
4-
On hops.
X_JF the Hops which grow in the Low Countries, thofe from Liege
are preferred to ours here in Holland, and, I doubt not, with reafon,
becaufe the territory of Liege is one degree and an half more to the
fouthward than Holland, conlequently the Hoi)s will fooner come to
maturity there ; befides, in the lands about Liege tlie foil is deeper
than ours. The following are the obfervations I have made upon
this plant.
I examined by the microfcope, thofe leaves of the Hop, which
compofe the pod, or cafe, containing the feed ; which leaves, being
remarkably thin, afforded me a very pleafant obje6l to behold, the
veins or veflels fcattering themfelves in all dire6tions about the
leaves, and, in fome places, uniting again. Some of thefe veflels, I
perceived to be tilled with a red fubftance, others were of a fpiral
figure, refembling thofe veins which I have obferved in the leaves of
tea.
Many of thefe leaves, I obferved to have a fmall feed adhering to
them, at that part, where the footftalk of the leaf had been joined.
And, indeed, I think, that thefe fmall leaves tlius bearing the feed,
ave fo formed, that each (hall produce one feed, but, it is my opinion,
that the feeds, when the leaves do not grow to perfe6t maturitv',
cann.ot ripen.
Many of the feeds I dilTeCied, and found noticing in them, except
the young plant, which was chiefly compofed of the part that would
in time become the root. Tliere were, howe\xM-, t\\'o leaves formed
Cc
( 2C8 )
ill the plant, but nothing elfc rcinarka1)le, except an innnenle number
of fniall velTcls or veins, dirperled throughout the beginning root.
All thel'e feed pods or leaves, chiefly in that part through which
they had received their growth mvd increafe, were covered with ex-
ceeding minute globules, glittering with a beautiful yellow, like gold.
As far as my eye w^as able to judge, thcle globules were in diameter
about equal to the thicknefs of an hair of one's beard, but fome of
them not fo large. I do not confider them to be the fruit of the
Hop, but, fome matter or fubflance, ifliiing from the plant, fuch, ■
for example, as if it was turgid with a fuperabundant quantity of
juices, or, that the lieat of the fun might fome days be remarkably in-
tenfe, and that by the very great quantity of juices, or their extraor-
dinary expanfion, they had burft: through the vefl'els. Many of them
I broke, and I did not think that they were covered with any fliell or
coat, farther than that their external furface being hardened in dry-
ing, exhibited fomcthing of that appearance. They contained only
a limpid oil, of a glittering yellow, and alfo other globules, much
1 mailer, but more folid, and which with the oil, filled up the cavity
of thofe firfl: mentioned globules.
This appearance of globules, on the furface of the leaves, I think
very fimilar to what I obferved fome years ago, at a houfe where I
was upon a vifit ; the back part of which houfe, v/as covered with a
vine, facing the fouthcrn fun. The young flioots of this vine, I ob-
ferved to be, in many places, covered with tranfparent globules, and
I judged them to have arifen from the fuperabundant juices, which,
by the heat of the fun, had been brought forth in fuch plenty, that
there was not a paffage for them through the narrow \efrels of the
branches, fo that they might be abforbed by the grapes. And the
warmth on this vine feemed to me, to be farther augmented from
this circum (lance, that the ground which covered the root, was very
i'uriouny paved witli fmall ditierent-coloured pebbles, without an
( 20(> )
Iierb or blade of grafs appearing between them. And the juice, tliiis
expelled from the branches/was infpiflated or thickened on their fur-
faces into globules.
Upon examining tlie globules on the Hops by the microfcope, I
found, that the part which might be called their coat or ihell, was not
fmooth, but rough, and in wrinkles, occafioned, as I concluded, by
this, that the juice which iffued from the plant, and formed itfelf into
globules, liad, in part evaporated, whereby the outer furface or fkin
of thofe globules, contracted into wrinkles.
Thefe yellow globules, when broken, and put into a clean glafs, I
fuffered to fland in tlie glafs for fome days, and theii applied myfeU"
to examine the oil. I found that great part of tli'.s oil, had collected
jtl'elf into thin oblong particles, and, in fuch numbers, that I could not
but filently wonder at the figlit. Where this oily iubllance lay mucii
difperfed, there, the oblong particles I have mentioned, did not ex-
ceed in length the diameter of a very fine thread of wool, but, where
the oil was collected in larger quantities, they were four times that
fize. In fome places, I obferved oblong particles, with twelve points,
ilTuing, as it were, from a center, with one of their ends terminating
in a point, the others, blunt or obtufe.
- Now, we may lay it down for a certain truth, tliat thofe pellucid
nnd oblong particles, which I have mentioned to be intermixed with
the oil, although, by their minutenefs, they efcape our fight, are
really a fpecies of falts, and that the bitternefs which Hops impart to
beer, is produced by thofe I'alts. And we may alfo be allured, that
thefe minute falts, althougli they may be a thoufand times lefs than
what can be feen by the microfcope, do yet, agree in lliape and
figure, with the larger falts of the fame I'pecies compounded of them,
in like manner as we obferve in common fait, in nitre, or fait petre,
and in many other falts. The fame may be obferved, in that kind of
fugar call.ed fugnr-candy ; for, upon this becoming damp, on being
Cg 3
( 210 )
expoled to a moill atinofpliere, w hen it aftenvards dried, I have heard
women complain of its having loit its bri«^ht colour. Upon examin-
ing into the realbn of this, I found, that the furface liad been in part
diU'olvcd bv the moift air, and when, in drying by the fire, it again
became hard, an incredible multitude of I'mall particles, very many
of which agreed in Ihape with the larger parts, had collefted uj)on
the furface, and this colleflion of minute particles, clouded the bright-
nefs of the fugar-candy.
But, to return to the falts in Mops ; how will tholb philofophcrs get
over the diHiculty, who obllinately contend, that bitternefs is caufed
by a fort of minute hooks in the falts, which by their pun(5lures pro-
duce that tafle we call bitternefs ?
I have often laid a fingle leaf of the Hop, fuch as I have defcribed
it. upon my tongue, and held it there the I'pace of half a minute ; for
I was defirous to try the experiment, whether fuch a fingle leaf,
which is frequently covered with the yellow globules I have defcribed,
could excite a fenle of bitternefs. And, it is not without wonder, I
declare, that fuch a fingle leaf, upon being ftrongly comprelled be-
tween the tongue and the palate, I'pread all over my tongue a very
bitter tafie, and indeed, much ftronger than I expe(^l:ed.
Not content with thefe obfervations, I placed a ])arccl of thefe oily
globule.s, fome of them pounded or bruifed, fome of them entire, in
two feparate glafTes, and, w itli all tlie attention I was able, I examined
them by the microfcope, but I did not find any particular kind of
particles in them.
I then placed the glafles in my cabinet, and, that no kind of filth
or dirt miglit become mixed with the oil, I covered them with paper.
After twenty-four hours had elapfed, I examined them very atten-
tively, and, in fome few places, I perceived fome of thofe oblong par-
ticles I have before mentioned, which were very fmall and thin, and
after twenty-four hours longer timC; a much larger portion of ftich
( 2U )
falts was difcoverable. Thefe obfervations were in the winter, when
the weather was not favourable for i'licli enquiries ; but, liad they
been made in a milder feaibn of the y<-"'ii"> I doubt not, that the falts
would have been formed more fpeedily, and in greater plent3^
I think it might be wortii while, in the fummer-tim.e, to cxamins
the flowers and bloflbrns of various trees, particularly thofe, of which
bees appear the fondeft, by which examination it might perhaps be
dilbovered, what kind of fubftance, if any, and of what qualities or
properties, ilTues froin fuch flov/ers, and adheres to their I'urfaces.
Atone time, in tlie month of Ociober, I was informed by a IIoj)
Faitor, tliat the Hops in tliat year, were of an excellent quality,
whereupon I procured fome of the feed pods, of that year's growth.
Upon exainination, I found each of thefe feed pods to contain thirty
or even forty feeds. When I had ftripped the feeds of the fmall
leaves or integuments furrounding them, I obferved, that the young
plants within them contained, in proportion to their fize, abundance
of oil.- I farther noted, what I have already mentioned, that each
young plant had two leaves, and thefe in proportion to the minute-
nefs of the plant, were remarkably long. Thefe leaves lay in each
feed compared and twined together, much like the fpiral folds in the
fliell of a fnail ; and, when I laid open the folds, I faw within them.
Hill more leaves, but excellively minute, and v\ hich indeed, I could
not difcover in all the feeds. From hence it appears, that the feeds
of the Hop differ from molt of the larger fort of feeds, and do not
contain in tliem any fiibftance to nouriih the young plant, v.-hich
p\mt therefore is more perfectly formed than that in the ku-ger feed
of the Chefnut.
As to thofe beautiful globules which I have before mentioned to
have obferved, thofe, in this fpecimcn of the Hep, were dried, and
rather fhrivelled. Having broken them, I put them into a glafs, and
breathed on them Vvith mv varm breath tv>o or three times, where-
( 212 )
upon tiio oil difi'olvecl into a wonderfully fluid fubflancc. Tlie glafs
I then placed, where no duft could reach it, and, upon examining it the
ijext da}', I law fueh a inultitude of falts of different magnitudes dif-
perled about the oil, as it would almoft exceed belief to relate. Moll"
uf thel'e I'alts were pointed at each end, but many of them were i"o
niituite. that their figure could not be known or judged of, but by re-
ference to the larger oik^s adjoining to them. In fome of my obfer-
rations on this oil, I found the falts to appear in it, at the expiration
of only half an hour after it had been put into the glafs, and they
ijicreafed in number and fize every hour, the fmallcr growing larger,
and the oily liquor evaporating ; and I found that this fpecimen of
the Hop ])lant, contained twice as many falts as were in the former
cue.
I obfer\ed one thing which feemed flrange to me, namely, that
many of thofe oblong falts which I had faid were pointed at both
vnds, did not extend in a ftraight lino, but were fomewhat bent or
doubled together ; but, whether thefe falts fo bent into a bow-like
figure, (.lo, for that reafon, excite the motion or fenfation in our
tongues, \\ hich we denominate bitter, I leave to be examined by
pthers.
On cochineal.
W HEN I lirft applied myfelf to invefligate the nature of Cochi-
neal, I concurred in the general opinion which then prevailed, that
it was the fruit of fome tree ; and, having at the requeft of the
Honourable Mr. Boyle, further profecuted the examination, cacli
fingle piece, or fruit, as I then thought it, appeared to contain one
hundred or upward.s of what fcemed to me to be v^ry fmall feeds,
fliaped like eggs, each inclofed in its particular membrane ; thefe
objects, however, I could not bring into view, until the Cochineal
had lain in water for Ibme hours, and then, the outer fkin being taken
off, thefe apparent feeds, which were very foft, prefented thcm-
felves ; many of which were inclofed in the membranes I have
mentioned, which feemed to be their natural coats or coverings, and
were twice as large as the ieeds thcmfelves : the membranes were
filled with a \\atery fubflance, of a lovely red, but the feeds were of
a dark red or tawny colour. The feeds themfelves, upon being dif-
fe6ted, appeared toconfift of nothing but very )riinute globules of a
red colour.
Tlic remainder of the Cochi;ical, or that part of it wliich inclofed
all thefe feeds, was compofed of very thin membranes, which' were alio
of a red colour, except th.at a very fmall quantity v,as to be feen, of a
certain colourlefs fubilance, which, to me, had the appearance of an oil.
And to give an idea cf tlie general appearance of the figure of Coclii-
neal, I know not any manner of exprefling it, better th.an by compa-
rifoi'i, Vvith a parcel of dried black currants, with their (kins and feeds.
( 214. )
iviiaid bciiio: iicverthclels had to the different i"ues of the currants,
and the Cochineal. Laftly, when I divided the membranes or feeds
of which Cochineal appeared to confift, into as thin portions or par-
ticles as I was able, thole thin particles, did not, as 1 may fay, exhi-
l)ii any particular colour.
The preceding obfervations I communicated by letter to Mr.
IBoyle, from wlium I received an anfwer, to the following efte6l:
that he had under flood from a C/overnor of Jamaica, that Cochineal
was produced from the fruit of tlie fig-tree, when in a flate of decay,
at which time, there proceeded from thence, certain maggots or au-
relias, which changed into flies ; that thefe flics fettling on the trees
were tliere killed by making fires under the trees, the fmoke of
which caufed tfiem to fall down ; after whicli, tliey were flripped of
tlieir heads, the fore parts of their bodies, and their wings, and the
remainder preferved for ufe, fo that Cochineal was properly, and in
trutii, the hinder part, or tail of a fly, and confequently, that my ob-
i'er\ations were fo far correcl:, that the fubltances I had feen were
really eggs, fuch as are found in the hinder part of the hlk-worm's
moth.
To this I replied, tliat, in my preceding obfervations, it was im-
pofhble for me to judge, that Cochineal was an animal fubftance,
becaufe there was notliing to be feen in it, that relembled an animal-
cule, and that I had concluded, if it had been an animal, it would
have been devoured by thofe minute animalcules, called mites ; and
I added, that in confequencc of the information communicated by tfie
Hon. Pvjr. Boyle, in his letter, I had repeated my obfervations, the
refult of which as 1 communicated them to him, is as follows.
On tliis renewed invelligation of the f "ubjedl, I was fully convinced,
that every fn^.gle grain of .Cochineal, was part of an animalcule, from
which, not only the head, the fore part of the body, and the wings,
had been broken oft", but tliat alfo the legs, and that part of tiie body
( 2iJ )
to wliidi tlie legs are joined, had been thrown away, fo that nothing
was left, except the animal's hinder part ; and I imagined, tliat
the colourleis fiibrtance I before mentioned, and which is to be ob-
ferved in the chinks or creafes in every grain, is fome preparation,
apphcd to the Cociiincal, when it is collefted for fale, to defend it
from the mites, which otherwile would deftroy or devour it.
Thcfe creafes or rings, in every grain of Cochineal, I imagine are,
the articulations or joints, in thole kinds ofmaggots or caterpillars,
which afterwards change into a flying inie61; : And I did not doubt,
that, at the proper feafon, when a fimilar kind of infers could be
found in this country, I Ihould eliablilli that fa61:, allowing only for
the ditference in fliape and colour between them, and thofe which
conftitute Cochineal.
After this, I examined a large parcel of Cochineal, and in it I
found feveral of the fliells or coverings of the wings, which fliells
were of a black colour, with crh a red Ipot in the middle. Many
infefts are provided with thefe kinds oflhields, fhells, or cales, to de-
fend their wings and the hinder parts of their bodies, which are
very foft, from injury; and, when they prepare to take their flight,
they ere6l thefe fhields or cafes uprjght, and fpread their wings.
In this parcel of Cochineal, I alfo found among the grains, fome
fragments of aurelias, which I concluded liad been formed from the
maggots or caterpillars of this fpecies, and, in one of them was a piece
of a maggot, which, in part, fcemed to have been devoured by mites.
The children in this country, are accuftomed, in the fpring time,
(when the white nettles, or, as they are commonly called, the blind
nettles, are in bloflbm) to go in fearch of a fpecies of fmall flying
infe6fs, called by them lady-birds, which, for the moft part, are to be
found on tholl^ nettles. The fubje6t now before me, caufed me to
turn my thoughts on thefe infe6ls (though they are fmaller than
thofe whofe bodies conftitute Cochineal) and I employed fome chil-
D d
( oiG )
•clren, at the proper feafon, to collecl Ibnie of tliem for nie ; judging
tlr.it, when ilripped of tlicir wings with the cafes, and their heads and
ieet, the remainder would be found to reiemble Cochineah
Thefe lady-birds, as they are called, I killed with the fmoke of
liilpluir, and afterwards dried them ; and when I had taken oft' the
red Ih.'lls or cafes which cover the hind parts of their bodies, I found
under them two red wings, the extremities of which were folded to-
gether, becaufe, being longer than the cafes, they cannot otherwife
be covered by them. I alfo took off their wings, feet, and heads,
and then I found, that the cavity which is feen on every grain of
Cocliineiil, is on the back or upper fide of the animalcule, and is
caufed by the drying ; that part of the grain which appears with a
kind of rifing, is the lov/er part or belly. As to thofe grains in Co-
chineal, wiiich have fmaller cavities than others, I conclude, that they
mull iiave been the female inl'edls, whole bodies, being filled with
eggs, do not admit of their contra61:ing in fo great a degree ; and
though the hind parts of the bodies of thofe infc6ls which compofe
Cochineal, do fomewhat difter from thofe of the lady-birds, yet, I
was now, more than ever, aflured, that, not only the inie^l which
produces the Cochineal, but alfo thofe others I have ju ft mentioned,
are formed from maggots or caterpillars. For, if we confider the
nature of all thole flying animals which are bred from caterpillars,
maggots, or, what are called gentles, we fhall find, that all thofe
annular i)arts, articulations, or circular creafes, which are in the
caterpillars, maggots, and gentles, are alfo found in the flying in-
fects bred from them ; and in the fame nund^er. To inftance in the
gentle, froin which tiie common fly is bred; if we examine the fly,
and confider its head to be comiwfed of one of the annular parts, or
articulations in the gentle, we Ihall find that tjic breaft to which are
joined the fix feet, contains three diftin^l articulations, and the hind
part of the body five moie. In a word, the body of the fly is divided
C 217 )
into nine fcveral parts, joints, or articulations, aixl fo many alfo are
found in the gentle. This gives the reafon, why wc mult r.ct iup-
pofe, that the rings or creafes which we fee on the grains of Cochi-
neal, are accidentally produced in the drying, for they were com-
pleatly formed in the maggot, from whence the flying infedt ifiiied,
the hinder part of whofe body conftitutes that fubftance named
Cochineal ; of which, if we examine the grains, we fliall find them
to contain ten articulations ; and the fore part of the infe6t's body,
which includes the head and feet, and the wings with their cafes,
being compofed of four joints or rings, it follows, that the Cochineal
infect is formed of fourteen joints, rings, or articulations.
After I had left the grains of Cochineal in water, for the fpace of
twenty-four hours or upwards, I obferved, that the cavity, which
liad been caufed in them by the drying, was fwelled and extended
to its original fliape, fo that the grains appeared exacStly to agree, iii
form and make, with tlie hinder parts of thole infedf s, wiiofe wings
and bodies are covered with Ihells or cafes.
4.
Ail. account of fame pieces of Amber prefented to the Author ; alfo of a
fnbftance refembling burnt paper, reported to have fallen out of the
clouds in Courland.
x\ PrufTian Gentleman, by profcflion aphyfician, on a certain time,
earneflly requefted me, by letter, to receive a vifit from him, and,
\\ itii the lame letter, tranfmitted to me, Ibme i'mall pieces of Amber,
which, he faid, were fent as a preient to me, from fome perfons of
note in Pruflia.
In thefe pieces of Amber were feveral fmall animals, namely, a
Fly, a Gnat, a Spider, and an Ant. In the two firft of thefe crea-
tures, I not only plainly iaw the wings, but, by the microfcope I
could difcover the featliers and hairs on them, and alfo thofe protu-
berances or appearances like coral beads, of which the eyes of thofe
inlec^ts arc compofed ; I alfo faw the hairs, azid nails or claws on all
of them, as plainly as if they had been placed before the microfcope,
without any intervening medium. In one of thefe pieces of Amber, I
law a little piece of ftraw, in which I could diftinguilh the tubes or
veflels of which ftraw is compofed.
The manner how tliefe animalcules became inclofed in the Am-
ber, and the nature and compofition of Amber, are equally unknown
to me ; and I cannot llibfcribe to the theories or opinions of others,
which do not feem fufficiently fupported, nor am I at prefent parti-
cularly called upon, to make any farther enquiry into this matter.
The fame Gentleman, among other fubjedls of converfation, told
me, that in Courland, there had been found in a field, fomething re-
fembling burnt paper, being as much as two or three flieetsinquan-
( 2i9 }
tity, which it was reported had fallen from the clouds ; that lie liad
procured a piece of it, which he had examined by the microfcope,
but could not form any fatisfaftory judgment refpe6ting it. And,
finding me dcfirous of feeing this pretended paper, he afterwards
fent me a piece of it.
I had not had this fuppofcd paper in my poirefTion half an hour,
before I obtained, by the help of the microfcope, fo much infight into
its nature, that I judged it to be a vegetable production, of a fort
which grows in the water ; and I concluded, that if the fa61 was, as
reported, that it had fallen from the upper region of the air, it
had been carried up thither by what is called a water fpout ; though
I am much more inclined to believe, that by fome heavy ftorm of
rain, or the melting of fnow, (if the country is mountainous) the
ponds or ditches might have overflowed, and carried with their curr
rent this vegetable produ6fion while green, leaving it on fome field of
grafs or arable land, and there, by the fun and wind, it might be very
much dried, fo as, in fome meafure, to refemble burnt j^aper : more-
over, I was well aflured, that I had feen this kind of fubftance in con-
fiderable quantities in ponds, ditches, or caiwls, in this country ; my
only difficulty was, to diicover, how it acquired the black or appa-
rently burnt colour before mentioned.
To fatisfy myfelf in this refpeft, I went to fome ftagnating pieces
of water in the neighbourhood of this town, where I had feen tliis
vegetable, which is an aquat-ic plant or weed, in great abundance,
fome of it I brought home v/itli me, and fpreading it open between
pieces of thick pai)er, I laid it before the fire to dry. I then perceived
that where many pieces lay heaped one on another, their natural
green was changed to a blackifh caft ; but, where the pieces lay fingly,
they preferved their green colour.
After this, I examined the before mentioned imaginary paper more
jiccurately, and I faw very difiinc^Iy, that it was exactly of the lame
( 2Q0 )
make and texture. ^^ ith the pieces of green plant or v.'eccl I liad ga-
thered ; and, upon examining this lafl:, when in the lame Hate as I
took it out of the water, 1 law bv a common magiiiher, wliat feemed
to me like very thin threads in it, much finer than hairs ; they were
round, and their membranes or coats very tranr])arent, and they were
filled with great numbers of green globules, of dilferent fizes, the
moll of them about the fixth part as large as a globule of tlie human
blood. And though this green weed, when 1 lirft laid it todr3% was
iji parcels heaped together, to the thicknefs of one's little finger,
yet, when dried, it was no thicker than common pajier, w hence may
he gathered, what a vaft quantitv of watery particles are contained in
this aquatic plant or weed.
In a word, this fuppofed paper from Courland, which is there
reported to have fallen from the clouds, and the green weed or leaf,
prepared by me in nnitation of it, are, in their component parts, fo
exactly ahke, that they may be faid to be one and the fame. For,
in divers of the filaments or threads of the firfi, I could perceive the
membranes compofing them to be the fame as in the fecond, and, in
an hundred places, I could perceive thefe filaments to be furnilhed
with joints, which were alike formed in each fpecimen.
Thefe obfervations lhew,how far conceit and imagination will lead
fome people, and who knows, how many perfons may have pieces
of this imaginary paper, treafured up in their cabinets as great
rarities ?
Of the herb Periwinkle , zvherein the opinion that it does not bear any
feed, is refuted.
jL was induced to turn my thoughts to the confideration of tlie
herb Periwinkle, from an opinion which is entertained, tliat, tliough
it bears a flower, it does not produce any feed. I therefore pro-
cured fome. bloHoms or flowers of tliis herb, as they grew on the
flalks, for I was well aflured, that no flower is produced by any
plant, which, when it falls off, is not fucceeded by fome kind of
feed. And, upon examining by the microfcope thefe flowers, and
the remains, as I may fay, of fome of them, which adhered to the
llalk, in the i)laces where the flowers had fallen off, I very plainly
faw, that thefe remains were formed for the particular purpofe of
producing feed ; for, in fome of them, I faw two or three feeds,
though very minute.
An acquaintance of mine, a refpeftable perfon, gave me fome of
thefe flowers, which he had gathered from a plant, growing in a
place, where the rays of the fun feldom penetrated : and the fame
j)erfon, paffmg by a houie, where this plant was placed as aii orna-
ment, and obfcrvhig that there were Ibme feeds on it, he brought
me a few of thofe feeds with the fliells or pods inclofmg them. Thefe
feeds were of a dark colour, oblong, and much larger than I
expected to have feen, and they were inclofed in a ftrong and
tough fliell. They were not much ihorter than coffee berries, though
the coffee berries are four times as thick ; and laftly, the feeds of
( 222 )
the Pemvinkle are dilVinj^iiiiliable bv the fame kind of creafe or
think, as is to be feeii in coffee berries.
Six of thefe feeds, I fteeped in water for feveral hours, in order
that I might be able to cut them, through the hard Ihell or hufl-;,
into very thin flices ; and, upon placing thole flices before the mi-
crofcope, I law, in evoy feed, the young plant concealed. I faw
likewife, in feveral of them, the two leaves with ^vhich thefe kijid of
voung plants arc generally provided, and thefe fmall leaves, ^^•]licIl,
m dilleciting the I'eed, I had cut through, appeared fomcwhat of a
flat ihape : I alfo could diftinguifh the veins and venels in thefe leaves.
Upon repeating the experiment, I cut through that place in the feed
which partly Ihoots upwards into a ftalk, and partly jienetrates down-
wards into a root. And here, I could difcern the vellels, deftincd to
convey tliejuices upwards or downwards, to thofe refj)e6live parts of
the plant. In Ibme of thefe feeds, however, the young plant was not
conipleatly formed.
After this, I cut the outer luifk or fliell, and the farinaceous fub-
llance which furrounded the young plant, into very I'mall piaces
Icngthwife, in order to take the young plant, whole and entire out of
the feed. And having fuccecded therein to my wilh, I clearly per-
ceived in the plant the two oblong leaves I have mentioned, with their
veil'els and veins ; and I farther faw, that the fides of the leaves,
which lay next eacli other, were fomewhat flat, the outer fides of
them rounding. The veilels on the fides of the leaves, on account
of their opacity, I could not perfec^lly diftinguifli. The young plant,
inclofed in the feed, I judged to be fixteen times fmaller than the feed
itielf
Tlie young plant in the feed of this herb. Periwinkle, is remark-
ably long and flender ; the plant itfelf does not rife up into a fialk,
but creeps along on the ground. And, as in this refpedl, it is fimilar
to moll plants of ilu vinefpccics, which are by nature what is called
( 223 )
creeping, and" therefore are ullially trained againft fome fupport ;
fo, tlie young plants, in the feeds of the Periwinkle, and in that of
the Vine, I mean, what is contained in the grape-ftone, are of a
fimilar fliape, though -the feeds themfelves, are wholly of a different
fio-Lire : and, as to the circumftance, that feeds are feldom found in
the Periwinkle, whence the notion of its being entirely deftitute of
feeds, feems to have proceeded, I guefs this to be tlie reafon, that,
it is generally planted in the nioft obfcure and unfavourable places,
where it receives very few of the fun-beams.
Moreover, J examined the mealy fubftance which furrounds the
young plant, and found it to confiit, in part, of veficlcs, of equal
fizes, but much larger, than the veficles \\hich are found in the
cocoa-nut. When I Itrongly comprefled thefe mealy particles, I ob-
ferved many oily parts, of a globular form, and fo large, that they
feemed to be com po fed of many receptacles of that oil.
Finallv, I placed fix of the Periwinkle feeds in muifl faiid, which
I put into a flrong and large glafs tube ; this i carried, for the
Ipace of an entire month, in my pocket, where, in the day-time, the
natural heat of my body was imparted to them; and, at the expi-
ration of that time, I took out one of the feeds, but, I did not per-
ceive any alteration in it. I therefore kept the remaining five leeds
in the fand, taking care, that they fliould always be moill. And,
at the end of another month, I again e. amined them, but found their
figure unaltered, though the feeds were grown fo loft, that, they
might be broken with one's nail only. I then took the 3'oung plants
out of the feeds, and I could not obferve in them any tendency to-
wards decay or diflblution, nor any advance towards vegetation or
increafe.
Ee
Of the root named * Parcira Brava.
OEEING, in the Pliilolbpliical Tranfat^tions of the Royal Society
of London, the Root named Pareira Brava, very much extolled, on
account of the medicinal virtues it is faid to poflefs, I was induced to
publifli tiie obfcrvations I had made on that root.
A gentleman of fome confequence in this country, produced to
me a piece of tliis root, adding-, tliat it was difficult to be met with,
and was very highly valued, for that a fev/ grains of the poN\der,
adminiftered to a fick perfon, would be found of fingular benefit.
In order to examine this wood by the microfcope, I obtained from
this gentleman a fmall piece, from which I cut off' about the quan-
tity of a grain, and this again, I divided into frill fmaller flices,
fome by a longitudinal, and I'ojne by a tranfverfe fe6lio!T. I thens
by the help of the microfcope, difcovercd, that the wood contained
many very large pores, in fome places dilpofed fnigly, in others, two
or three placed adjoining to each other. I next, put thefe very thin
flices into a pcrfeilly dean glafs, and j)oured water on them, in
order to feparate from them, tlie falts they might contain, which
I was very defirous to examine. Then, upon applying the micro-
fcope, I obierved great numbers of exceflively minute, glittering
particles difpofed throughout the water. Thefe particles \\ere of
various and peculiar fliapes, very like thofe falts which I have oftea
* This is the root of an American convolvulus, {ths cijfampelos Parcira oi lAnnxus)
brought to us from Brczil. The read-rr v/ill find it defcribcd in the New Edinburgh DiC—
pen(;Uorj', being an improvement of Dr. J^ewis's,
( =25 )
found in fea-filli. Then, becaufe I imagined that thefe particles, as
far as I could judge by my eye, were no other, than abfolute falts,
I immerfed fome of them in burnt wine, to fee whether they would
be difTolved in the wine. But, all of them preferved their Ihapes
unaltered, fome of them exhibiting on the glafs, a triangular figure,
-and fome being perfe6tly fquarc. But, it was my opinion, that thefe
falts, had been inclofed in certain veficles in the root, and, when
extrafted from them by the water, had concreted into the falts I
have defcribed ; for, I had obferved the Pareira Brava to be fur-
nidied with many of thofe veficles.
Not having fully fatisfied myfelf by the examination of this piece
of the Pareira Brava, I endeavoured to purchafe fome of the root in
our town, but I found, that the very name of it was unknown here ;
however, in a neighbouring town, where it had been in ulc for about
xi twelvemonth, I procured an ounce and a quarter, and, upon com-
paring this with the former fpecimen, by the help of the microfcope,
1 found them to correfpond exactly.
This laft-mentioned root, was a piece, fplit lengthwife, and, as
■near as I could judge, of five years growtli : it was half an inch in
thicknefs, and tlie texture of it appeared to me of a wonderful
make.* I divided a fmall piece of it, into very minute fragments,
and, putting tlicm into a clean glafs with fome rain water, 1 caufed
the water to boil, until more than half of it was boiled away, the
remainder I took oifthc fire, judging, that the faline particles, were,
by this boiling fully incorporated with the water. In this water,
Jiowever, I difcovered nothing by the microfcope, exCept feveral very
fmall and thin membranes fvvimming on the furfacc : I therefore
expoi'ed I'ome drops of it to the air, in order, that the evaj)oration of
the nioifture might caufc the I'alts to concrete. But, in a ii;crt tiine,
* The .luthor Ii.is not ^Jven a figr.re of this root.
E e 2
( 226 ")
there appeared lucli a membrane or film on tlie fiuTace of the waten
that nothing could be diftinguifhed in tlic fluid, except fome excel-
fively minute particles iwiniming in the water in fuch multitudes,
that, if fome of them had not collected together in the form of falts,
I could not have dii'covered them. And, I could not fufficiently ad-
mire, that from i'o fmall a fragment of the root, fucli a quantity of
falts had palled intotiie water.
After this water had flood undifturbed for fome time, and the
films on it were fubfided, I put a drop of it, about the fize
of a pin's head, into a clean glafs, and mixed with it lome blood,
which, by the jxmclure of a needle, I drew from my finger. Where-
iil)on I faw, that the globules of blood from whence its rcdnefs pro-
ceeds, were, upon being thus diluted, more feparated and fcattered than
I remember to have ever obferved. Tliere was alfo tliis remarkable
appearance, that moft of the globules had a kind of finus or cavity
in them, the fame as if one had a bladder filled with water, and by
prefling a finger on the middle of the bladder, made a cavity or fur-
row in it. And, when the globules, after afluming a flat fliape
(for when they are fomewhat difperfed or feparated, their extreme
foftnefs caufes them to become flat) got fomewhat cloler together,
they put on an oval figure, and then, the cavities I have mentioned,
alfo became fomewhat oblong. But, when globules of blood are
concreted or coagulated, they exhibit the appearance of a folid body,
the component parts of which, cannot be difiinguilhed by the eye, ex-
cept that, in the coagulated parts, they feem rather to differ in fize.
Now, having fo often experienced as I have done, how very foft
are the globules of blood, and how fpeedily, when flightly in con-
tadi and expofed to the air, they coagulate, I cannot, in any man-
ner, comprehend, how it is, that thofe globules when in the veins
and arteries, where they fo ftrongly propel and comprefs one an-
other, do not coagidate. Still lefs can 1 compreh.end, why, when
C 227 )
the fkin, or the arteries, are comprenbd with the hand, the blood
itl'clf does not become thicker.
After this, I cut the root into many ihiail pieces, botii longitu-
dinally and tranfverfely, in order to invefligate, whether thole mi-
nute falts, which I deemed to be in the root, could l)e there*difco-
vered. For, I \vas perfuaded, that there were in tlie root, Ibme
kind of veficles, full of a certain humour or moifi: fubflance, and, that
upon the evaporation of the moifture, the ialine particles which
abounded in it, concreted together, as 1 have mentioned above.
Having now plenty of the root, to purfue my experiments, I
found, that more than one-third part of it, confided of veficles,
arifing at the inner part of the root, and tending towards the exte-
rior. In thefe veficles, lay certain minute falts, collected as it were
in clufters, fo that frequently, fix or feven appeared together, in a cir-
cular pofition : and, where thefe clufters were longer than broad, I
judged that, at leaft there were tvv'enty falts in every clufter.
Thefe particles, in my opinion, when firft formed in the root, are
larger ; but, that in the drying, they become fo clofely compacted
together, that they each aiTume different fliapes, fome being trian^
gular, fome quadrangular, &c. which I have alfo obferved, in moft
things when heaped together promifcuoufly. From hence, at length
I gathered, that thefe fmall particles, were no other than very mi-
nute falts.
For my farther fatisfaclion herein, I took fome of thefe very
minute falts out of the membranes or vefic-es containing thein, and
after wetting them with rain-water, I put them into a very clean
glafs, and placed therh over a burning coal, in like manner as I
have pradifed in experiments on the globules of meal. I then ob-
ferved, that thefe particles, which, for the prefent, I will call mealy
particles, and which, before, were globular, now aflumed a fiat
ihape of a circular figure. So that, thefe particles may, perhapS;,
( 22^ )
vvitliout inipropriet}', be deemed farinaceous or mealy parts ; for,
as I have faid, their globular fonn was changed to that of flat and
circular, but of different dimcnfions. This experiment I often re-
peated, and always found the event alike.
Having never before, found thefe colle6lions of particles fur-
rounded by a membrane in any other wood, but only in certain feeds,
I v/as not content with the examination of this root, Pareira Brava,
but applied myfelf to the infpe6tion of other roots, fuch as that of
the China root*, in which, I not only found the fame kind of
fubflance. or particles, as in the Pareira Brava, but, the particles
were fo very large, that I could very plainly perceive in them, the
fame kind of chi^ik, furrow, or creafc, as I Jiave in another place
mentioned, to have obferved in the grains and meal of v.heat. And,
as to all thefe mealy particles,, in both the fubjcc^s I have mentioned,
I could perceive them, when brought to the fire, uniformly alter
their figures, from a globular, to a flat and circular (liape.
Now, fince it appears, that the particles in tlie lafl-men-
tioned root, have in them thefc chinks or creafes, and, that wlieu
wetted and afterwards dried, they change their figures as bel'ore re-
lated, we may reafonubly conclude, that the very minute particles
which abound in the Pareira Brava, have alfo tlic fame kind of
chink, or furrow, though fuch furrow is to us invifible.
Let us now fuppofe thel'e very minute i)articles, which I call
mealy ones, contained in th.e root of the Pareira Brava, to be admi-
niftere:! as a medicine, and by the heat and moiihire t)f the
body to be diffolved : let us farther fuppofe tiiat the particles, fo dif-«
lolved, are, by the contijiual motion and agitation of tiie l)ody, in or-
der, th.at they may perform tlieir office of relloring health, commi-
nuted and broken into other particles of inconceivable tenuity
« This rootis very tn'nutily dtfcribed in Dr. Aftruc's TroatTeon the Vo ercai Difsare.
( 2cr) )
and finencfs. We do indeed, hereby gain fome infight into the
manner of Nature's operation of healing ; but, in what particular
manner, tlie particles, fo attenuated, do a6i' m the accomphlhment
of her purpofe, will, if I miftake not, for ever remain undifcovcr—
able by human powers.
Fartlier, I took a portion of the root, in quantity about five grains
apotliccary's weiglit, and placed it on the fire, in order to draw from
it the oil and volatile fpirit it might contain. When tiiis Ava.s bunrt
to a coal ; in order to dilcover its fixed falts, I poured on it a little
rainwater, which watei* bt coming very turbid and foul, b}'' rea'bn
©f the burnt matter, I flraincd it through a filtering-paper, and
placed portions of it on feveral pieces of clean glafs, to the end, that
the watery parts might evarx)rate. Neverthelefs, there ftill remained
fomething of a vifcous matter, from whence I concluded, that fome
parts of the root liad efcaped the fire : this v.as all tliat occurred to
me worthy of note in this experiment.
A certain phyfician, in converfation on the fubjeci, fuggefied to
me, that if the coal of the root was burnt to a white afli, tlie falts
would certainly be difcovered. But, though, in attempting to efte6l
this, the glafs on which the pieces of root were placed, always
melted by the violence of the heat, the pieces of wocd were never
burnt to allies.
Hereupon, I placed fome pieces of the Pareira Brava root, on a
piece of charcoal, fuch as the goldfmiths ufe, and directed tive
iiame of a large candle againfl; it, by the blaft of a blow-pipe ; \ry
which means, the root was ahnoft all confumed to a wliite afli : tin?,
I caft into a fmall quantity of water in a glafs, and filtering the wa-
ter, which was very turbid, I let it fall drop by drop on different
glalles, made perfectly clean. One of thefe glades I i)laced on a
burning coal, in order to evaporate the moifture, for, at that time,
the; atmofphere was very damp, and rainy. When this drop of wa-
( '-^3° ■)
ter was evaporated, fuch a quantity of falls appeared, that I was
aftoiiinied at the figlit ; for they hiy heaped together, in like man-
ner as, in a wood, the twigs and Ihiall branches are leen Ipread on
the ground. After they had remained thus for a I'mall time, though
within an hour, they dillblved into moifture : I found the fame ef-
fect to follow breathing" on them.
Now, what fliall we fay of this mod extraordinary and intimate
union of thefe faits with the root ? For, it has been obferved, that
though the glafs melted by the vehemence of the heat applied to it,
the falts in the pieces of root, which la}' on the glafs, were not ex-
pelled ; though afterwards, when Turrounded by a ftronger heat,
they were fei)arated fro)n the wood.
When we find thefe things upon exi>eriment, we cannot but rea-
fo;i thus with ourfelves ; How w onderful is the make and texture of
this root, arid how powerfully may the fait which is thus clofely
united to it, adt as a medicine on the human body ! For my part, if
I may fpeak my opinion, it is, that the make of thefe falts is not to
be altered by the power of firo.
Again, upon confidering whether the charcoal, which I had ufed
in the preceding experiment, might not pollibly have fome fouhiefs or
extraneous matter on it, which was imparted to the root wliilft burn-
ing, I |:)laced fome pieces of the Pareira Brava on a filver plate, and,
Avhen they feemed to be quite burnt to allies, and were glowing hot,
I threw them into ibme rain water, which had been boiled in a clean
vellisl well tinned, and only ufed to boil water for the making of tea
or coffee. This water, after (training it through filteriiig paper, I
])laced in four feparate glaOes, and fuffered it to remain there all
night. The next day, the atmofphere being dry and clear, I examined
them by four feveral microfcopes, and found, that the greatcR part,
but not the whole, of the water was evaporated. The event of the
experiment was, however, the fame as in the laft, namehs that an
innumerable multitude of the falts before defcribed, were to be leen,
and that more diltindtly than before.
On the formation of the cryJlalUne humour oj the Eye, in various animals,
birds, and fjhes.
X HEcryftalline or tranfparent body or fubftaiice, (whicli is com-
monly called the cryflalline humour) of the Eye, is, inconfiftence or
liardnels, almoftthe fame as a preferved nutmeg. "When I firfl began
to make my obfervations on it, I cut off, with a Iharp razor, fome fmall
pieces or flices, and found it to confift of a fort of fcaly particles, laid
one on another, in a kind of circular form, taking their origin from
the center, and all of them then feemed to me, to be compofed of
cryflalline globules. After I had left this cryflalline fubdance, for
the fpace of three days to dry, it became fo hard, that it flew into
pieces before the edge of the knife, after the manner of rofin.
Upon again examining its nature and compofition, I perceived, not
only the fcaly formation, and intheeiculardireftion I have mentioned,
but I difcovered, that each of the fcales or coats was compofed of
parts, lying in a circular pofition, and in regular order, in rcfpe61: to
each other. In other words, the formation of the cryflalline iui-
mour, may be compared to a fmall globe, or fphere, made up of
thin pieces of paper, laid one on another : this will ferve to give an
idea of the fcales or coats above mentioned, and, fuppofmg each
paper to be compofed of particles or lines, placed fomewhat in the
jiofition of the meridian lines on a globe, extending from one pole
to the other, this may explain the nature of the conjponent parts of
thofe fcales or coats.
Alter ^thefe firfl obfervations, I cin ployed inyfelf, more narrowly
to examine, the eyes of oxen and cows; for, I thought, that I had
Ff
( 2.]^ )
not then, invclVigateil the formation of the cryftalliiic luiinour, I'o
accurately ii*^ I ought to have clone.
I, therefore, firlt fat about exaniiniiio- tlial loelhcle or thin mem-
brane, wherein tlie cryftalline humour is inclofed, and by which it
is, as it were, Separated from the- otlicr luiinours, com)x)fino- the
llibftance of the ICye. I was then, well allured, tliat I faw this
membrane to be compofed of threads or iilaments, though after-
wards, notwithrtanding the greatefl attention that 1 could beflo\Y,
T could not diflinguifh Inch filaments.
In this examination, I iometimes, but not often, obferved, tliatthe
fmall fibres compofing the filamentary fubftance of the external coat
of the cryftaUine humour, were united to the before mentioned mem-
brane ; whence I concluded, that this membrane w as ell'ential to the
cryltaUinc humour, in order to fmooth any inequahties that there
might be in tlie filaments of its external coat, and make its round
furface perfeSily even. **
I alfo confidered with myfelf, whether tliis membrane miglit
not be formed, for the jiurpofe, occafionally, by its rompreflion,
to alter the figure of the cryRalline humour; that is, to make its
rounding flia])e flatter at times, as the purpofcs of vifion might re-
quire ; and, if fo, this part of the Eye which has hitherto been called
the cryflalline humour, ought rather to be named, the cryflal-
line mufcle of the Eye : and yet, I cannot affirm with certainty,
that I have clearly feen tliis membrane to be compofed of filaments
intermixed one among another, though, I am well allured that it can-
not be formed in any other manner ; for, I have always found every
kind of thin membrane which I examined, to be of a filamentary or
fibrous make. With regard to this, now under confideration, I perceived,
when viewing it fideways, that it was compofed of a kind of flreaks
perfe6lly tranfparent, wliich I concluded to be, fome lymphatic
vefl'els, deftined for the nourilhment of the crvftalline liumour ; but
( 233 )
\vhen I followed with my eye, thcfe ftreaks, or lymphatic vefiels, to
the part where they joined the cryltalline humour, they became ib
flender, that tiiey vanifhed from my fight.
With regard to the before mentioned fcales or coats, which compofe
the cryftalline humour, I found them to be fo exceedingly thin, that,
meafuring them by my eye, I mufl fay, there were more than two
thoufand of them, lying one on another. For, when I had ftrippcd
the cryftalline humour of the membrane in wliich it was inclofed, I
found, that its axis or diameter where it was thickeft, (for it is not a
perfe61 globe, but fomewhat flattened ) was equal to two third parts
of an inch ; therefore, from the center to the circumference, is one
third of an inch ; and, as I have found by repeated experiments, that
fix hundred hairs of a man's head, are in breadth equal to an inch,
two hundred of them conftitute the third of an inch. Nov.', I have
feen, that where ten of the before mentioned fcales or coats lay
dole, one on another, they were not, altogether, equal to the diame-
ter of an hair ; therefore, if thcfe ten be mulciplied bj- two hun.dred,
it follows, as I have before mentioned, that the cryftalline humour
is, in its fubftance or thicknefs, con)pofed of more than two thoufand
fcales or coats : and laftly I faw, that each of thefe coats or fcales'
was formed of filaments or threads, placed in regular order, fide by
fide, each coat being of the thicknefs ef one fuch filament.
In order to explain to the reader, the nature of this formation of the
cryftalline humour, that is, how it is compofed of fibres or filaments,
I have, in the following figures, reprefented thofe filaments by lines
drawn in a circle, as accurately as I was able; firft premifing, that in
Plate YIU. fig. 1. A B C reprefents the ct-yftalline humour, in an ox's
eye, of its natural fize ; B, is the place in that part of the tunica
cornea, or horny coat of the eye, through which the rays of light
pals. In the following figures, the natural dimenfions are increaied,
in order that the filaments of vv'hich the fcales or coats are compofed,
may be exhibited more diftinclly.
'F f 2
( '^31 )
In Plate VIII; i^t fig. 2, i.s reprefented the i'urface of the cr3'ftal-
line humour, pidlured at Jig. i, but, wh/icii is here to be confidered,
a« if that figure did prefcat a circular fhapc to tlie eye. Jii this
figure, are many lines to reprefent the courle or direflion of the
filaments, but, it mult not be fuppofed to give a true reprefcntation
of their numbers, the circumference of the cryftalline humour of
an ox's eye, containing more than twelve tiioufand of fuch fila-
ments. For, ten of thele filaments laid fide by fide are, (as before
obferved) jiot equal to the diameter of an hair ; and the v%hole axis or
diameter of the cryflalline humour being, as before noted, equal to
four hundred hair's brcadtli, it confifts of four thoufand filaments in
diameter. And, by the common rules of arithmetic, whereby we find
the circumference of a circle, of a given diameter, it will be found, that
the circumference of the cryftalljne humour in an ox's eye, confifis of
12571-^ filaments.
Hence we may collefl, how exceffively thin thefe filaments are;
and, ^ve fhall be firuck with admiration, in viewing the %\onderful
manner they take their courfe, not, in a i-egular circle round the ball
of the cryfialline humour, as I firll thought, but, by three difterent
circuits, proceeding from the point L, which point, I will call their axis
or center. They do not, on the other fide of the fphere, approach each
other in a center like this at L, but return in a fhort or fudden turn
or bend, wjiere they are the fliortefi:, fo that, the filaments of which
each coat is compofed, have not in reality, any termination or end.
To explain this more particularly, the fliortefi: filaments MK, HN,
and OF, whicli fill the I'pace on the other fide of the fphere, conftitutc
a kind of axis or center, fimilar to this at L; lb that, the filaments
MK, having gone their extent, and filled up the fpace on the other
fide, in like manner as is here lhev>n by the lines ELI, return back,
and become the Ihortelt filaments, HN. Thefe filaments HN, paf-
fing on the other fide of the fphere, again form another axis or center,
( ' 23/5 )
aud return in the direiStion OF, and the filaments OF again, on the
other fide of the i'phere, collect •■ound a third center, and thence re-
turn in tlie dire6t;c;ii KM ; iu th;i.t, the filaments wliich on this fide
are tlie fliortefl, on the other fide are the Icngell, and thcfe which
there are the fliorteft, are here the long;eil.
In order to exliibit more clearly to the view, the nature and dif-
pofition of thole filaments, conftituting each fcale or coat of the cry-
Aalline humour, I have given a figure of them, as feen Tideways,
and which, in the plate, is exprefl'ed by lines ; but it mufl be obferv-
ed, that in thefe Hgures, the cryflalline humour is reprefented as if
it were of a fpherical form, and, in the defcription I call it a fphere,
as being more intelligible in the defcription, though, in truth, it is not
perfeftly globular, as I liave before noted.
In Plate VIII. fig. 3, RT P S W O, is defigned to repref ent one of the
coats of the crylialline huniour, allowing for the difference in fhapq
as before noted : P, and O are axes or centers, one of v.diich, P, in
fg. 2, was fliewn at L ; the lilaments coming from the point P, ( which
in Jig. 2 is L) proceed to V, where they are fliortefi: ; from whence
they return towards P, where again they ai"e longeft, and, from
P they proceed towards W, where they are again fliorteft. In
like manner, the filaments at T, take their diredtion towards O, and
from thence towards X, and from X again towards O : fo that, in
this figure (allowing it to be confidered as an hemifphere) may be
feen the one half of the courfe or circuit of the filaments. In a word,
the filaments LI, in^^. 2, are the fame as in this, are fliewn at P S i
and the filaments between L and M nifig. 2, are here feen between
P and X, and thole between L and O, in fig. 2, are here, between P
and T ; fo that the filaments which in fig. 2, are feen between FOL
IKE, and in Jg. 3, in RT PS do reprefent the felf fame filaments.
I muff here farther obferve, that ihe filaments, of which the cry-
ftalline humour, or rather fubffance, confiffs, are thickefl about R
( =3^ ■)
mid S, and, wlieiv llicy approacli nearer, at P or O, they become tliin-
ncr or fleiiJcrtr. Finally, upon an attentive examination of the cry-
ilalline humour, we Ihall be convinced, tliat its tranfparency is not to
be exceeded by any glals, although it confills of fo many thoufand
f-'laments, MJiich is moll wonderful ; and the more, if Me confidcr,
how cloleiy the filaments mult be united, that they may admit the
rays of light to pals througli tliem in (trait lines ; for otherwife, the
cryfcalline humour would not be pellucid, but would exhibit a white
appearance.
In order to explain this formation of the cryflallinc humour flill
more plainly to fome curious gentlemen, I took a fmall tennis ball,
and woimd it clofe round about, with fome very fmall twine, confining
the twine by pins Ihick in the ball, in the pofition orcourfe which
the filaments take ; I then fpread over the whole Ibme flrong glue,
'and when it was dry, 1 took out the pins, and then the twine thus
v.'ound round the ball, gave a true reprefentation of the courfe of the
■filaments as before defcribed.
I have mentioned in the beginning of this Effa}-, that the parts
which I now plainly perceive are filaments, I then thought were
com])ofed of globules, and this, in fome filaments, did then feem to
me very apparent; but, not having feen the fame appearance uni-
formly in all, I now' conclude, that the filaments being (as before
jnentioned) m.ofc cloleiy united, it might hapi^en, that in the feparat-
ing them, fome fragments or particles of one, might ftick to another
of them, and thefe I might miJlake for globules.
After this, I took the eyes of Iheep, hogs, dogs, cats, and other
animals, and examined their cryllalline humours, in the fame maimer
as I had treated the eyes of oxen ; but, neither in the fcales or coats
conllituting the cryilallme humours, nor in tlie difpofition of the
filaments, of which each coaf or fcale was compofed, did I perceive
jtiic lead difference. Moreover, I extraiflcd the cryficdline humour.
( 237 )
irom the eyes of liares and rabbits; thefe alio, I found to confift of
fcalcs or coats, inclofed one in another, and each fcale or coat com-
pofed of filaments ; but, whereas tlie filaments com.pofing the cry-
lialline humour m tlie eyes of the feveral animals I ha^•e firlt enu-
merated, do arife from three centers, and thence are difperfed three
different ways round the circumference, the filaments in thefe two
laii mentioiied animals, take only a twofold courfe or direftion. This
is fliewn uijig. 4, ABCD, which reprefents the hemifphere, or one
half of the cryftalline humour, in the eye of an hare or a rab-
bit. E, is the center near the pupil or fight of the eye ; thefe fila-
ments, compofmg the coats or fcales, palling through, or near the
central point E, take their courfe, fome tov/ards F, and others to-
wards G, fo that F and G, on the contrary fide, conftitute another
central point.
I alfo made a drawing, which is copied ^tfig. 5, o'i tiie fame ob-
je6l, as it appeared when viewed fidcways, in order more clearly to
fliew the nature of thefe lali mentioned filaments, ^^■hich, with a kind
of fibrous fubftance, compofe each fcale or coat. I will fuppofethen,
that the filaments, which in Jig. 4, are reprefented between E F, are
the fame which in Jig. 5, are pi6lurcd at the letters lO ; fo that, the
filaments proceeding from the point I, that is, in the former figure
at E, here end their courfe at N and L, where they are the Ihortefi,
and thofe at O, take their courfe through or bcfide the jxDint or cen-
ter N, where they are the longeft, and then terminate, or rather,
with a kind of flexure or bending, return as here reprefented. In a
word, thofe filaments, which, on this fide, appear neareft the center,
would, on the fartlier fide be feen remotefl from it.
In thefe experiments, I always endeavoured, to difcover the forma-
tion of that part of the Eye which anatomifts call the vitreous or
glafiy humour, and, which in great part, fiirrounds the cryfiallino
humour, becaufc I was well afllired, that this vitreous humour, was
( ^38 )
not a watery fiibftancc, but rather a kind of pellucid nuifcle ; but,
iiotwitlidanding all my endeavours, I could not form any determi-
nate or certain judgment on this head, becaufe the fubllancc of this
vitreous humour, always changed into a kind of v.atery matter.
Moreover, I examined the eyes of fifhes ; thefe are i^erfeflly
fpherical, and I found, tiiat they confilted of the fame kind of thin
coats or fcales, laid one on another, as I have defcribed the eyes of
animals to be formed ; each coat or fcale, was alfo compofed of
lilaments, but, thefe filaments have not th.at kind of bending courfe, as
in animals; and, with all my endeavours, I could not difcover in
what direction tliey were jilaced ; for, where the filaments draw
towards a point or center, they are fo exceedingly llender, and cohere
lb clofely, that they efcape the fight, and caufe fuch a confufion of
objecls, that I cannot be certain, whether they terminate in that center,
or return back again from it. Fig. 6, ABC D, reprefents the cryftal-
line humour or fubftance in the eye of a cod-filh ; and, though I
drew the lines, here made to reprefent the filaments, from the center
or point A, to the center or point C, with only a pair of compalTes,
wider apart than in the other figures, yet the filaments which
compofe thefe fcales or coats, are not in faft thicker, except in the
middle at B and D, and the nearer they approach the point A or C
the thinner they are. Fig. 7, ihews the natural fize of the cryflal-
line humour in this eye.
I alfo examined the cryftalline humour in the eyes of birds, only
to fee how the filaments compofing their coats or fcales, took their
courie ; and, at length, after many obfervations, 1 found the filaments,
in the eye of a turkey, to take the fame direction, as thole in fiihes :
but whereas the cryftalline humour in tlie eyes of fifties is perfeftly
round, that in the eyes of birds, is flattened, as at^^'-. 8, bing with its
flat fide D, next the tunica cornea or horny coat of the eye. And, up-
f^n my cutting with a flijarp knife many pieces of the fcales or coats
( 239 )
compofing it, in order to reduce tlie fize fmaller, it altered its figure
to an oblong and flat fliape, as fliewn ^t Jig. 9, where E is the fame
part which, m fg. 8, was fhewn at D , being the point where the
filaments are united, or, in other words, where they lo clofely ap-
proach, and are fo exceedingly flender, as to become invrllble : hence
we may conclude, that the filaments which lie neareft to the central
point, being very thin, do thereby produce the oblong round Ihape,
and, where the crylialline humour is larger, the filaments in the
middle are tliicker, and thus caufe the Ihape to be flattened, which I
myfelf have feen ; for the filaments in the eye of a turkey, where
they were thickeft, were, fingly, larger than thofe in the eye of an
ox, hog, or Iheep.
I have often, while looking in a mirror, taken notice of that liquid
fubftance or moifture, with which the exterior membrane or coat of
the eye is covered, and, in which liquid, there are always fome few
very minute globules intermixed ; which moifture, aiid tlie globules
in it, as often as we fliut our eye-lids are tliereby made to change
their places: feeing this, I gathered the reafon, why it is necefiiiry
for terreftrial animals to be furniflied with eye-lids (for fiflies, and
other inhabitants of the waters do not need them) and, tliat if it were
not for the eye-lids, we fliould become blind ; becaufe if the eye-lids did
not continually, when we clofe them, moiften the external membi-ane
or coat of the e3'e, its furface would grow dry, and contra61; in
wrinkles, efpecially in ftrong funfliine, or when we approach a large
fire. And I think it very probable, that there is continually, fome
kind of humour or moifture, protruded from the inner part of the
eye through the tunica cornea, which, by the eye-lids, is fpread
over the eye : for, in feveral eyes of hogs, whofe bodies had been
immerfed in hot water, to facilitate the fcraping off the hair, I almoft
always law a tliia membrane, lying on the outer furface of the tunica
( -4° )
coniea, which was foniewhat I'calded by the water, and therefore
might eafily be taken off; and, upon comprelling the ball of the
eye between my hngers, I iaw in many places, a thin watery matter,
ilTue from the tunica cornea, and appearing on its furface, like vapour
or fleam, adhering to a glai's, and, when the preflure was continued, the
watery particles, which ftood on the furface, in the form of minute
drops, were fo much enlarged, as to run into one another. And we
need not wonder at this appearance, when we confider, that the tu-
nica cornea is compoled of nothing but particles, like llrcaks or fibrous
parts with their ramifications, and all of them very thin and flender,
I at one time cut the tunica cornea of an ox's eye into fuch
thin flices, that the thicknefs of it was feven times divided, and, in
each of thofe feven parts, I faw with great admiration (and more
diflin6lly than I had before done) the great multitudes of pellucid
ftreaks or fibres intermixed together, many of which I judged were
a kind of blood velT'els, though fo fmall and flender, that they would
not admit the globules of blood, which caufe its red colour, to pafs
through them ; and I conclude that, when we rub our eyes, thofe
veflisls may, by the; preflure, be fo extended, as to admit the red glo-
bules of blood, which, for a time, flagnating there, caufe the eyes to
appear red, or, what is commonly called blood-fliot.
But, to return to the eye-lids, it is my opinion, that they never
can be confidered as in a {fate of refl, except when they are fliut;
and hence it is, that we cannot keep them fteadily open, for any
length of time, without applying fome external force : and, as it were,
to give them refl, we frequently (and involuntarily) clofe them;
which involuntary motion in the eye-lids, does, I doubt not, by pref-
fnig on the orifice of ibme minute lymphatic veflels, caufe them
continually to emit fmall portions of the lymph, whereby the tunica
cornea is continually kept moift, as has been before obferved. And
1 have feen perfons, in a public audience, when very attentive, clofe
their eyes, though fome did this more frequently than others.
( 241 )
Myfelf, and thofe of my family, have often, when contemplating
objects by the microfcope, feen an appearance of fmall globules be-
fore tlie fight, * which, I have no doubt, were particles iihaing from
the veflels in the eye, and lying on its furface : thefe, v/ith the
leaf! motion of the eye, feemed to be in great agitation, and many
would affirm, that they faw living creatures before their fight ; but
wlioever gives this lubjeft an attentive confideration, will find, that
thele globules or ftreaks, though they feem, while the eye is
kept Hill, to be in motion, fometimes upwards and fometimes down-
wards, yet they do not alter their pofition in refpeft of each other ;
and perliaps at another time we fhall fee none, or if any, of a very
different kind. I believe, however, that this appearance is what has
led fome people to fancy, that they beheld animalcules moving in
water, even after it has been boiled, and to affirm, that thefe are the
fame kind of animalcules which I profefs to have plainly feen :
but we inuft forgive fuch perfons their error, confidering they
know no better.
* The Tranflator can give a flrong fimilar inftance, from his own painful experience ; for,
having met with an accident by which the furface of his eye was injured, the confequence was,
for fome hours after the hurt, an appearance of minute, wonderfully bright globules, feeming
to whirl round the ball of the eye with a rapidity like lightning ; and, for feveral following
days, many dark fpecks, in motion before the fight ; but all, as Mr. Leeuwenhoek fays, pre-
ferving the fame diftance in refpedt of each other : one of thefe in particular, appeared in fize,
colour, and £hape, much like a common fly, which feemed to be running along the wainfcot of
the room, or upon the table.
Gga
ADDITION, BY THE TRANSLATOR.
THE preceding Eflay is one of tlie moft curious, and the Tranf-
lator conceives, that his Readers will deem it the molt interelling, of
any in this Work ; forafmuch as it rel"pe6ls the choicefl corjxireal
gift of God to his creatures, the Blelling of Siglit : and, for the
information of thofe, who are not acquainted with the particular ftruc-
ture of that wonderful Organ, the Eye ; the follow ingdefcription of
it is fubjoined, taken from Mr. Adams's Eflay on Vifion, a i'mall
Treatifc, well wortliy the perufal of every one.
"Of the Globe of the Eye.
" If the confliai(R:ion of the Univerfe were notfo evident a proof of
" the exiftence of a fupremely wife and benevolent Creator, as tO'
** render particular arguments unneceflary, the ftru6lure of the eye
" might be offered as one, by no means the leaft ; this inftance,
" among numberlefs others, demonftrating, that the bcft ])erform-
" ances of art are infinitely lliort of thofe w^hich are continually pro-
" duced by the Divine Mechanic.
" The globe of the eye, or the organ of fight, may be defined in
" general as a kind of cafe, confifting of feveral coats, containing
" three pellucid humours, which are fo adjufted, that the rays pro-
" ceeding from luminous objc6ls, and admitted at a hole in the fore
" part of the eye, are brought to a focus upon the back part of it,
" where they fall upon a loft pulpy fubllance, from whence the mind
" receives it's intelligence of vifible objefts.
" It is not to be expected, that any account given of the eye can be
" altogether accurate ; for as it is impoflible to examine all the
" parts of the eye whilft in a natural and living ftate, fo it is alfo-
" nearly impoflible, when it is taken out of its focket, to preferve
( 243 )
" the figure of the parts entire ; a circumftance which accounts for
" the difagreement we find among anatomifis.
" Of the Coats of the Eye.
" The eye is compofed externally of three coats, or teguments,
" one covering the other, and forming a ball perfe<511y globular, ex-
" cept at the fore part, whicli is a little more protuberant than the
" reft ; within this ball are three different fubftances called humours.
" The firft, or outer coat, is called the fclerotica ; the fecond, or
" middle one, is called the choroides ; the interior one is named the
" retina.
" Sclerotica. Cor?iea.
" The exterior membrane, which inclofes and covers the whole eye,
" is called the fclerotica and cornea ; it is, however, ftrictly fpeak-
" ing, but one and the fame membrane, with different names appro-
" priated to different parts : the hinder and opake part being more
" generally denominated the fclerotica, the fore and tranfparent part
" the cornea.
♦' The fclerotica is hard, elaftic, of a white colour, refembling a kind
" of parchment ; the hinder part is very thick and opake, but
" it grows gradually thinner as it advances towards the part where
" the white of the eye terminates. The fore part is thinner, and
" tranfparent ; it is alfo more protuberant and convex than the reft
" of the eye, appearing like a fegment af a fmall fphere applied to
" a larger, and is called cornea, from its tranfparency. The cornea
" is thick, ftrong, and- infenfible ; its tranfparency is neceffary for
" the free admiilion of the light. This membrane is compofed of fe-
" veral plates, laid one over the other, repleniflie .1 with a clear
"water, and pellucid veffels; thefe plates are moi-e evidently dif-
" tin6l in the fore than the hinder part. The fclerotica is embraced;
( 244 )
" on its oiitfide by fix mufcles, by \vhich tlie eye may be moved in
" any dirc(^Uon.
" Choroides. Uvea. Iris.
" Under the fclerotica is a membrane, known by the name of the
" choroides ; it is a foft and tender coat, com poled of innumerable vef-
•' fcls ; it is concentric to tlic fclerotica, and adheres clofely to it by a
" cellular fubftaiice, and many velTels. This membrane is outwardly
" of a brown colour, but inwardly of a more rufl'et brown, almoll
" black. Like the fclerotica, it is diftinguiflied by two different names,
" the fore part being called the uvea, while the hinder part retains
" the name of the choroides.
" The fore part commences at the place where the cornea begins ;
" it here attaches itfclf more ftrongly to the fclerotica by a cellular
" fubftance forming a kind of white narrow circular rim : the cho-
" roides Separates at tliis place from the fclerotica, changes its
" direftion, turning, or rather folding, directly inwards, towards the
" axis of the eye, cutting the eye as it were tranfverfely : in themid-
"■ die of this part is a round hole, called the pupil, or fight of the eye :
" the pupil is not exa611y in the middle of the iris, that is to fay, the
" centers of the pupil and iris do not coincide, the former being a lit-
" tie nearer the nofe than the latter.
" This part, when it has changed its direflion, is no longer called
" the choroides ; but the anterior i'urface, which is of different co-
" lours, in different fubje^ts, is called the iris ; the pofterior furface
" is called the uvea, from the black colour with which it is painted.
" The iris has a i'mooth velvet-like appearance, and feems to confifl: of
" fmall filaments regularly difpofed, and directed towards the center
" of the pupil.
" The eye is denominated blue, black, &c. according to the colour
" of the iris. The more general colours are the hazel and the blue,
( 245 )
" and very often both tliefe colours are found in the fame eye. It has
" been obferved, that in general, thofe, whofe hair and complexion
" are light coloured, have the iris blue or grey ; and on the contrary,
" thole whofe hair and complexion are dark, have the iris of a deep
" brown: whether this occafions any difference in tlie fenfe of vifion,
" is not difcoverable. Thofe eyes which are called black, when jiar-
" rowly infpe6led, are only of a dark hazel colour, appearing black,
*' becaufe they are contraftcd with the white of the eye. The black
" and the blue are the molt beautiful colours, and give mod fire and
" vivacity of expreflion to the eye. In black eyes there is more
" force and impetuofity ; but tlie blue excel in fweetnefs and delicacy.
" The pupil of the eye has no determinate fize, being greater or
" fmaller, according to the quantity of light that falls upon the eye.
" Wiien the light is ftrong, or the vifual objedl too luminous, we con-
" tra6l the pupil, in order to intercept a part of the light, which
'• would otherwife hurt or dazzle our eyes ; but when the light is weak,
" we enlarge the pupil, that a greater quantity may enter the eye,
" and thus make a ftrongcr impreflion upon it. This aperture dilates
*' alfo for viewing diftant obje6ts, and becomes narrower for fuch as
" are near. The contraction of the pupil is a ftate of violence,
" effected by an exertion of the will : the dilatation is a remiffion of
" power, or rather an intermiffion of volition. The latitude of con-
" tra6lion and dilatation of the pupil is very confiderable ; and it is
" very admirable, that while the pupil changes its magnitude, it pre-
" ferves its figure.
" Anatomills are not agreed, whether the iris be compofed of two
" fets of fibres, the orbicular and radial, or of either. Haller fays,
" he could never difcover the orbicular fibres, even with a microfcope ;
" the radial i'eem vifible to the naked eye, and are fufficicnt to an-
" fwer all the purpofes required in the motion of the iris : when the
" pupil is contracted the radial fibres are Ilrait, when it is dilated,
" they are drawn mto Terpentine folds.
( 24,6 )
" In cliildrcn this aperture is more dilated than in 2;rown perfons ;
*' in elderly people it is flill fznaller than in adults, and has but little
*' motion ; hence it is, that thofc who begin to want fpectacles, are
" obliged to hold the candle between tlie eye and the paper they
** read, that the ftrong light of the candle may force their rigid
" pupils into fuch a flate of contraftion, as will enable them to fee
*' di(tin(51:ly. Thofe who are fliort-fighted, have the pupils of their
*' eyes, in general, very large ; whereas in thofe whole eyes are
*' perfe6l, or long-fighted, they are much fmaller.
" The whole of the choroidcs is opake, by which means no light
*' is allowed to enter into the eye, but what jjall'es through the pupil.
" To render this opacity more perfect, and the chamber of the eye
" flill darker, the pofterior furface of this membrane is covered all
" over with a black mucus, called the pigmentum nigrum. This pig-
*' ment is thinned upon the concave fide of the choroides, near the
'' retina, and on the fore fide of the iris; but is thickeft on the ex-
" terior fide of the choroides, and the inner fide of the uvea.
" The circular edge of the choroides, at that part where it folds in-
" wards to form the uvea, feems to be of a different fubfiance from
" tlie reft of the membrane, being much harder, more denfe, and
*' of a white colour ; it has been called by fome writers the ciliary
" circle, becaufe the ligamentum ciliare (of which we (hall foon
" Ipeak) arifcs from it.
" Retina.
" The third and lafi membrane of the eye is called the retina, be-
" caufe it is fpread like a net over the bottom of the eye ; others de-
" rive the name from the refemblance of the net which the gladia-
" tors called retiarii, employed to entangle their antagonifts. It is
*' the thinneft jmd Icafi; folid of the three coats, a fine cxpanfion of
( 2J,7 )
" the mecUr.Iary part of the optic nerve. Th^e convex lide of it
'* hnes the choroicles, the concave fide covers the furface of the vi-
" treous humour, terminating where the choroides folds invy'ard:5.
" It is an eflential organ of vifion ; on it the images of objeds are
•' reprefented, and their picture formed. This membrane appears to
" be black in infants, not fo bhick at the age of tvventy, of a gre3'iih
" colour about the thirtieth year, and in very old age almoft white.
" The retina, however, is always tnmfparent and colourlefs : any ap-
" parent changes therefore, of its colour, mv.il depend upon altera-
" tionsof the pigmentum which is feen through it.
"Optic Nerve.
" Behind all the coats is fituated the optic nerve, which paffes out of
" the fcuil, through a fmall hole in the bottom of the orbit which
" contains the eye. It enters the orbit a little infle6ied, of a figure
" fomewhat round, but compreffed,- and is inierted into the globe
" of the eye, not in the middle, but a little higher, snd nearer to
" the nofe ; an artery runs through the optic nerve, goes ftrait
" through the vitreous humour, and fpreads itfelf on the membrane
" that covers the back fide of the cryflalline.
" Monf. Mariotte has demonfi:rated, that our eyes are infenfible
*' at the place where the optic nerve enter.s : if, therefore, this nerve
" had been fituated in the axis of the eye itfelf, then the mid-
" die part of every obje6l Viould have been iuvifible, and where all
" things contribute to make us fee bed, we fliould not have feen at
" all ; but it is wifely placed by the divine artiil for this and
" other advantageous piirpofes, not in the middle, but, as we have
" already oblerved, a little higher and nearer to the r.ofe.
" Of the Humours of the Eye.
*'The coats of the eye, which inveft and fupport each other, after
Hh
( 2^8 )
" the manner of an onion, or other bulbous root, include its humours,
" by which name are uiiclerftood three lubltances, tlie one a folid. the
'• other a foi't body, and the third truly a liquor. Thefe fubftances
" are of fuch forms and tranlparcncy, as not only to tranfmit rea-
" diJy the rays of light, biit alfo to give them the polition bell
" adapted for the purpofes of viiion. They are clear like water, and
" do not tinge the objeit with any particular colour.
" Aqueous Hutnour.
" T\\Q moft fluid of the three humours is called the aqueous one ;
" filling the great interface between the cornea and the pupil, and
*' alfo the fmall fpace extending from the uvea to the cryilalline lens ;
" it is thin and cle;a- like water, though fomewhat more fpiritous and
" vifcuous ; its quantity is fo confiderable, that it fwells out the fore
" part of the eye into a protuberance very favourable to vifion. The
" uvea fwims in this fluid. It covers the fore part of the cryftalline;
" that part of this humour which lies before the uvea, communicates
" with that which is behind, by the hole which forms the pupil of
" the eye. It is included in a membrane, fo tender, that it cannot
'• be made vifible, nor preferved, without tiic moft concentrated lixi-
" vial fluid.
" It has n.ot been clearly afcertained whence this humour is derived ;
*' but its fource muft be plentiful : for if the coat containing it be fo
" wounded, that all the humour runs out, and the eye be kept clofed
" for a feafon, the wound will heal, and the fluid be recruited.
'* The colour and confiflence of this humour alters with age ; it
" becomes thicker, cloudy, and lefs tranfparent, as we advance in
" years, which isoncrcafon, among others, why many elderly peo-
" pie do not reap all that benefit from fpedacles which they migh
♦' .naturally expert
( 249 )
" Cryjlallme.
'•"The fccond humour of the eye is the cryflalline, \\hich is as
** tranfparent as the pared cryftal ; and though lefs in quantity than
*' the aqueous humour, j'et it is of equal weight, being of a more
" denfe and fohd nature ; in confiftency it is fomewhat hke a hard
*' js^^y» growing fofter from the middle outwards. Its form is that
" of a double convex lens, of unequal convexities, the moft convex
" part being received into an equal concavity in the vitreous humour,
" The cryftalline is contained in a kind of cafe, or capfule, the
" fore part of which is very thick and elaftic, the hinder part is thin-
" ner and fofter. This capfule is fufpended in its place by a muf-
" cle called ligamentum ciliare, which, together with the cryftalline,
" divides the globe of the eye into two unequal portions ; the firfl
" and fmaller one contains the aqueous humour, the hinder and
" larger part the vitreous humour. The cryftalline has no vifible
" communication with its capfule, for as foon as this is opened the
•' humour within flips clean out.
" The cryftalline is placed fo, that its axis correfponds with that of
" the pupil, and confequently it is not exaftly in a vertical plane di-
" viding the eye into tv/o equal parts ; but fomewhat nearer thenofe.
" It is formed of concentric plates or fcales, fuccecding each other, and
" thefe fcales are formed of fibres elegantly figured, and wound up
" in a ftupendous manner ; thefe are connefted by cellular fibres,
" fo as to form a tender cellular texture. Between thefe fcales is a
" pellucid liquor, which in old age becomes of a yellow colour. The
" innermoft fcales lie clofer together, and form at laft a fort of nu-
" cleus, harder than the reft of the lens. The cryftalline has no vi-
" fible communication with its capfule, fo that when this is opened,
" it readily flips out : fome fay, that a fmall quantity of water is
" eflfufed round it. Leeuwenhoek has computed that there are
"* two thoufand laminic, or fcales, in one cryftalline, and that each
Hh 2
( 250 )
" of thcfe is made up of a fingle fibre, or fine thread, running this
" way and that, in Icvcral courfcs, and meeting in as many centers,
" and yet not interfering with, or eroding, each other.
'• The yellow colour wherewith the cryltallinc is more and Jiiore
" tinged as we advance in years, mufl make all objefts appear more
" and more tinged with that colour : nor does our being infenfible of
*' any change in the colour of objecHs, prove to us that their colour
" continues the fame ; for in order that we fhould be fenfible of this
" change, the tincture murt not only be confiderablc, but it muft hap-
" pen on a fudden. In the cataract it is opake ; the feat of this dii-
" order is in the cryftalline lens.
*' Vitreous Humour.
" The vitreous is the third humour of the eye; it receives its name
" from its appearance, ^^hic]l is like that of melted glafs. It is nei-
" ther fo hard as the cryfiaUine, nor fo liquid as the aqueous humour;
" it fills the greateft part of the eye, extending from the infertion of
" the optic nerve to the cryfiallinc humour. It fupports the retina,
" and keeps it at a proper diilance for receiving and forming dlf-
" tin(5l images of objects.
" The vitreous humour is contained in a very thin pellucid membrane,
"and concave at its fore part, to receive the cryfialline; at this
" place its membrane divides into t^^ o, the one covering the cavity
" in which the cryRalline lies, the other pafTuig above, and covering
" the fore part of the cryfialline, thus forming a kind of flieath for
" the cryftalline. The fabric of the vitreous humour is cellular,
" the fubfiance oi" it being divided by a very fine tranl'parcnt mem-
" brane into cellules, or little membraneous coinpartmcnts, con-
" taining a very tranfparent liquor.
" Ligamcntum Ciliare.
.»' There is flill one j-»art to be dcfcribed, w^iiich, though very
( 2.:i )
" delicate and fmall, is of great importance ; it is called the liga-
" mentum ciliare, becaufeit is compofed of fmall filaments, or fibres,
" not unlike the cilia, or eyelafhes ; thefe fibres arife from the
" infide of the choroides, all round the circular edge, where it joins
" the uvea ; from whence they run upon the fore part of the vitreous
" humour, at that place where it divides to cover the cryftalline ;
" thofe fibres are at fome diftance from one another, but the inter-
'•' ftices are filled up with a dark-coloured mucus, giving ittlie ap-
" pearance of a black membrane.
" Of the Figure reprefenling tie Eye.
" Figijrc ID, reprel'ents a fe6tion of the ej'e through the middle,
*' by an horizontal plane pafiing through boih eyes ; the diameter of
" tlie figure is about twice the diameter of the human eye.
" The outermoil coat, which is caWed/clerotica, is reprefented by
' the ipace between the two exterior circles B F B ; the more glo-
" bular part, adjoining to the fclerotica attlie points BB reprefented
" by the fpace between the two circles at B A B, is the cornea.
" The next coat under the fclerotica is a membrane of lefs firm-
" nefs, reprefented by the tv/o innermofl: circles of B F B, and called
" the choroides.
" Adjoining to the clioroides, at B B, is a flat membrane, called
" the uvea: a a is the pupil, being a fmall hole in the uvea, a little
'• nearer tlie nofe than the middle.
" V the optic nerve ; the fibres of this ner\'e, after their entrance
" into the eye, fpread theirifelves over the choroides, forming a thin
«•' membrane, called thS retina, and is reprefented in the figure by
" the thick Ihade contiguous to the circle B F B.
'•' E E is the cryjlalline humour ; it is I'ufpended by a jnufcle B b bB,
^' called the ligamentiun ciliare. This mulcle arifes behind tlie uvc^
*\at BB, where the fclerotica and comca join togetlier at bb, it
( ^5-- )
" enters the capfula, and thence fpreads over a great part of its
*' anterior fiirface.
*' The aqueous humour occupies the fpace B A Bb Cb.
" The larger fpace Bb Db BF contains the vitreous humour,
" The foregoing dcfcription. v.-c prefume, will be found fufficient
" to give the reader a geiicral idea of the conftruftion of this won-
" derful organ : for a fuller account we muil refer him to the writers
" on anatomy. Enough has been exhibited to fliew with what art
" and wifdom the eye has been conftrudled."
The following is a quotation by Mr. Adams, from Reid's Inquiry
into the Human Mind :
" If we fliould fuppofe an order of beings endued with every hu-
" man faculty but that of fight, how incredible would it appear to
" fuch beings, accuftomed only to the flow information of touch, that
" by the addition of an organ, confifling of a ball and ibcket of an
" inch diameter, they might be enabled, in an inftant of time, without
" changing their place, to perceive the difpofition of a whole army,
" the order of a battle, the figure of a magnificent palace, or all
" the variety of a beautiful landfcape ? If a man were, by feeling, to
" find out the figure of the Peak of Teneriffe, or even of St. Peter's
" church at Rome, it would be the work of a life-time.
" It would appear (till more incredible to luch beings as we have
" fuppoled, if they were informed of the difcoveries which may be
" made by this little organ, in things far beyond the reach of any
" other fenfe. That, by means of it, we can find our way on the
" pathlefs ocean, traverfe the globe of the earth, determine its fize
" and figure, meafure the planetary orbs, and make dil'coveries in
'• the fphere of the fixed fiars.
" Would it not appear ftill more aftoniihing to thefe beings, if
" they fliould be further informed, that by means of this orgaji we
'* can perceive the tempers and difpofitions, the aft'e61ions and paf-
( ^53 )
" fions, of our fellow-creatures, even when they want moft to
*' conceal them ? tliat by this organ we can often perceive what is
" flrait and crooked, in the mind as well as the body : that it par-
" ticipates of every mental emotion, the foftell and moft tender, as
" well as the mofl violent and tumultuous : that it exhibits thel'e
" emotions with force, and infufes into the ibul of the fpeftator the
" fire and the agitation of that mind in which they originate ? To
^' many myllerious things mull a blind man give credit, if he will
" believe the relations of thole that fee ! his faith muft exceed that
" which the poor fceptic derides as impoflible, or condemns as
" abfurd.
*' It is not, therefore, without reafon, that the faculty of feeing is
" looked upon as more noble than the other fenfes, as having fome-
" thing in it fuperior to fenlation, as the fenfe of tlie underllanding,
■" the language of intelligence. The evidence of reafon is called
''feeing, not feeling, fmelling, tailing, ; nay, we exprefs the man-
" ner of the divine knowledge by feeing, as that kmd of knowledge
" which is moll perfc<5l in ourfelvcs."
It is too true, that we do not, in general, know the real value of
any blelhng, until we are deprived of it ; therefore, let us hear,
how the lofs of fight is pathetically defcribed by Milton, from his
own feeling : In his addrefs to the Light he fays,
" I feel thy fovran vital lamp ; but thou
" Revifit'ft not thefe eyes, that roll in vain
" To find thy piercing ray, and find no dawn ;
" So thick a *drop ferene hath quench'd their orbs
" Or dim fuft'ufion veil'd.
* This is a literal tranflation of the Latin words gutta ferena, a difeaf?, by which the pa-
tient is deprived of fight, though to a fpeftator, the eye does not appear to be injured ; bccaufc
the feat of the diforder is in the optic nerve, and not \a the bail of the eye. This was Milton's
xrafe.
( 2J4. )
-" Thuswiih the year
" Scafons return, but not to me returns
*' Day, or tlie fvveet approach of ev'n or morn,
" Or fight of vernal bloom, or fummer's rofe,
" Or flocks, or liercls, or human face divine ;
" But cloud inltead, and cver-during dark
" Surrounds me, from the clieerful ways of men
" Cut off, and for the book of knowledge fair
w Pi-efented with a univerfal blank
" Of Nature's works to me expung'd and ras'd,
" And wifdom at one entrance quite fhut out.
The Tranflator concludes this fubjedl in the words of the fame
great Poet, as conveying a fentiment, which a wife man muft deem
the mofl effcdiual, if not the only real confolation under fuch an
affli61:ion.
" So much the rather thou, celeftial Light,
" Shine inward, and the mind through all her powers
" Irradiate, there plant eyes, all mift from thence
" Purge and difperfe, that I may fee and tell
" Of things invifible to mortal fight."
Milton's Paradifc Loft, Book III.
i^ Mtisa^m
On the internal JormaLion uj an Ox's Tongue ; and on that of tie Hearty
in Animals, Fowls, and FiJJj,
CERTAIN profellional crentleman of my acquaintance, was
urgent with me to examine the formation of a cat's tongue, but
tliis I deferred from time to time, wiihing rather, to inveftigate the
nature of the human tongue, which I thought would be much more
worthy of examination ; by reafon, that it mufl neceflarily be pro-
vided with more mufcles than the tongues of animals : for, this
will appear manifeft, if we. confider how many various motions our
tongues murt exert in fpeaking, finging, or whiflling.
Not finding an o])portunity to procure an human tongue, or that
of a cat, I began by examining the tongues of o en, cutthig from
them fmall pieces, both longitudinally and tranfverfely : and, though
I thought that a complete defcription of the whole tongue would
take up too inuch time and labour, I determined to give a drawing
of the fmall mul'cles, and point out how they are difpofed longitu-
dinally and tranfverl'ely ; for, in an ox's tongue, the number of them
is incredible, and in this defcription will be leen, not only the won-
derful formation and multitude of thefe minute mufcles, but alfo,
we fliall be fully fatisfied witli regard to the manner in which the
tongue is fometimes extended a«d fometimes contracted, both in
breadth and thicknefs.
In Plate VIII. fig. 1 1, A B C DE F G 1 1 1 K L M, reprefents a fmall
piece of an ox's tongue, cut oft' from the fide, in that part where the
li
( "-oO )
•tongue was thickefr. In this i'niall piece are to be feen various mi-
nute mufclcs, cut tranfverlcly, which are reprefcntcd between
BCKL, and DEHI; and among thefe, again, there appear
many exceedingly minute particles, alfo cut traniVerlely, whicii,
"by reafon of their fmalhiefs, could by no means be reprefented in
the drawing, but each of them may, in fa6t, be confuiered as a
mufcle, for if, by the microfcope, we were to difleft the before men-
tioned minute mufcles, we fliould find them compofed of fmaller parts,
like a large mufcle, when diire<5ted and vie\\ed by the naked eye.
Thel'e flelhy mufcles, thus cut tranfverfcly, conflitute the i'ub-
ftance or thicknefs of the tongue ; and the mufcles pictured at tiie
three places in this figure, ABL M, C D I K, and EFG H, which
are fliewn lengthwiie, extend along the tongue from end to end.
And, as between the letters B.C K L and DEHI, is fliewn how the
flefliv mufcles appear, when cut tranfverfely, fo at ABLM, CDIK
and E FGH may be feen their figure when cut longitudinally.
All thefe flelhy mufcles, taken together, are not larger, when
viewed by the naked eye, than the fmall piece or particle fliewn at
I alfo judged it right, to take off" one of thefe flefliy mufcles, length-
wife, and to caufe a drawing to be made of it, to exhibit to the eye
its true formation, and alfo, as nearly as pofllble, to fliew thereby,
how, in the motion of the tongue, thefe mufcles are exerted, and
liow^ they change their figure.
Fig. 2, NOPO, reprefents this flefliy mufcle, which I took off
length wife, preferving the whole of its thicknefs, io that none of its
conltituent parts were broken off", except at the extremities N O and
PQ : in which mufcle feveral bendings are to be feen.
Now, fuppolmg this mufcle, placed lengthwife in the tongue, to
be contradted in bendings, we muff conclude, that the tongue then
becomes flioiter and tliicker, and the mufcles which lie acrofs it, arc
1
C 25/ )
then perfeftly ftraight ; and, that when the animal extends its
tongue, this flcfliy mufcle, /^. 13, NOPQ, and all the others which
lie lengthwiie in the tongue, are extended and become flraight, and
tliofe mufcles which lie acrofs the tongue are then inflected or bent
i!i like manner as reprefented in the former mufcle at^^. 13, NOPQ.
When this mufcle had Hood three months before the microfcope,
it became covered with a fort of mouldinefs,* which, bearing a re-
femblance to fmall flowers, I dire6ted the limner to imitate ' tliem
as nearly as poUible in his drawing, and they are to be feen at
RRRRRRR.
The fiefiiy mufcles, whicli m fg. 11, appear cut tranfverfely,
are, in the part lying between BC K L, four diltindl: and feparate muf-
cles, and, in the fpace between DEHI, fix of the fame kind, all of
tliem diftin^l from each other. The parts, or fpaces between them
in the figure, are no other than membranes, and particles of fat,
lying within thofe membranes. For, I never faw in fuch a mufcle as
is exhibited in fig. 13, NO P O, any vein, nor any detached particle
of fat, but every one of thefe kind of mufcles, as far as I have hither-
to obierved, is always enveloped in a membrane, and, if the ox is
a very fat one, particles of fat will be leen in the membrane.
It fliould be remembered, that every one of thefe mufcles'
mull have its tendon, or terminate in a membrane which conftitutes.
a tendon, and not only fo, but every oblong flefliy particle, of which
each fuch mufcle confi Its, and which appear infig. i3,NOPO, mull
alfo be provided with a tendon, or terminate in a membrane as he-
fore mentioned, and all thefe tendons and membranes ( in ray judg-
ment) do, together, conftitute that part which many take only for
an inner fkin, wiiich inner fkin, or rather mufcular part, covering the
tongue all over, is defended, as it were, by a thick external Ikin :
* The fame sjipearancc is noted by the author, when treating of the young plant ia the
Coifee-bean.
Ii2
( 258 )
this latter (kin is eafily taken off when a tongue has been boiled, or
has lain fome time in hot water.
This dii'pofition of the mufcles in the tongue is wonderful, and the
manner of their a6ling inconceivable by us, and dill more, with re-
gard to the human tongue, when we confider the variety of ways in
which the mufcles mud move and turn, to produce the effeil of
ipcaking, fmging, and M'hiflling, as before obferved.
The exertions of the flefliy mufcles in the tongue, are cliiefly pro-
duced by their afTuming a ftraight figure, or by being inflefted or
bent, contrary to the manner of the flefliy mufcles in other parts of
the body, (as far as has eome to my knowledge) for their contrac-
tion and cxtenfion, is produced by means of the multitudes of excef-
fively minute wrinkles or crimped up particles, of which eacii mufcle
confifts.
After this, I curforily examined the tongue of an hog, to fee, whe-
ther in it, the flefhy mufcles were intermixed or laid one acrofs an-
other, in the fame manner as I have defcribed in the tongu6 of an
ox : this I firft^ infpected in the thickeft part of the tongue, on the
upper fide, where it rifes in a ridge like a back ; and, I law not only,
that the mufcles were dilpofed in the fame manner as the ox's, but
that fome few of thofe which lay the lengthway of the tongue, in fome
])laces eroded each other ; the tranfverfe inufcles were the fame as
in the ox's. Searching farther inward into tiie thickod part, I there
faw many flefhy mufcles lying parallel to each other, lengthways in
the tongue; but no others lying athwart or eroding them. I alfo
bedowed fome invedigation on the thinner parts of this tongue, with-
out finding any thing worthy of note.
I have often employed my thoughts, on the formation of the flefliy
part in the hearts of animals ; not particularly to invedigate the courfe
of the flelhy mufcles, wl,ich I doubt not, has been iufficiently ex-
( 259 )
ainined and explained by olliers. And, thougli I determined, if I ihculd
obierve anything particular in tliat part of the iubje6l, to commit my
remarks to writing, yet, my principal obje6l was, to inveftigate the
formation of the very fmalleft flefliy mufcles, and to examine whe-
ther any thing might be found therein worthy of note.
For this purpofe, I took the heart of a flieep, but, with all my
pains, I could not fucceed in Separating or taking off' any flefny
mulde like that defcribed at fig. i^, NOPO, for, in the operation,
it was fo torn, and, fo many of the adjoining parts adhered to it,
that I could not then fatisfy niyfelf as to the true fonnation of fuch
mufcle ; nor with regard to the union or connedlion between it and
tlie adjoining parts.
After this, I tried the heart of an ox, cutting off many pieces, and
contriving every poffible means I could devife, to feparate a fmall
ilrip or oblong particle from the adjoining parts, but all to no pur-
pofe; and, at length, I found, that thefe flefliy particles v/ere fo
linked together, that it would be impoflible to fever them without
breaking.
This concatenaition, or linking together of the flefliy parts, (wliich
parts, in treating of the tongue, I have called minute flefliy mufcles)
in the fubftance of the heart, is of fuch a nature, that, at firfl, 1
defpaired of being able to reprefent it to the eye by any figure or
drawing ; but at lengtli, I fo far fucceeded, as to exhibit a reprefen-
tation thereof to the reader.
In thefe exj:;eriments, I tried the heart of a duck, in order to fee
whether its i'ormation, and particularly this union of the parts, agreed
with that of an ox ; and I found, that the flelhy parts in the duck's
lieart, were linked together in the fame manner as in that of the ox ;
and not only fo, but that I could better give a reprefentation of fuch
concatenation or linking, from the heart of the duck, than from any
of the other fubjedls I had examined : and thereupon, I delivered to
( 260 )
tlie Limner a microfoopc, ht^fore which was placed an exceeding
fmall piece of the flefliy part of a duck's heart, direcJ-ling liim to
make as accurate a drawing as poflible, of theobjedl wliicli prefented
itfch" to him.
F/ij. 14, ABCDEFGHIKLM, reprcfents tiiis minute particle
magnified, in vvliich may pkiinly be Teen, not only how evcrv
fingle flelhy particle is united or linked to the adjoining one, but
alfo, how all the flelhy particles, Ihewn in this figure, are con-
nected, chained or linked together.
As to the vacant fpaccs apjiearing in this figure, two of which
may be feenatBCD, and UNI, we mull not fuppofe, that the
fielhy parts are fo far aiunder as the drawing reprcfents, for I am,
fully perfuaded, that, when the heart is in its natural Itate, all tlie
flefliy particles of which it confilts, are fo clofe to each other, that
nothing but an exceeding thin membrane intervenes, within which
membrane the blood-veflels take their courfe ; and there alfo, may
fometimes be feen particles of fat, ei'pecially where the blood veiVels
are larger than ordinary.
Farther, I always obferved, not only in tlie hearts of an ox and
flieep, but alfo in that of a duck, all the flelhy particles, which,
when defcribing them mfig. 13, I have called mufcles, but which
I cannot here call by that name, becaufe they are not enveloped by
membranes peculiar to themielves ; thefe particles, I fay, whicii
in fig. 4,, are exhibited at LM or AB, I found, again to confift of
great numbers of flender oblong particles, which often leparatcd
from each other, and at little di Ranees united with other particles :
but thefe fmaller particles are not reprefented in the figure, becaufe
they had become ib dried, as not to be viiible to the Engraver.
\\c may now figure to ourfelves, that the particle of flefli, which
^g. 4, exhibits at A B, again confilfs of an hundred and more oblong-
particles, and, that a little above A B, they arc divided into four
( 2(Sl )
parts, and thefe parts, again united with other flefliy particles.
But how often this feparation and reunion of parts take place, and
what courfe the particles themfelves take, 1 have not yet been able
to difcover.
Each of thefe feveral flefliy parts, of which only two are exhi-
bited in^^. 4, at BCD, and HN I, were covered with broken and
torn fragments of other parts, but thefe I direiled the Lim!ier not
to delineate, that the concatenation, or the manner in which the par-
ticles are linked together, might be better diftinguifhed.
After I had cauled the before mentioned drawing, fig. 14, to be
made, I again examined various flelhy particles in the heart of a duck,
and, while I was thus eni])loyed, I met with one fmall piece, in
\vhich I was convinced, that the concatenation or linking together of
the parts, would be flill more difl:in(5tly feen. This, being placed
before a microfcope of fomewhat lefs magnifying power, I delivered
to the Limner to make a drawing of.
Fig. 15, ABCDEFGH, is this piece of a duck's heart, in which,
more plainly than before, can be feen the nature of its formation,
which will appear iViU inore wonderful, if we confider, as the truth
is, that the conne6lion or linking together of the parts, in the particle
which this^^. 15, rcprefents, was, in the fubjeft iti'elf, thrice as much
as here expreffed ; for, I could not feparate a piece of this fize from
the heart, without tearing afunder twice as many parts or points of
union as are here exhibited. This particle was taken from almofl: the
outfide of the heart, and, that part which in the figure is marked
ABCD, was fituated pointing towards the fmall end or tip of it.
In order to Ihew the true dimenfions of the particle reprefented,
in this lall figure, I meafured it, and found, that the whole length ihewn
in the figure, between the letters EFG H, was, in its natural fize, not
more than two third parts of the breadth or thicknefs of that part
( 26"3 )
which, in the iigiirc, appears between the letters G and H, or, the
lize pii^tured at X.
Seeing now, that tills flediv particle, though noi; in fa6l, larger
tlian the fpace between G and H, or at X, does yet confjfi: of more
tlian an hundred dillinct oblong particles, as I can affirm from the
molt exa(il: computation of my own view, and. that this is not
only the cafe, in the heart of a duck, but alfo in that of an ox ; and
moreover, that each of thofe (lender, ob'ong, component j)articles,
again confifls of a great number of excelJivcly minute particles, we
(hall more and more be ftruck with wonder, at tiiis formation of the
lieart. And who can tell, into how many I'mall particles, entirely
undiicoverable by us, thefe lait named particles may be again divided ?
We find, that in the commoji mufcles of the body, thofe fmall
mufcular parts, which conftitute a large mufcle, may be feparated
from the larger one, often without tearing the oblong flefhy
parts which compofe it, nothing being broken, except the thin mem-
brane with which the fmall mul'cular jjarts arc, as it were, enveloped ;
for, all tliofe (lender, oblong, flclhy parts, lie difpofed in regular pa-
rallel order, befide each other ; and, at th.eir extremities, are united
to a membrane which furrounds the mufcle, or, rather, forms the
tendon of that mufcle, which in faft the membrane does : hence we
may eafily comprehend, that, when any part of a common mufcle is
wounded, the part which remains uninjured, may (till, in fome de-
gree, perform its funcStions ; becaufe, as I have before laid, the fmall
mufcles which compofe a larger one, are only connec^^ed by a kind of
membrane : but, on the contrary, when any one particle in tlie
ilelhy fub(hincc of the heart, inch as is reprcfented in j^V. Tfy at
A BCD, or any other particle though much mere minute, is wounded,
the whok\flefli or fubltance of the heart, (by reafon of the intimate
union of its parts) not only firiiers, but, through the violent and con-
liiiual agitation of the heart, in the protrufion or expelling the blood
3
(^^63 )
hi circulation, it becomes weaker, and, from fo fmalla wound, death
mufl; enfue. Moreover, wlien I confider, how often we find a fmuU
exulceration or fore, in the hand, finger, or other part of the body, of
wliich we caiuiot perhaps trace the caufe, I can eafily conceive, that
a fmall exulceration may, by fome accident, happen in the heart,
whereby fome of the flelhy particles may be injured, or rendered
incapable of performing their fun6tions ; whence the lieart not only
languilhes, and becomes feeble, but, at length, may ceafe to mo*'e,
whence fudden death enfues : and the Phyfician, not knowing the
real caufe, is led to pronounce, according to the common opinion,
that the perfon died of an apoplexy. Thefe are, however, no more
than my own conie6lures.
From what I have advanced, it may naturally be concluded, that
I Ihall farther lay it down as a certain pofition, that the heart cannot
luft'er any wound, without certain and immediate death being tlie
conlequence : this, however, is not my opinion, in all cafes whatfo-
ever. For, we know, that there are many veins between the flefliy
parts in the infide of the heart, which take their courfe from thence,
and unite with the blood veflels furrounding it on the outfide ; which
blood veflels, are, throughout, and efpecially on the outfide of the heart,
covered v.ith fatty particles ; i'o that there maybe inftances, where the
very extremity or point of a fword, may penetrate into the heart it-
felf, but, being in a part where thofe veins and particles of fat lie,
none of the flefhy particles of the heart may be injured, and the vein
and fatty particles alone receive the wound, together with the exter-
nal membrane furrounding the heart : hence it will follow, that fud-
den death may not in fuch a cafe enfue.
After this, I examined the heart of a hen, in which alfo, not with-
out pleafure, I faw the concatenation or linking of the flefliy parts,
to be exa61:ly the fame as in the other hearts I have mentioned.
This, however, I obferved in tlie hen's heart, that, when cutting
Kk
( 2^4.)
it longitudinally, tlicre appeared Ibmc diiTerence in the formation,
for, whereas the cavity in the hearts of oxen and fheep, is provided
v*ith a tendon ; on the contrary, liere, inl^ead of the tendon, I
found various flefliy parts, with their ramifications, fpread over the
cavity of it. Whereupon, I began to refle6l on the great exertion,
wliich birds are obliged to ufe in flying, and how little they are fati-
gued, even after taking a long fliglit. But, to fay any thing fatisfac-
torily on this head, many previous obfervations ouglit to made.
Afterwards, I examined the heart of a cod fifh, and found its com-
ponent parts linked together in the lame manner as I have defcribed
thole of the other animals, and of the duck, to be : but when I re-
fle6led on the circulation of the blood through this heart, (which ap-
peared more of a flelliy than a fifliy nature) and confidered, how the
blood is propelled from it, into a white body, in folidity or denfity
nearly equal to the heart, whofe ])articles are linked together in the
manner I have defcribed, and to how great a degree thefe particles
upon the infufion of the blood muft be extended, and how contracJkd
in its propulfion, I was more and more loft in admiration.
On the eye of a JFhale, zvith the Author's obfervations oft the prejfurc of
the fea-zvater at great depths.
X HE mailer of one of our Greenland fliips, by name Ifaac van
Krimpen, upon a certain time, made me a prefent of the eye of a
Whale, prelerved in fpirits of wine. This eye was not of a perfectly
ipherical figure, for its axis, in the thickefi: part, was two inches and
ieven-tenths of an inch in length, and the axis in the thinnelt part
was not longer than two inches and an half.
That part of the tunica cornea in front of the eye, wliich rifes in a
globular protuberance, was two inches and an half in diameter.
The cryflalline humour was not quite of a circular figure, as we
generally find it to be in fifhes ; but on one fide, its fliape was fome-
wliat depreiTed, and the axis thereof meafured feventeen thirtieth
parts of an inch, but the axis of that part which was extended to-
wards the objecl of vifion, was about half an inch in length.
Tlic cavity, wherein the crylialline humour is included, was al-
mofi: two inclics diameter. The fubflance conflituting the furface of,
and furrounding that cavity, was lb compact and ftrong, that t
was fcarcely able to cut it with a very fliarp knife.
Obl'erving this, I began to confider, whether the nature of this
filh did not require, that the fubftance inclofing the cryflalline hu-
mour, fliould be fo hard and Iblid , becaufe a Whale fometimes dives
to great depths in tlic ocean, and, as the fifli under confideration,
had run out the length of fourteen whale lines, each of wiiich is
Kk 2
( 266 )•
an hundred fathoms long; and, in this deptli of fca, the prcniire
of water on the bottom, is much greater than is commonly ima-
gined.
For, fuppofing the ocean, in any given place, to be 1400 fathoms
deep, and each fathom to contain fix feet, which is the common
meafure, it follows, that the ocean is, in luch a place, 84,00 feet deep.
It is well known, that a cubic foot of water, fuch as is found in our
canals, weighs 6g jwunds, but that the fame quantity of fca water,
being in its nature heavier, does not weigh lefs than 66j; pounds ;
but taking it only at 66 pounds, the refult will be, tliat every cubic
foot of fea water, where the ocean is 8400 feet deep, does jjrefs on
the bottom with the weight of 554,400 pounds. And, with regard to
the whale lines, wiiich I have faid are 100 fathoms long, I am told
that they are more commonly 120 fathoms, which gives a deptli of
16,080 feet.
The fame Captain Krimpen, in a fubfequent converfation informed
me, that this Whale, having run out the length of fourteen lines, lay
on the fandy bottom of the fea at that depth, from whence it was
weighed up or raifed by means of the windlafs, and he added, that he
fliould not have fucceeded in getting up this fifli, unlefs the line,
which by the harpoon iron was fixed in it, had alfo got a turn
or two round the tail, by which means, the Whale was brought up
to the furface, the tail foremofl.
The weighing up this Whale, was atfirfl fo difficult and laborious,
that fix men at leafi, were necefiarily employed in heaving at the
windlafs, and no lefs than fix hours were fpent in the operation.
But, when all the lines lave one, were hove in, the labour became as
nothing ; for which latter circumftance, I afilgned to Krimpen, this
twofold reai'on, that the prellure of the water on the Whale was then
greatly diminiflied ; and, that the filh abounding with oily or fatty
parts, which are lighter than water, would have a tendency to be
buoyaiit. 1
( 267 )
Let us now fu])pofe, the eye of this Whale, in tliat part of it which
was expofed to the fea water, to contain fix fqiiare inches in its fu-
l)erficies, we may juftly fay, that when the fifli defccnded to the
depth of lea we have mentioned, the prefllire on its eye mufl be
equal to 23100 pounds weight. For, fix fquare inches are tlie
twenty-fourth part of a fquare foot, and, if the prefl'ure on a fquare
foot, at the before mentioned depth, is 5541,4,00 pounds, it follows,
that the twenty-fourth part, will fuftain a preflure of 23100 pounds,
which is one ton, fix hundred, and a quarter of a hundred weight.
Seeing then, that fix fquare inches of fpace, at the bottom of the
fea, where it is 8400 feet deep, do endure a prefllire of water equal
to 23100 pounds weight, it is no wonder that the fea in the Bay of
Bifcay is not to be fathomed by the lead. For, if the fea water, at
the depth we have mentioned, prefles on tlie bottom with the weight
we have computed, it follows, that in fome parts of the ocean, whicli
are at leaft eight times that depth, the prefllire mufl: be eight times
as much. •
Hence we may fairly infer, that a weight, altlioughof lead, fuch as
that which feamen call the deep-fealead, cannot, where the depth is
fo very great, touch the bottom, or at leaf}:, not in a manner to be
perceptible, not only on account of the very great preflure on the
lead, but alfo, on account of the much greater j^reflure on the lead-
line, by reafon of its great length, which line itfelf is not mucli
heavier than the fea water ; fo that the prefl'ure may very naturally be
iuppofed to prevent the lead reaching the bottom. Again, it muft be
confidered, that the ocean, though no current may be vifible on its
furface, yet is never at reft ; fo that though the lead, when caft,
feems to fink ftraight downwards, yet it may be carried away by
fome fubmarine current, far from the man who heaves it, and the
line may be bent and twifted many ways, by all which means, in
fuch great deptlis, the lead may be prevented frosn reaching the bot-
tom. But to return,
( 268 )
The cryftalline humour in tliis eye, was fo clofely joined to the tu-
nica cornea, as to force it out into a kind of globular extuberance or
rihng, which appearance I'eemed very flrange to me, having never
obferved the like, in any fifh or animal.
I took ofFa piece of the tunica cornea, rather more than an incli in
diameter, and, after leaving it a while to dry, I cut it by an oblique
incifion into flices, in order to count, with greater facility, the num-
ber of thin membranes of which it was compofed, and I found, that
it confifted of, at leaft fixteen or eighteen of thofe thin membranes,
laid one on another.
This tunica cornea, was lined on its infide, with a black membrane,
every where entirely impervious to the light, excepting an oval aper-
ture immediately in front of the cryftalline humour, through which
the liglu was tranfmitted ; this alfo was to me an unufual appear-
ance. This oval aperture was in length half an inch, and in breadth
fomewhat lefs than a quarter of an inch.
From this laft obfervation, a thought occurred to me, whether the
whale has not a power of enlarging and contra6ling this aperture at
j)leafure, fo as to alter the manner of its vifion, as occafion may re-
quire. The fame power of dilating and contracting the pupil, I re-
member to have obferved in the eyes of a cat.
I then employed myfelf, to extra<51; the membrane which covers
the back part o^ the eye, and to examine the optic nerve ; this I
found to be no larger than the optic nerve in the eye of an ox, but
I noted this fingular circumftance attending it, tliat inniany places,
and I eafily counted as far as twenty five of them, I law adhering to
the membrane, arteries and nerves, which ifllied from the part
through which the optic nerve palles. Some of thefe, were about
the fize of a common pin, others much larger.
Thefe are the matters, which appeared to me worthy of note on tliis
occafion, though, if it were pofliblc to obtain the eye of a \Miale when
( 2^9 )
newly taken out of the head, I doubt not, that our enquiries might be
profeculed much farther, and that, confequently, greater fatisfaftion
miglitbe procured in the inveftigation.
If we con fider the propagation of the Whale, by comparifon with
that of the fmaller fifli, we fliall be led to admire tlie wife difpofition
of Nature in this refpe(51:. To initance in the common Ihrimp ; every
one of them may be denominated a female, for they all, without
exception, propagate their fpecies by eggs ; and that, in fuch
numbers, that once, when I began to count the eggs on one
jhrimp, I liad not got halfway through the mafs of tliem, before I
was tired, and gave up the attempt. Such a vaft number of eggs,
produced by one fmall fifli is wonderful, efpecially if we confider,
that every one of thefe minute eggs is nourifiied by a blood vefld.
Now the larger fifli, which devour the fmaller, fuch as the Whale,
the porpoife, and the iword fifli, are not propagated by eggs, but
bring forth their young perfe61:ly formed ; for if thefe kind of fifli
increafed fo abundantly as the others, the fmaller fifli would every
one be devoured by them.. The Whale in particular, brings forth
only a fingle young one at a tisne, and is jjrovided with two breafls
filled with milk, and fuckles the young, after the manner of terref-
trial animals.
I have Ibmetimes, when reflefting on the enormous bulk of tliofe
Whales which were taken at the beginning of the Whale filhery, and
on thofe huge bones of Whales, which are in many places fixed up
for public view ; I have, I fay, on thefe occafions, conje6tured, that
probably thofe Whales might be of the age of a thoufimd years and
upwards. . For I am perfuaded, that fiflies never die of old age, for-
afmuch as their bones, being always of a foft texture, which never
grows hard, may always be extended, fo that the fifli themfelves
are always growing larger. But, terrefirial animals are expoied to
the changes of the atmofphere, whereby their bones grow hard, and
( 270 )
when the bones are hardened, the body of the creature cannot be ex-
tended to a larger iize.
Having once, with the afllftance of an able geometrician, and by
tlie eye with the help of quadrants, meafured the height of the tower
of our new churcli in Delft, we found it to be 299 feet.* So that the
depth of the fea, to whicli the Whale I have mentioned defcended,
was twentj^-fix times as much as the height of that tower.
* The London reader will be better able to judge of thcfe altitudes, (the word altitude
taken in the fenfe of the Latin, althudo^ from which it is derived, fignifies both height and
depth) by comparing them with the Church of St. Paul's or the Monument : the former of
thefe is about 500 feet in height, and the latter 200 ; fo that if we call the height of the ftecple
at Delft 300 feet, the Church of St. Paul's is two thirds higher, and the Monument one
third lower than that fteeple. And the depth of fea from whence the Whale was raifcd, was
equal to forty-two times the height of the Monument, and more than fixtcen times the height
«f St. Paul's.
Of the Qiiills ufed in writ'mg, and their feathers : on human hair, and
the hair and xvool of anitnals.
IVJ. Y reflexions on the nature of thofe Quills with which we w'rite.
as alfo on the general make of the feathers of birds, led me to an
inquiry into the manner of their formation ; which at length I dif-
covered, and found, that Quills are compofed of frreaks, or more
properly fpeaking, veflels. Thefe vefl'els, in every Ouill, are three-
fold. The firfi:, or external ones, w-hich conftitute but a fmall part
of the Quill, are parallel to its length: the fecond, which are
in a much larger quantity, take their courfe round about the
Ouill, wiuhin the former ones : thel'e fecond fort of veflels are not
fo clofely united as to form what may be likened to a folid body, but
lie one on another like fcales or coats, in fuch manner, that the dif-
ferent la}'ers of them may be plainly perceived : the thii'd fort of
veflels, which compofe the thickefl or greateft part of the Ouill, lie
lengthwife, in hke manner as the firfl; mentioned ones : this third
fort of veflels, are alio difpofed in the manner of fcaly parts laid one
on another ; and, confldering the thinnefs of a Quill, and the large
cavity it contains, its formation is, in my judgment, the ]nofl perfe6t
that could be contrived ; for, hereby it is made tough and ftrong,
both in its circumference, and in its length. To exhibit the nature of
it to the eye, I caufed a drawing to be made of one.
In Plate IX. fg.i, ABCDEFG, reprefents a common gcofe
LI
( 272 )
Ouill, drawn fmaller than the natural fize. AtABG, are repie-
il-ntcd thofe veirels which compole the external part of the Quill, and
lie in it longitudinally ; BCFG, are thofe which take their courfa
round about it ; CDEF, are tlie veflds, which, like the firll'men-
tioned ones, are placed the length way of the Ouill.
From thel'e obfcrvations, I difcovered the reafon, why fome OuilJs
when they are fplit lengtliwife, in that j)art where tliey are hardefl,
form a kind of indented or jagged part in the filfure ;* namely, be-
caufe thofe velTels, whole courfe is round the Ouill, are not all
broken in an even ftraight line ; efpecially, as I laid before, where the
Quill is liardefl : and where thefe vedels are heaped together in greater
quantities than in other parts. Therefore, to prevent this accident,
wlien the Quill is fo very hard, it is neceirary to fcrajie it a little
with the pen knife, by which means, in the fplitting, it will be llraiglit
and even.
I have frequently, by tlie microfcope, contemplated that part of thefe
Quills which is called the feather, and alfo the feathers of fmall birds;
and always viewed them with admiration ; not only on account of
the multitude of parts to be feen in them, but alfo, by reafon of tire
great numbers, and extreme minutenefs of the vellels, of which, not
only the whole featlier, but every little part of it is compofed.
To exhibit to the view, the great numbers of vefiels of which tlie
feather conlUls, I placed a fmall piece of one before a microfcope,
and a drawing of it is given ^tfig- 2, LMNOPO.
In the preceding /^. 1, DHIKE exhibits part of the feather of
the common writing Ouill, fmaller, as before obferved, than tlie
natural fize. At K, is reprefented a fmall part of the feather, a piece
of which, i'een by the microfcope, is fhewn ^tfg. 2, for, if thewiiolje
* This mod commonly happens in thof: Q^iills which have not been, what is' called
clarified, or when the Qviill is fplit near the feather; this jagged fhaps of the fplit is w^Ui
known to fchool boys, and is denominated by them, cats teeth.
( 273 )
of this piece Avere to be drawn when magnified, it would appear laro-er
than the whole feather, feen by the naked eye. When this fmall
part of the feather is viewed by the microfcope, it will appear, how
every one of its parts confifls of a great number of fmaller feather
ihaped parts, all which parts are lb conne6led or knit together, as to
give flrength to the whole feather.
The reader, liere, muft underlland, that the particle or piece
which is Ihewn magnified at ^f^. 2, LMNOPO, is not, in fa6l, fo
big as a large grain of faiid : and further, that this particle received
nourilliment in its growth, no otherwife than by fmall veiTels : the
reader alio ^^ill advert tojjg. 3, RS, which is drawn from a micro-
fcope of greater ]iiagnifying power, and is flripped oli from the fide of
fig. o, at MNO, and alfo tofg. 4, TV, v/hich is taken from the fide
of>V. 2, at OPO.
AtLMO, is reprefented a part, bearing the appearance of glo-
bules, of which the interior fubfi;ance of this fmall particle of a fea-
ther is ccmix)fed, which agrees with the formation of the correlpond-
hig ])art in the entire feather of the Ouill, pictured aty^'-. i .
In the figures 3 and 4, by R and T, are reprefented fbme fhiall
veflels broken or torn afunder.
All thefe fmall particles, each of which may be called a minute fea-
ther, not only lerve to give ftrength to the whole feather, but are fo
contrived, that in the bird's flight, thele particles remain fo clofely
joined together, as to enable it to make a flrong imprefllon on
the particles of air, b}^ the exa6t and regular order of the component
parts of the feathers. For otherwife, birds would not be able to fup-
port themfelves in the air. All thefe particles, as I faid before, lie
in moft exa6l order befide each other, which has induced me
frequently to contemplate them, as alfo on account of the innumera-
ble multitudes of veflels of which the Ouill confilts.
From this inflance, in the formation of the feathers of birds, we
LI 2
( 274 )
may obl'erve, that provident Nature, if not in all, at leaft in many
things which come under our hiveftigation, performs her operations
with the greateft uniformity ; for, in like manner, the cryftalline hu-
mour of the eyes, not only of men, but of the larger terreftrial ani-
mals, and alfo of fiflies, as far as I have examined into them, con-
fifts of a kind of fcaly parts, laid one on another : fo likev/ife the tu-
nica comea or horiiy coat of tlie eye, which coat, I at firfi: conceived
to be compofed of only three diftin6l menibrancs, but afterwards, on
a more accurate invefligation, 1 found to confift of an hundred
membranes, laid one on another like fcales. And I conclude that
this formation is defigned, not only to give the coats of the eye a
great degree of ftrength and firmnefs, but alfo, that if one of the
membranes fhould be hurt, the others may el'cape uninjured.
It is the opinion of many, that the hairs on the bodies of men and
animals, are hollow, and fome think, that they contain in them a
marrow like tlie bones ; but thefe opinions are erroneous. Hairs
are formed with a kind of coat, which is analogous to tlie bark
of trees, and their internal fubllaiice confifts of ftreaks or fibres.
Their growth, is not like that of plants, but is produced by a
kind of propulfion, that is to fay, that the part which one day
is within the Vtun, and is as it were, the root, in a day or two,
is thruft out beyond the Ikin : and as, when the hair firfl comes forth,
it is, in all its parts, very moift, as foon as the moiflure begins to
evaporate, the coat or bark of the hair, and the fibres adjacent to it,
acquire a degree of firmnefs which prevents the hair from contra6iing
inwards, whence it comes to pafs, that, as the internal fibres continue
to dry, and thereby become thinner, they are divided afunder, and
recede from each other, fometimes forming one, and fometimes
more chinks, exhibiting a kind of darkifli furrow or furrows, v>hicli.
( 275 )
doubtlefs, is what has been taken for the marrow of the hair. All
this will be better underftood from the following figures.
Fig.g, ABCD, is a piece of an hog's briltle, which I cut by a
tranfverfe feclion ; EEEE, are the chinks or cracks, arifing from
the drying of the hair as above mentioned, and this hair is burft or
cracked, in the infide, more than ordinary. Fig. 6, FGHI, is a
piece of the fame hair, fomewhat nearer the fkin, alfo cut tranf-
verfely, in which, there are not many cracks, or chinks, but only
one, which is, however, fo large, as to exhibit the appearance of
a hole or cavity in the hair, as appears at KLM, and any one, upon
feeing fuch an hair as this, would certainly conclude, that the ca-
vity here feen, was not accidental, but the natural form and make,.
and confequently, that all hairs are hollow. Fig. 7, NOPO, is an-
other piece of an hog's briftle cut tranfverfely, from which I fuppofe
the moifture had evaporated lb flowly , as not to leave the leaft appear-
ance of a chink or crack : Jig. 8, is a perfe6tly black hog's brillle cut
tranfverfely, and, as it exhibited a pretty appearance, I have given
a drawing of it. And, though the roughnefs, which is on the eds^e
of the iharpeft razor, frequently leaves fcratches on the face of the
hairs thus cut tranfverfely, I almoft wholly avoided that appearance,
for which reafon, I was better able to point out the flreaks or fibres
of which the hairs confift.
From the preceding figures, it will appear, how much thofe are
mifiaken, who will have it, that all hairs are round, whereas we ought
rather to fay, that every hair has a figure peculiar to itfelf.
It is my opinion, that the hairs on man's body, do, at certain fea-
Ibns, fall off, and are again renew^ed, like the feathers on birds ; at
leaft, I have experienced this to be the cafe with myfelf every fpring,
(excepting the hairs on my head and beard) and I have obferved,
that thofe hairs which feemed ready to fall off, coujd be pulled out
with a fmall pair of pincerS;, and not caufe that pain which attends
( 27G )
the plucking out a Iiair tliat h firmly fixed ; aiiJ I iiavc farther
obfcrved, that thofe hairs wliich are pulled out by force, have large
thick roots, whereas, the roots of thofe wlVich are near falling oH",
are very fmall and pointed.
Fig. 9, A13CDEFG, and HLMNPO, are tv.o very fmall hu-
man hairs with their roots ; in tliefe will be fecn, that the points or
Imall ends of them, at G and O, are fomewhat bent, which I attri-
bute to this, that the points, when tiiin and tender at their firll ex-
puifion from the Ikin, had met with iome obftacle in their growth,
which not being able to penetrate, they were bent obliquely : It is
not iifual to fee hairs bent at the fmall end, in the m.anner Ihewn at G,
but tliey moil commonly appear as at Q.
AB, and H L, are tlie roots of thefe hairs, which do not appear
ib large, if tiie hair falls off of itfelf, but, when a hair is pulled out by
force, the root appears much larger tlian the hair itfelf, as is Ihewu
in this figure.
The bending of the hairs I have noted above, may very eafily be
occahoned by their meeting with fome obftru6lion in their growth,
and having obferved a hair on my arm, wliich was very much bent,
i pulled it out, and placed it before a microfcope, in order to (hew
its figure in a drawins".
Fig. lo, ABCDEFGHI, exhibits this hair, in which, ABC is tlie
root, and at AC may be leen a fmall portion of the cuticle or outer
Ikin, which adhered to tlie hair. DEF, indicate a confideruble bend-
ing in the hair, and at GEH is Ihewn a much greater bending, or
rather, an entire circular curve.
I have faid, that hairs are covered with a coat or bark, in like
manner as trees, and that, however fmall, tliey are compoled on the
infide of oblong parts or iibres, and I ajn perfuaded, that there is no
difference between iheep's wool, whicii is the fmalleil: kind of hair,
and the hairs of men and animals, except, that (beep's wool confilts
5
( 277 )
of a lefs number of internal fibres. In order to fatisfy myfelf in
this refpe(^i, I often broke pieces of wool, and endeavoured to
fplit them into fmaller parts, wherein at firft I was unfuccefsful, but
at IcuiTth I found means, not onlv, dirtin61:ly to lee this formation
myfelf, but alfo to exhibit the fame to the view of others.
I therefore delivered to the Limner three micro fcopes, directing
him, to make drawings of the obje6ts he faw.
Fi^. 11, KLMN, reprefents a fmall piece of white fheep's wool,
m which, at L and M may be feen, that it confifts of a great num-
ber of fmaller hairs, (if we may call the interior parts of the v.'ool by
that name ;) and who can tell, whether each of the particles, fliewn
at LM, may not again confilt of a great number of ftill fmaller par-
ticles ?
This piece of white fheep's wool, was very tranfparent before it
\^as broken, or cracked ; but, at L and M, where many of its oblong
component particles are broken or fevered ai'under, it appeared quite
opake, and more of a black colour than tranfparent.
Fig. 12, OPO, reprefents a piece of white wool, placed before
another microfcope ; this piece is broken or burft open only in one
place, where alone the internal parts appear, and at Q only two of
thofe internal parts can be ieen, whereas, in the piece pictured at
fg. 11, all the internal fibres are divided afunder.
Obferving one of the hairs on my arm, to be not only much
broken or worn away, by the friftion of my fliirt, but alfo the inter-
nal parts to be feparated from each other, I pulled out the hair, and
placed it before a microfcope : this piece of broken hair, magnified,
is reprefented ztfig. 13, RS., wherein at S, which is the part worn
or fretted away, Ibme fmaller particles appear, being the fmall fibres
cf which the hair confifis.
The preceding experiments and obfervations, will, I truft, refute
the erroneous opinion I have mentioned, that the hairs, on our bodies
( 278 )
are hollow within, and, if hair and wool, (which is the hair of fheep)
were not compofed of many minute hairs or fibres, they would not
have that ftrength and toughnels which we obferve in them.
Sometimes, in human hairs, and efpecially in the very middle
of them, I have obferved a dark line : particularly in feveral of the
hairs taken from my own beard: and when I attentively exa-
mined this dark line, I found it to confift of fuch minute and flender
particles, as to be almoft undifcoverable even by the microfcope.
Examining fome very fmall hairs, of three, four or five days
growtli, and finding fome to be throughout quite tranfparent, others
darkened only in a very fmall degree, and finally, others with no
more than a fmall dark i'pot on them, I began to confider, whether
this dark Ihade in tlie hairs, might not proceed from fome particles
of blood in the fabftance of the hair, and there dried.
To give the reader an idea of tliis dark line, I caufed a drawing to
be made of a piece of a fingle hair, which I concluded to be of liiree
days growth ; this is to be feen 'dtfg. 14,, O P()RSTV W, in which
at (^RS and V WO, are the two ends where tiie piece of hair was
cut with a knife : from W to P, or as far as T, the dark line I have
mentioned extends, wiiich I have mentioned to be vifible in fome
hairs, and in others not fo confpicuous. Laftly, between R and
T P are reprefented thofe dark fpots, which are to be obferved in
other hairs.
The translator, to the READER.
j[F this tranflation is a faithful one, I doubt not that the Reader will
be led to admire the extenfive range of the Author's refearches, and
the pains he takes to make his difcoveries intelligible to all ; and
thofe who compare his defcriptions with the produ61ions of Nature
at this day, will be equally pleafed to obferve their exa6l coinci-
dence.
But, though I think it may fairly be faid, that the works of Mr.
Leeuwenlioek are, upon the whole, fuperior to any that have appeared
upon Microfcopical fubjefts, I do not mean to fay, that there are no
inftanccs, in which others have not been equally fuccefsful. A coun-
tryman of our own. Dr. Robert Hooke, who was a cotemporary of
the Author, and Secretary to the Royal Society loon after its firft
inftitution, publifhed feveral ElTays, containing his difcoveries by the
Microfcope, with inany very judicious and ufeful remarks. In fome
of tliel'e. Dr. Hooke has handled the fame fubjeils as our Author,
and I fliall take occafion, here to introduce a pailage from that Book,
wherein fome of the particulars refpedting Feathers, mentioned in
the preceding Eflay, are more minutely defcribed than by Mr.
Leeuwenhoek. *
" Examining feveral forts of Feathers, I look notice of thefe par-
" ticulars in all forts of wing-Feathers, efpecially in thofe which
*' ferved for the beating of the air in the ac^lion of flying.
" That the outward furface of the Quill and ftem was of a very
" hard, ftifF, and homy fubllance, which is obvious enough, and
" that the part above the quill ^\'as filled with a very white and light
" pith, and, with tlie microfcope, I found this pith to be nothing
f eife but a kind of natural congeries of fmall bubbles, the hlms of
* Hooke's Micrographia, p. 165, Edit. 1667.
M m
( '-5^0 )
" \vhicl\ fcom lo ho of the lanie t'ublhincc with that of th.c quill, that
*• is, a iVitV tnmrivuvnt honu fublhuKo.
" As for the make aiul contoxturo of the downi itfolf, it is indeed
" very rare and admirable, ami fiioh as I can haixlly believe. tli.-it
•' the like is to bj difeovered in any other body in the world ; for
•* thctv is h.ndlv a larjio Feather in the wini): of a biixl, but contains
" near a n\illion of di It ini"-t parts, and every one of them niai)ed in
" a mofl ivc'ular and admirable form, adapted to a particular dcfign ;
" for, exainininq; a mid.lle fi/.ed goofe quill, I oalilv enouv;h founil'
•* with mv naked eve. that the nuiin Hem of it contained about <oo
*' longer and moiv dowtiy branchinajs uixm oik* Hde, and as many on
" the other of moiv iVilVbut fomewhat Ihorter branchings. Many
'* of thefo long and downy branchings, examined with an or-
•* dinary microfeoiv. I fv utul divers of them to contain near 1200
•' fmall leaves, ^^as I may c;ill them) fuch as KF in the figure*
" and as many fhilks : on the other fide, fuch as IK in the fame
" fijruiv. each of the leaves or branchings. EF. feenKxl to be di-
** vidotl into about fixteen or eighteen fmall Joints, as may be feen
*• plainlv enough in the fig\nv, out of molt of which theiv feemed
'" to grow fmall long fibivs. fuch ai! are expixMlWi in the figinv, each
" of them very piv'ivrtion.ibly fl\a|x\l accoixling to its jx^fition, or
" placed oi\ the llalk F. F ; thofe on the under lido of it. namely,
*' 1. ^^.,s..V-o*^"-7''^>^-' ^*'- being much longer than thofe diret'^tly op-
" |H>fite to them on the up|KT ; and divers of them, fuch as 3.^.4,5.
" o\ 7. S.Q, ^c. wcix" terminatevl w ith fmall crooks, much lefem-
•• Ming thofe fmall cixniks, which ai-e vifible enough tx> the naked
" c\e, in the iVvd- buttons of buixWks, The Italks likewife, I K. on
" the other fitle. feemevJ divider! into near as nianx fmall knotted
"joints, but w ithout any apiKXuance of firing's or cixvks. each of
** them aKnii the middle K. ftx:med dividixl into two parts bv a kind
( 28i )
' of fork, one I'ulr ol" wliii'li, namely, K T., \v;is oxioiuK-d iu\u- ilu*
' loMi;th (>(' KI, tlu" otluT, M, was vtM-y (liort,
" riu" tranlVci'lc I'oiMions of the (IfinN ol tlu-l'e br,iiuirnu;s, in;iiii
' reded (ho lliapcor li<;ui'eol' it (o he mm h Iik(> IN Ol',, wiiich (oii-
' lilk'd ol' a horiiv Ikiii «)r covorins;', ami a white UH-mmi;lv liolliv
' j)ith, mucli like the make of ihe main liem of a I'ealher.
" Tlie liems ol" llie (k>\\nv hranehes INOh', hriii>;- rammed in the
' order vilihle eiKHioh to the naked eye, at the dillaiieo ol' I I'", or
' Ibmewhat more, the eolhiteral llalks and leaves (ifl may I'o call
' iholb hollies 1 newly delerihed) are lo ranged, that the leaves or
' luiiry llalks of the one lide lie at to]i, or are inenmheni on tlu-
' (hilks oi" the othei', and erofs each other, mneli alter tlu-
' manner exprelled in llu" lit;"iire, * hy which means e\t'r\' one ol
' thole little hooketl lihres ol' the leaved lialk <.>;els hi'twcvii the
naked llalks, and the llalks heint'; full of knots, and a pi'etty
'way disjoined. To (hat the lihres can ealily j;"et between (hem,
' (he (wo ]iarts are I'o clol'idy and admirahly woven (ogether,
' that It is al)Ie to impede, I'or the grealcli jKirl, the Iranrtan'rion ol"
* the air ; and thouj^h they are \'o exceedingly Iniall, as that (he
' thitkiu'ls of one or.diel'e llalks amounts not to a _'-,oolh pail ol' an
' inch, yet do thev eompol't- To liroii'j^a tt-xtiiri', as. no(\\ ithllanding"
' (he exeeediiiL;" (]uick and violent heatiiii^ ol' tlu'in ai;ainll the air, hy
' the (trength of (he bird's wiiitj;, (hey firmly hold (ogether. And it,
• argues an admirable providence of Na(me in the contrivance and
' fabrick of (hem ; for their tex(ure is fiich, (hat though by any e\-
' ternal injury (he j^arts of (hem are violently disjoined, I'o as (hat
' the leaves and llalks (ouch not oni> another, anti eonle(|ueii(iy Iv-
' veral of ihel'e rents would impede the bird's Hying; yet, for (he
' molt part, of liiemfelvcs they readily re-join and re-oontcx tlicni-
* Pl.itc IX.Jii;. 1 6.
M m a
( 282 )
" felves, and are eafily by the birds ftroking tiie Feather, or dravv-
" ing it tlirough its bill, all of them fettled and woven into their for-
" mer and natural pofture ; for there are fiich an infinite company of
" thefe fniall fibres in the under fide of the leaves, and moft of them
" have fuch little crooks at their ends, that they readily catch and hold
" the flalks they touch."
Here we fee a perfe6l agreement between thefe two valuable wri-
ters, in defcribing the fame fubje6l, with this difference only, that
the Englilh author has more minutely defcribed that curious part
in Feathers, which Mr. Lceuwenhoek only mentioned flightly ; I
mean the contrivance of Nature, whereby the feveral minute
Feathers compofing the larger, are knit together lb firmly as to bear
the rtrong exertion of the bird in flying, without yielding a paflage
to the air.
The fame Author, in treating of hair, has thefe words, " The
" root of the hair was pretty fmooth, tapering inwards, almofl like
" a parfnip, nor could I find that it had any filaments, or any other
" veilels, fuch as the fibres of plants.
" The top when fplit (which is common in long hair) appeared
" like the end of a ftick, beaten till it be all^flittered, there being,
" not only two fplinters, but fometimes half a fcore and more.
" For the briltles of a hog, I found them to be, firft, a hard
" tranfparent horny fubflance, without the leaft appearance of pores
" or holes in it, and this I tried with the greatell care I was able,
" cutting many of them with a very Iharp razor, fo that they ap-
'- peared, even in the glafs, to have a pretty fmooth lurface, but
" fomewhat waved by the fawing to and fro of the razor, as is vifi-
" ble in the end of the prifmatical body A in the figure.* The fliape
" of the brifiles was very various, neither perfectly round, nor fliarp
•' edged, but prifmatical, with divers fides, and round angles as
" appears in the fame figure, -f-
* iMicrographia, p, 157. f Plate IX. _/% 17.
An extraordinary quantity of FiJJj on thefea coajl fiear Delft, noted by
the Author, ivith the reafons ajfigned by him for the fame,
XN the months of April and May 1716, tliere were brought to our
town of Delft, from the fea coafts at Schevling, Catwick, and Ter-
lieid, a great quantity of the fifh called haddocks, which, though
very frefh and good, were fold at a low price. The glut of this filh
was fo great, that though in general they are caught with hooks,
they were on this occafion, taken in nets.
Seeing this, I confidered, that there mufi: be ibme particular rea-
fon, why thefe fifli fliould at that time refort to our coafts in fuch
multitudes, and I was afterwards confirmed in that opinion, for in a
month or two afterwards, not one of thofe fifli was to be taken : and
tlie reafon which 1 alfigned to myfelf for the abundance I have men^-
tioned was, that at that time, there was a greater quantity of food
for them on the coafl: than ufual, whereby they had been tempted
tliither.
In order to inveftigate this matter, I opened the ftomachs of many
haddocks, and found them to be filled with a certain I'mall fpecies of
flirimps, called by our fifhermen meutjens, which are taken among,
the common flirimps, and are ufed for food by people living along the
Hi ore.
About a fortniglit afterwards, on examining the ftomachs of the
haddocks, I found I'omc of them quite empty, and others not more
( 284 )
than half filled with the before mentioned fniall fifli ; and fo much was
the glut then diminiflied, that few or no liaddocks were taken. Upon
enquiring the reafon of this diminution from a fifherman, he anfwered
only, that every fort of lilli liad its feafon, though I (hould rather
liave faid, in the words of fcripture, '-that where the food is, tliere
will the eagles be gathered together."
At the time there was this glut of haddocks, there was a great
quantity of cod fifli caught on our coall, the reafon of which I
took to be, that thefe cod flocked to our ihores in purfuit of the
liaddocks which are their food.
About the beginning of Ociobcr, in the fame year, tlierc were
taken on ovir coafts, great quantities of the common fhrimps, and
thole in better condition than they are generally found in the fum-
mer time. Hence I concluded, that tlie haddocks would again re-
fort to our coafts, and that the flirimjjs, to avoid them, would crowd
in greater quantities to the fliores and fliallows.
To fatisfy myfelf in this reri)e61:, and that I might learn what
j)articular kind of food is ufed by the haddock, I cauled the entrails
of a very large one to be brought to my houfe ; but, to my great
furprize, I found not only the ftomach, but the intellines adjoining-
it, to be entirely empty of food.
I enquired of a fifliwoman what might be the reafon of tliis, who
gave me the following anfwer: Our fifliermen (for flie lived at
Delftshaven) have a pond or ciftern, lined at tlie bottom and on
the fides with timber full of holes, fo that the water freely palles in
and out with the tide ; and the fifli being kept in tliis ciftern, can at
all times be brought to market alive and vigorous. But the hlher-
men fay, that when the haddocks are thrown into this ciftern, they
immediately empty their ftomachs of all the food they have fwal-
lowed.
Hereupon, I examined a little of the matter or fubftance contained
( 285 )
in the inteftines at a confiderable diflance from the ftomach, and
I found the fame to confifl of fragments of flirimps mixed with .
many particles of fand, rather larger than the fand found on the
fea fhore, and which particles of fand I concluded the haddock had
picked up with tlie fhrimps from the bottom of the fea, and had
fwallowed down both together. Among thefe grains of fand, 1 faw
many fliining particles, iome thoufands of which, laid together in an
heap, would not equal a large grain of fand : thefe were all of different
fliapes, but, in every one of them, the fides, angles and points,
were fo fmooth and glittering, as to be very little inferior in beauty
to the moft poliflied diamonds. At firlt, I fuppofed them to be no
other than common fait, but I found them to be much more hard
and folid than our lalt. After I had fteeped them a fliort time in
rain water, I could ftill diflinguifh fome of them, though much di-
miniflied in brightnefs ; others of them, feemed to be partly dif-
folved, and to be furrounded with fmaller particles : thefe latter, I
concluded to be, flill more minute falts, which, in diflblving, had
Separated from the larger ones, and afterwards concreted in cluflers.
In the month of November in the fame year, there was anotlier
great draught of haddocks on our coaft, whereupon I went to the
fifh marketto examine the inteftines, when newly taken out of the fifh :
I found mofi: of the flomachs to be empty of food, but fome re-
mains thereof in the inteflines ; and, as at the fame time, great
plenty of cod fifli were caught, I judged that the haddocks, avoid-
ing the purfuit of the cod, and thefe purfuing the haddocks, was the
reafon, that both were taken in fuch abundance.
Thofe perfons, who are very nice in their tafle, prefer the had-
docks brought to us from Maeflandfluys, to thofe that are brought
ftraight from the fea Ihore, though botli are taken near the lame
traft in the ocean.. Upon confidering with myfelf, what might be
the reafon of this difference, I could not aflign any more probable
( 286 )
one than this, that thofe haddocks which are brought flraight from
the fea fide, are, as foon as taken, thrown into bafkets, to the num-
ber of eight or ten in each bafket, and die, thus heaped together,
before they are expofed to fale : whereas, the fifliermen at Maef-
landfluys, keep their fifli for a time in thofe cifterns I have dc-
fcribed ; and the fifliermen of Delftfliaven, have alfo a kind of fifh
trunk or well in their boats for the like purpofe. Tlierefore, the
fifli which are thus kept alive witliout food for two or three days
after they are caught, are of a much better tafte.
The fame is experienced in river filh, efpecially trout, which,
when caught in the fummer time, are unpleafant to the palate,
tailing of the herbs on which they feed, but, if kept a few days in
flew ponds, cifterns, or other fit receptacles, are much improved in
flavour.
But to return to the fubje6l of the fifli market, I obferved a large
cod fifli, very much diftended with a quantity of food, namely,
haddocks, which it had devoured, when foine of the fmaller cod
lying near it, appeared empty. Hereupon, I enquired of an old
filhernian, whether thofe cod fifli, which were fo diftended, did not
differ in tafte from thofe, whofe ftomachs were empty ; to which he
anfwered, that thofe cod were to be preferred, whofe bellies were
compadl or clofe. This is a phrafe among fifliermen, applied to
thofe fifli whofe roes are not very large, and whofe ftomachs are
very little, or not at all diftended with food.
Of the Nutmeg ; the young plant in it difcovered ; the root of the Nut-
meg-tree examined and defcribed ; zvith fome hints from t/je Author
refpeSiing the befi method of preferring Nutmegs from being injured
by infers.
XlAVING, at many different times, employed myfelf in the exa-
mination of Nutmegs, in order, if poflible, to difcover the young plant
of the future tree (which, I was well affured they contained) but
always without fuccefs, I at length received, from one of the Di-
reftors of the Eafl India Company, refiding in our tovvn, a few
Nutmegs, and alfo a parcel of powder or dufty matter, which had
been found adhering to fome of the nuts *, to the intent, that I
might examine them, and fee whether this powder had not been
gnawed or bitten oif the nuts by mites.
With the greateft accuracy I was able, I examined this dufty
matter, and, with all my attention, I could not difcover in it any
mite either alive or dead, but in fome of the Nutmegs which had
been in part eaten away, I found feveral fmall maggots of different
kinds, and alfo a few flying infe6ls which I concluded had been bred
from maggots of the fame fpecies; but the bodies of all thefe
creatures were fo much fhrivelled, tliat I concluded they had been
long dead, and that, not being natives of thefe regions, they could
not endure the cold of our climate.
* This valuable fruit or fpice, which, in Englifh, is called by the fingle vvord Nutmet^, is
in Dutch denominated Noot Mufcaat, herein agreeing with the botanical Latin name Nux
mofchata, the Mufk-nut J it is alfo denominated Nux myriflica, the odoriferous or I'weet-
fmclling nut.
Nn
( c88 )
I next went to our Ea(t India Company's warelioufe, at the time
the olKcers enij)loyed to fort the fpices were biify in allotting the Nut-
megs according to tiieir qualities, and I brought home with mc, two
or three handfuls of the refufe tlirown away : any one upon view-
ing tliis with the naked eye, would cafily be led to conclude,
that it contained mites, but witli my utmofl attention, I could not
difcover any mites, much lefs their eggs, and only a few of the dead
infects I liave before mentioned. I alfo brought home ten or twelve
of the moR damaged Nutmegs, which felt very light in the hand, and
were much Ihrivelled : upon examining thefe carefully, I found that
moft part of the dull or powder, which upon a curfory view n^ight
be taken for mites, was nothing elfe than the dull: of the Nutmegs,
and the excrements of maggots which iuid ahnoit entirely fcooped
out the infides of tliofe nuts.
In the examination of thefe and other Nutmegs, it appeared to me,
thatthofe which had been gathered unripe, were the mofl liable to be
devoured by maggots, becaufe the oily matter in this nut, which per-
vades its fubflance in flreaks like the veins of marble, and covers the
out\\'ard bark in like manner, is contrary to the nature of thefe mag-
gots ; for when I cut open the nuts wherein they were, I found the
oily part every where uninjured, and on tlie contrary, all the whitilh
part of the nut con fumed, fo that thofe oily parts lay within the jiut,
exhibiting to me, as it were, a labyrinth of turnings and windings,
w'hereas, the unripe nuts, where the oily fubflance was not comi)letely
formed, were in the infides, quite confumed ; I alfo perceived the
external coat of the ripe nuts in fome places bored or eaten through,
but in my opinion, when the maggots reached the parts were the oil
was fully ripened, they defifted from farther biting, and only devoured
that part where the young plant is fituated, and which is the thickefl
part of the nut.
I was much furprifed, that I could not difcover any mites among
( 289 )
the Nutivegs, becaufe there is rarely any fubflance that can be ufed
for food, v.herethey are not to be found.
I determined tlierefore, to examine whether mites fed upon the
Nutmeg, and therefore I pLiced about a quarter of a nut, among
a parcel of mites, when I perceived that they fled from it.
Moreover, I took a glafs tube, fomewhat larger than a fwan's quill,
one end of wliich I flopped with a ccrk, and, after putting into the
glals fome hundreds of niites, I cut a fmall piece of Nutmeg of a fiza
that I could put it into the tube ; and I perceived that the mites next
tlie Nutrneg foon died. I then put another piece at the other ex-
ticmity of the tube where there were many live mites, which
alfo in a very (hort time died.
To fatisfy myfelf ftill farther, I took a glafs tube, tliirteen inches
long, and half an inch diameter ; one end of this I clofed by melting-
it, and put as many mites into it as I computed in bulk altogether to
be equal to half a cubic inch, and, according to the exa6tefl; compur
tation I could make, they were in number 150,000.
After thefe mites had been about a quarter of an hour in the tube,
they I'pread themfelves from the niafs in which tliey v/ere, when firft
put in, and difperfed all over the glafs; I then fplit a very found
and good Nutmeg into four parts, one of which parts I placed in the
open end of the glafs, fo that I might obferve by the microfcope,
what effeft it would have on the mites when they approached it.
Mofl of them I faw creeping towards the open end of the tube,
and when they came to within about a ftraw's breadth of that part
where the piece of nut touched the glafs by two of its points, many
of them returned back, though they miglit have paffed by tlie nut
without approaching nearer than the eighth part of an inch to the
main fubftance of it.
The retreat (fo to exprefs myfelf) of thefe multitudes of mites,
afforded me a very pleafant fpe6facle, for here it appeared, that the
exhalation or vapour proceeding from the piece of Nutmeg, was fo
N n 2
( 290 )
noxious and offenfive to them, that tliey drew "back from it fiifler
tlian tliey had ad\anccd towards it, in order to make their efcape out
of the glafs.
Some others of the miles having advanced fo far as to have got
fome hairs hreadth diflance be^^ond the Nutmeg, were prefently
arrefted in their courfe, and, lofing all motion, they expired.
Moreover, I obferved numbers of the mites creeping along the
glafs, near tliat part of the Nutmeg which was covered with
the rind, and they would have efcapcd, if I had not intercepted
them by placing another piece in tlie way, fo that they could not
get out without palfing tiie broken part of the nut, and hence it
appeared to me, that the vapour of the nut exhaled much more
-feebly next tiie rind, than from the internal newly broken part.
Hereby, not only the efcape of thefe mites was prevented, but all
tliat were near the nut died tiiere, and in the Ipace of eight and
forty hours, out of fo great a number of mites very few were left
alive.
To explain this experiment better, I caufed a drawing to be made of
the glafs tube I ufed on the occafioji, which is to be feen in Plate X,
fg. 1 , A B C D E F G H I . Heie, A I is the open end of the tube ; F,
the end \\'hich wasclofed, and in which the mites, when firft put into
the tube, lay in the greateft numbers. Between CD and FG, was
placed the firft quarter of the Nutmeg with the internal broken part
next the eye, where fome of the mites had crept on the other fide of
the glafs next the rind, and pafied by the nut, when as I mentioned
before, I placed the other piece of nut, with its broken fide the con-
trary way to the other, fo that the rind appears between A B and
H I next the eye, by which the mites were prevented from efcaping,
and all died within the glafs.
In refledling on the circumftance of thefe mites being thus killed,
I.judged that it was not by the vapour of the Nutmeg being hurtful
( 2C)1 )
to their bodies in general, fucli as the fkin, bones, Sec. but that it a6led
fo powerfully on the lungs of thofe creatures, as to prevent their ref-
piration. For, in like manner as noxious vapours do not, i'o far as
I know, in any manner injure our flcins, becaufe the moillure of our
bodies is continually expelled from the inward parts outwards,
through the Ikin to the furface ; and as no particles, either of foul air
or common water can be received into tlie body through the fkin,
for which reafon it is, that the flefhy parts of fiih or other animals,
living in water, however fait it be, do not partake of that faltnefs ;
fo mites, the fame'as larger animals, who are kept alive by refpi-
ration, die when that refpiration is obftrufted or prevented- And if
fo, we have here another inflance of the furprifing order and regu-
larity with which all things are created, fliewn in the wonderful for-
juation of the mite, which, thougli unknown to many perfons, and,
by reafon of its minutenefs, held of no account, does yet appear
to me, endowed witli greater perfeftion, and more curioufly formed
tJian many larger animals.
After the preceding obfervations, our Eafl India Fleet arrived,
whereupon, 1 became defirous to prociu'e foine of the Nutmegs
newly imported, and thofe of the befl and ripefi: ; in order, that if
poffible, I might fo far caufe them to vegetate, that I might be con-
vinced I faw the young plant in the nut, and miglit alfo be able to
take it out from thence. And one of our Ealt India Directors very
kindly gave me fornc of the largefl: Nutmegs ; among thefe I per-
ceived a few, which, though thoroughly ripe, were infefted with
maggots.
Two of thefe nuts I opened, and out of each I took a thick fliort
white maggot, about the fifteenth part of an inch in length, furnillied
with fix feet in the fore part of its body, and covered with a great
number of long and very flendcr hairs : from the fame nuts I alfo
took two or three pellicles or thin fl-iins of different fizes, which appa-
(292 )
rcntly had belonged to mai^gots of the fame fpecies, ^vhence I con-
cluded, that during tlieir gro'.vth, thefe maggots change tlieir flvins
in like manner as filk worms are obl'erved to do.
I alfo found in thefe nuts, two flying infects of dilierent kinds,
but tliey, as well as the maggots, notwithltanding all the care I could
take, foon died, whence I was more convinced that the maggots which
feed on the Nutmeg are not natives of thefe regions, and I do not
doubt, tiiat if the \\ arehoufes in Tnd'a, where Nutmegs are .kept,
were to be well fimiigated with fulphur, once a month, (for if this is
done only once, thole infeiis which are at that time alive may be
killed, but the minute maggots inclofed in the eggs will efcajie un-
hurt, and therefore tlie fumigation mufl be repeated) by this
operation the Nutmegs would, in a great meafure, be i^referved
from damage. And I alfo think, that it would be very proper to
fumigate tlie holds of the fliips with fulphur, by which means thefe
maggots, and thofe whofe nature it is to perforate and feed on tim-
ber ; alfo, tlie infects called cock roaches, tb.e millepedes, or tliou-
I'and legs, and even mice, which hide themfelves in the holds of fliips,
muft be all deftroyed.
1 endeavoured, tliree feveral times, to caufe the Nutmepf to-
vegetate, but I had not the good fortune to fucceed ; \\ iiich,
I think, was partly owing to the lime with which the nuts had
been fprinkled, and partly to their being fo much dried, that in
many places they v.'ere cracked in the infide. In this my fearcii, how-
ever, after dilleft ing many nuts, I at length, with great pleafurc, not
only difcovered the plant, but fucceeded in taking it out of the nut.
The outer part of the leaves of this plant was formed with many
indentings and points in the manner of vine leaves and the leaves
themfelves were as large as I ever found in the feed of aiiy
tree v.hatever. Upon viewing thefe leaves by the microfcope,
I could fee the veins or velTels, lying in as regular order, as are to-
be feen by the naked eye in the full grown leaf of any tree.
( 293 )
Fig. 1, KLAiN, reprefents this frnall plant taken cut of tiic
Nutmeg, as nearly as the Ihnner was able to draw it from tlie naked
eye; and though it fcenis to be compored of many leaves, yet, in
my judgment, there are but two ; but I could not examine that matter
very accurately, becaufe in the attempt, the plant was ofien broken.
The part in this hgure inarkcd N is th.at, from whence tlie flem and
root would grow.
Moreover, I placed a fmall p'ece of the outward part of this leaf
before a microfcope, and directed the limner to make a drawing of it
with all the veHels in it, as tliey appeared to him.
Fig. 3, OPORS, reprefents this piece of leaf; OP, is the part
which was broken off from the relt of tlie leaf, and O R is the
external edge of it.
In this fmall piece of leaf we not only fee, how the veffels or veins
are branchei out into fmaller ramifications, but in many places may
plainly befeen, the oily matter or fubllance, which is the fame in
nature and colour, as is to be feen in the nut itfelf. And fmce we
fee fo man}' branchings of the veins in fo fmall a piece of a leaf, who
can tell how many more ramifications there may be in it, entirely
cfcaping our fight }
During the time that I was employed in fearching for the plant
in the Nutmeg, I fell into converfation with a friend refpecling tlic
tree that bears this fruit, which tree, I was perfuaded, had fome
cavity in the middle of it ; this coming to the ears of a certain Pro-
fellbr, he fent me two pieces of the root of the Nutmeg tree.
Upon examining thofe pieces of root, both at the larger and
fmaller ends, I was grcatl}^ furprized to find, that this wood is of a
remarkably fpongy nature and very porous, though it has not any
cavity in it, different from the wood of other trees ; for, froin t])e
root, wc mull conchide, that the tree itfelf is of the like formation.
( 294. )
And in this root, I perceived feme wonderfully minute vefTels,
furrounding, as it in were, many places, the larger tubes of the wood,
and tln-ough which, as I fuppofe, the tree receives nourifliment in
its growth.
In order, as cxadlly as pofTiblc, to exhibit to view the wood, or
rather the root of the Nutmeg-tree, which bears liich a precious and
highly valued fruit, I havp given the figure of a circle, which wc
muft fuppofe to be a branch of the tree, or of its root, fawcd off
tranfverfely, as is to be fecn Vitfig. 4, ABCDEF. From the ccntcr
of this figure are drawn many very fmall lines, as appears between
CDF A, and thefe we arc to fuppofe are thofe veflels which fervc
for the increafeof the tree or root, and, by means of which, there
is every year a new fubflance formed about the tree, as I have often
heretofore mentioned.
Now, in order to inveftigate accurately, the true formation of this
wood, we muft not examine merely the extremity of it, which would
prefent an cbfcure obje6l to the eye, but we muft cut off a fmall
piece or particle of the wood, as from E to the circumference, after
we have, with a very thin and fharp knife, cut or pared the extre-
" mity as fmooth as poffible. In this manner I cut off a piece or par-
ticle of the wood, not fo large as is Ihewn 'dtfg. 5. This piece of
wood, placed before the mJcrofcope, and copied as exat^lly as the
limner was able to reprefent it in his drawing, is fliewn at /Ig. 6,
ABCDEFGH, and in it are to be fcen, many of the veilels or
tubes of which the wood confifts, fome of the larger ones of wliich,
I have exhibited at I, I, I.
Amonsf thefe larger tubes of the wood are to be feen a great
number of fmaller ones, and niany of thefe fmaller tubes are again
furrounded by other exceflively minute veflels, through which latter
ved'els, for the moft part, the nourifliment is conveyed Upwards in
the tree, as I fuppofe.
( ^9rj )
But, as thefe fmallcr vefTels, which are plainly to be fcen by the
microlcope, cannot, by reafon of their minutenefs be well expredbd
in a drawing, unlefs ftill more enlarged, I ufed a niicrofcope of greater
inagnifying power, and cauied a fmall portion of the wood which
in Jig. 6, is iituated between the two larger veflels, K and L, to be
drawn fomewhat larger than it appeared through the inici'ofcope be-
fore w'hich it was placed, and this is fliewn mjig. 7. ABCD.
This piece of wood was fo cut, that all the horizontal veflels were
exactly divided, and I could plainly perceive them, whether I
viewed tlie obje<5l up\^•ards or downwards ; and I further faw% that
where the horizontal veflels lay, there the larger tubes of the wood
were fituated, as appears in this figure at AB, and DC, which is
where the horizontal velfels were fituated.
h^Jig. 6, are alio fliewn, the horizontal veflels which take their
courfe among the perpendicular veflels or tubes of the wood, but, as
all the afcending veflels or tubes are cut tranfverfely, fo that their
cavities become confpicuous, on the contrary, the horizontal
v-eflels, by this manner of cutting, preferve their fliape as near as
may be. Jn this figure there appear more of thefe lafl veflels about
the parts marked A and B, than about G, or between G and F ; the
rc'afon of wliich is, that in fplitting the wood, the knife did not pafs
in lb firaight a direction along thole veflels as I wiflied : for the
fame reafon thefe horizontal veflels appear in greater numbers at E,
or between E and F, tlian about C.
hi thefe horizontal veflels may Ijc feen a red and yellowifli fub-
(lance, fmiilar to the oily matter in tlie Nutmeg, and the young
plant it contains, fo that the horizontal veflels arc of a reddifh colour.
Fartlier, I determined to cut thefe horizontal veflels, each of which
can be diftinctly feen, and which generally lie three, or at the moft,
four together in rows, in an oblique manner, fo as to exhibit their
cavities to view. A fmall particle of tlie wood reprefented &tfig. 4,
Oo
( 2C,6 )
ABCD F, fplit lengtliwife, at the part marked DF, I placed before-
a microfcope, and this very tliin particle, fo fplit off, is fliewii at
;^-. 8, PORS, in which appenr eight dilUnct places, where the hori-
zontal veilels are cut in this oblique numncr, as may be feen by the
cavities in many of them, a part of which is fliewn at O.
The perpendicular afcending vellels, fg. 8, P S, or Q R, are thofe-
fmall vefTels, which mfg. 6, between K and L are fliewn cut obliquely.
Moreover, I fpht this branch of wood in the middle, as the line
ABC m^g. 4 denotes, and from the piece fo fplit, I cut a fmall par-
ticle, dividing the horizontal vefl'els longitudinally. This particle of
wood is reprefented ntfig. g, T VW X Y Z A B, w here T V, and Y Z,
are the afcending veHels, and the horizontal vefTels which crofs them,
are fliewn at \VX and AB : and in, and among thefe horizontal veflels
we faw various minute globules, which the limner, as nearly as he
was able, imitated in the drawing.
In my obfervations on this wood, I faw four I'everal kinds of
woody tubes, befides other fmaller ones, which, by reafon of their
jninutenefs, as I judged, could not be diiiindlly feen , but thofe w hich
could be dihinguifiied I caufed to be drawn.
Fig. 10, CD, reprefents a tube of the wood partly compofed of
annular parts, like a wire wound round a pin ; and, next this a tube
formed in a ditYerent manner, feeming to confift of a pellucid mem-
brane, covered with many fmall dots or fpecks, which in I'everal places
were contiguous to each other; this tube is reprelented m ^g- lo,
atEE.
Fig. Ti, G H, reprefents a third tube of the wood, covered with
fmaller fpecks or dots, but, what is more remarkable, it contains
in this fmall fpace five joints, very much like thofe of v>iiich Itraw
is compoied : two of thefe joints are reprefented at G and H.
I endeavoured alfo, if pofllble, to difcover the formation of the
larger tubes, ihcwnin fg. 6, at I, I, K,L, and while 1 was thus
( 2p7 )
employed, it a])peared to me, tliat the tranfparent membrane con-
ftitutiug the tube, was compofed of veirds taking their courle round
about the tube.
To make proof of this, I tore fome of thefe tubes of the wood
afunder longitudinally, when I perceived, that where torn, they were
very much indented or jagged, whence I concluded, that however
tranfparent they might appear to me, they were yet compofed of a
"■reat number of veifels Ivinsr in a circular direction.
F/l'. 12, 1 K, reprefents apart of one of thole larger tubes fo torn and
jagged, which is very clofely united to the adjoining fmall veflel
at L M in the fame figure, and from which, as I think, this larger
tube received nourifliment in its growth, and the rather becaufe,
though the membrane or coat of this tube appeared tranfparent, yet.'
it plainly appeared, that the membrane was compofed of minute
velTels, w^iich appeared to derive their origin from that fmall veffel.
I then proceeded to examine thefe larger tubes of the wood, with
all the accuracy I was able, and I was well afllired, that I faw the
membrane compofing them to be made of vefTels like ftreaks croffing
each otlier at right angles ; a particle of this membrane is fliewa
m/g. 12, at LNOI, where the vedels or ftreaks from I to N and
from L to O mutually crofs each otlier, by which means tliis thin
fubftance is ftrengthened ; and who can tell how many, and what
various parts fuch a tube of the wood may contain ?
I think I have formerly faid, refpe6ling the veins in the
leaves of trees, tliat they are of a fpiral t\\ ifted form, like that re-
prefented in /^. lo at CD ; and alfo, that the firing by which many
nuts (as the filberd, almond, &c. ) have nourifliment conveyed to
them through the hard fnclls, confifts of many veflels of tlie like
kind, and upon recolle6i:ing this I determined, as far as I was able, to
-dideft the young plant I had taken out of the Nutmeg, to fee whe-
ther the veHels reprefented mfg. lo, at CD and which are in great
aiumbers in the wood, could alfo be found in, the young plant.
Go 3
( 29S )
For this purpofe, I firft examined the leaf of tlie young plant, in
that part where it was fo thick as to be opakc, and immediately I faw
in it three dirtin6l veilels of the like fpiral or twifted form, as I have
before mentioned to have feen in tlie root. This ei^.quiry I profe-
cuted as far as the extremity of the leaf, where I faw a fmall vellel
of the like kind, and fo diftinclly, that I could count every fingle
fold or fpiral turning in it.
Since it now appears plain to us, that provident Nature forms all
the veflels of this tree in fo perfect a manner, that the fmall ones in a
young plant in the feed, are as plainly to be feen as thofe in the
wood at full growth, which we may jullly conclude is the cafe in all.
feeds, however minute ; we are not to wonder that the fmalleft of any
animal which we view by the microlcope, is as completely provided
with all its parts as when it is grown larger. In a word, the fartlier
we endeavour to dive into the hidden works of Nature, the more wo
ought to be convinced, that we never can arrive at her farthefl receffes,
though many perfons, when making ufe of a good microlcope^
weakly fuppofe, that nothing is out of the reach of their obfcrvation..
On damaged Mace, commonly called xvhite Mace ; the cauje from
tahence this defeat arifes, Jhezvn to be oji infedl ivhich feeds on the
internal parts of the Mace, with a particular defcription of that'
infe£i j and fome farther account of the Nutmeg.
Upon hearing formerly, mention made of that fort of Mace
which is denominated white Mace, I merely thought, that it was not
fo good either in flavour or virtue as the reddifli-coloured Mace, and
the rather, as I long ago heard that a certain phyhcian had the art to
eive the white Mace the fame colour as the beft ; but havincr been
fmce informed that this white Mace had fo little virtue, that it was
Ibrted from the reft and burnt, and hearing that its inferiority was
fuppofed to proceed from fome defe6l or want of nourilhment in the
growth of the plant, I had a great defire to examine the nature of
this white Mace.
On converfing upon this fubje(51: w ith one of the Directors of our
Eaft India Company, he informed me of the time wlicn the officers
at the Company's warehoufe, were employed to fort out the
white Mace, and gave me permifhon to go to the warehoufe
and fatisfy my curiofity in this refpecL I accordingly attended
at the warehoufe, and perceived, not without furprize, that the
white Mace was compofed of nothing but thin membranes or fkins,
and I alfo obferved a kind of webs, which I concluded had been fputr
by fome infedl, wliich webs were fixed to ibme of the Mace, not
only tlie found, but alfo the damaged. I brought home with me
eight or ten of thefe webs, and found them to be covered in part
( 300 )
with certain oblong black particles, whicli I concluded to "be the ex-
crements of the maggots, by which thole webs had been fpun : in
iuveral of thefe webs, I alfo faw certain particles which feemed to
be the fragments of aurelias, from whicli fome I'pecies of flying in-
le(5l had proceeded, and, as in one of thefe \\ebs I perceived feveral
minute feathers, very much like thofe found on the wings of motiis,
1 further concluded, that the flying infe61:s which proceeded from thefe
webs mull bear fome refemblance to the moths in this country.
In order to fatisfy myfelf further, I went the next day to the Com-
pany's warehoufe, and fpent a wliolc liour with fome of .the officers
m fearch of thefe webs, and at the fame time, tlie ofliccrs gave me a
leaf or piece of Mace very much flirivelled, in wliich was the ap-
perance of a web, and on opening the leaf, I found in it a v^hite flying
infe6l, (which was not only dead, but had loft fome of its legs,) in
fhape and fize not unlike thofe white moths tliat are found in grana-
ries, and from Avhofe eggs proceeds the maggot called the wolf,*
though I judged this infecl to be of a different fpecies. Upon my
return home, I examined all the webs I had found, and in feveral of
them, diicovered the Ikins or cafes of aurelias, from which flying
infedls had proceeded, and in two of th.em, the infefis themfelves ;
I alfo found one ])erfe5: cryfalis, and in it the infeft dead ; and upon
attentively examining this cryfalis, I plainly perceived that it was ex-
actly of the fame fhape and nature with all the other fkins of aurelias
which I had found. I caufed a drawing to be made of this aurelia
or cryfalis of the fame fize it appeared to the naked eye; this is
fliev»-n at figure 13, AB, in which the refemblance is taken as accu-
rately as the limner could imitate it in Iris drawing.
Fig. 14, CDreprefents the flying infe(5l which proceeded from
one of thefe aurelias , the wings of which, wOuld I believe, Iiave
appeared longer than here reprefented, had not the animal while
* The defcriptioii of this ir.fciSt is to bu ften at page 25.
C 301 )
llruggling to get out from amongft the Mace wliere it was enclofed,
broken oiY part of them, in which flriiggle alfo, I fancy it had been
killed.
After this, I appHed myfelf to examine the white Mace, as it is
called, a parcel of which I liad brought home with me ; and I im-
mediately perceived that all the matter or fubflance which had been
enclofed between the membranes compofing the outward furface of
the Mace, \^"as confumed or eaten away. 7'his fubftance, which
for the moft part, confills of oily globules-; in which the whole
virtue of the Mace confifts, being i'o Ilripped from thofe mem-
branes (of which membranes,, the leaves of all plants, however fmall
they be, are compofed, and whereby the internal moillure of the
leaf is kept from evaporation) nothing remains but the thin mem-
branes themfelves, confiding of wonderfully minute veflels, lying
lengthwife in the leaf, which altogether exhibit a white appearance :
hence thefe leaves are called white leaves, or white flowers of Mace,
whereas, in facl they are nothing but the very thin membranes of
tliofe leaves.
I found, on the infide of thefe membranes, various oblong particles
pointed at the ends, and fome of tliem tranfparent; thefe I concluded
to be. the excrements of the maggots-I have mentioned, and to have
been voided by them at different periods of tlieir growtli, becaufe,
though of different fizes, thel'e particles were all of the fame fhape.
Farther, I obferved fome of the broader leaves of Mace to be fo eaten
av/ay, that only one of the membranes remained, and having in
vain fought among them for any animalcule, I threw them all away.
After this, I procured a frefn fupply of the white leaves of Mace,
not doubting that I fiiould find fome dead animals among them.
At length, after a long fearch, I found a fmall white particle, not
larger than a grain of fand, which, examining by the microfcope, I
found to be an animalcule, the hind part of wliofe body wastranf-
( 302 )
parent and oblong, but the fore part was covered willi fome ex-
traneous matter, which endeavoui-ing to wipe away, I broke it off
from the hind part.
I was, howe\ er, hereby induced to make a further fearch, not doubt-
ing, that I (hould find fome of thefe infe(^l:s of a large fize, but I
could not difcover any of them among the leaves whofe membranes
were entirely itripped of their contents ; whence I concluded, that
the maggots, when grown large, had either quitted the leaves or un-
dergone a change in their form, whereupon I fat about examining
thofe white leaves which lay next the others that were found, as alio
thofe leaves which were in great part, but not wholly, confumed ;
fix or feven of whic'i I had brought with me ; and among thele, I
found a few animalcules of the fame fliape with the one I laft men-
tioned ; thefe were not only larger than the former, but their bodies
were of a reddifli colour, and I judged that this colour proceeded
from their feeding on the oily matter, of which the Mace, for the
greatefl part confifts, and that the former tranfparent animal had died
before it had fed on that coloured fubflance.
At fig. 15, is fhewn one of thefe maggots, of the fame fize as it
appeared to the naked eye ; this was one of tlie largcfl that I liad
met with in my fearch.
The difcovery of thefe maggots very much excited my admiration,
becaufe I had never feen any thing like them in the Nutmeg, and
the more, becaufe thefe maggots feed and fubfifl: on the oil in the
Mace, of which oil the Nutmegs are alio in part compofed. But the
reafon why thofe animalcules, which feek their food in the Nutmeg
are not found in the Mace, is, in my opinion this, that thofe which
devour the Nutmeg avoid the oily matter it contains and only feed on
thofe parts of the nut where there is little or none of that oil.
Having thus difcovcred the maggots (defcribcd in fig. 16,) which
feed on that thin matter or fubflance found within the membranes of
( 303 )
the Mace, and which afterwards quit the Mace, leaving the mem-
branes themfelves unhurt, except in that part wliere they firft gained
admittance ; I caufed a drawing to be made of fome of thefe Mace
leaves, a part of which is of that fort called white Mace,
Fig. 16, A B K C D E, exhibits part of a leaf of Mace, and in this
figure, between EFG and H, may be feen the llripes of the leaf,
which are engraved with very light touches, fo as to give the appear-
ance of white ; thefe are tlie parts called white Mace, and from them
the oily fubltance is all confumcd, leaving only the bare membranes.
Now, if this whiteness had been caufed by the want of nourilhment
in the plant, then the extremities of the leaves at C or D, woidd have
been white alfo, whereas, on the contrary, they were of the proper
colour, and of a good flavour, by reafon that the maggots had
not eaten away the oil from within tlie membranes farther than
where the leaves appeared wliite.
Lower down, in the figure, between G and H, may be feen a
fmall hole made in the membrane of the leaf, which I conclude, was
bitten by the maggot, to open for itfelf a paflage into the leaf, and
the rather, becaufe the thin membranes in tliis part of the leaf were
entirely unhurt, nor did there appear any perforation in them, ex-
cept in the before mentioned place towards A B. And, if we confider
the narrownefs of the cavity in tliefe white leaves, where the oil is
eaten away, we inay conclude, that it muft have been an exceeding
minute creature which could turn itfelf about in fo fmall a fpace, and
then procure its fubfiftence ; and, between the membranes in this
part of the leaf, I found nothing, except the excrements of the
maggot.
When I was endeavouring, fome time fmce, to difcoverthe young
plant in the Nutmeg, I alfo tried to find out, in what manner the
nut, while inclofed in its fliell, received iiourifhmcnt from tlie tree ;
and for that purpofe, I took a Nutmeg which was preferved in fugar,
Pp
( 304 )
and difre6led it, but, as the fyrup had penetrated into the infide of
the nut and was there candied, my fearch was at that time fruitiefs ;
however, during my prefent inquiry, the forters of fpices prefenled
me with lix or eight Nutmegs, wliich they had found among the
Mace, which, with their original hufks, and the Mace inclofmg
them, altogether ibmewhat bigger than large hazel nuts ; and alfo
two of the lame, Ibmewhat larger.
Upon examining thcfe nuts attentively, I perceived, that the fkin
which covers tlie hard bark or fliell of the Nutmeg, was perforated
in Ibme places among the Mace, though the Mace leaves themfelves
were unhurt ; hence I judged, that this perforation was the work of
thofe maggots, or animalcules which I have in another place men-
tioned, as feeding on thofe parts of the Nutmeg wherein there is
none of the oily matter compofing the Mace, on which oil they can-
not fubfift.
I viewed the Mace which inclofed thefe Nutmegs by the micro-
fcope, and found it to be covered with many dried bodies of
mites, but in all my fearch, I could not difcover any Hving mite,
whence I concluded, that the packages inclofmg thefe Nutmegs, iiad
been flowed in a part of the fliip near the bread-room, and, upon
enquiry, I found that this had actually been the cafe ; fo that I
doubt not, thefe mites, which multiply in vafl: numbers among the
bread, had been killed, when the packages of Nutmegs and Mace
were flow ed there : and this confirms what I have, in another place
mentioned, that the vapour of Nutmegs is mortal to thofe creatures.
Farther, upon examining thefe Nutmegs, and the leaves of Mace
inclofmg them, I obferved in feveral of them, that, at the part where
they receive their nourifliment from the tree, they were perforated
with a fmall round hole, penetrating into the nut itfelf, the Mace
for the mod part appearing untouched ; and this was done where
the bark of the nut was the fofteft : in one of thefe holes I found a
( SOJ )
dead flying infedl, of the fame fpecies witli tliore, many of which
1 have mentioned to liave found in the Nutmeg. Upon breaking
open one of thefe nuts, I faw, tliat all the internal vvhitifli fub-
flance of it, where there had been little of the oil, was eaten away,
and nothing left in the cavity except the excrements of the maggot,
and the web it had fpun while in that place ; but, as I did not find any
(kin or remnant of an aurelia, I judged that the maggot, not finding
a fufficient quantity of iull:enance in this nut, had quitted it before it
arrived at its full growth. On this occafion, I could not but admire
theinftinft which teaches thefe infefts to perforate the hard Ihell of
the Nutmegs, and for that purpofe, to find out that part in it which
is fofter than the reft ; for tliis I found to be the cafe not merely in
one or two inftances, but in as many as ten Nutmegs, I obferved the
fame.
Fig. 17, L MN, reprefents the Nutmeg inclofed in its fhell, and
covered with the leaves of Mace, but which coverings are, in India
Itripped off while frefli and green. All thefe receive their growth
and increafe through the part between L and M, which is the place
where the nut adjoins to the tree ; and I at firft thought, that the
Nutmeg was nourilhed from its fliell or bark, as I had obferved w^as
the cafe with the walnut ; but upon a more careful inveftigation,
and after cutting open the fliell with a fine faw, I found, that I had
been miftaken herein, for I could not difcover any thing at the part
marked L M, which had the appearance of having tranfmitted
nourifliment to the fruit. I foon, however, perceived two places
adjoining to each other, one, as I concluded, for the nouriflnnent of
the bark, and the other of the nut itfelf ; and, on further fearching,
I law, that the veflels deftined for this purpofe, did not immediately
enter the nut at that point, as I had obferved in filberts, almonds,
and other feeds, but that the veflels in this nut take a courfe from
M 'n-\fg. 17 to the point of the nut at N, and there pals through the
Pp2
( 306 )
fiiell, and by this means, the nut receives its nourifhment ; for it is
not united to its Ihell in any other place.
To exhibit this to the eye, I caufed a drawing to be made of the
bark or fliell containing the Nutmeg, after the leaves of Mace had
been ftrij^ped off", and having alfo firfl: loofened from it the firing
through the veflels in which nourilhment is conveyed, leavingonly the
firing affixed to the part where it enters through the bark, to Ihew
more plainly the place where the nut receives its nourifliment.
Fig. 18, O PQ, reprefents the bark or Ihell wherein the Nutmeg
is inclofed ; Q R, is the firing, confifling of multitudes of veflels which
convey nourifhment to the nut; O and O exhibit the furrow or
creafe wherein the firing lay before it was pulled out. This firing I
cut into very thin flices, fome of which I placed before the micro-
fcope, that I might the better difcern the great number of veffels in
them, of which I caufed a drawing to be made, as nearly as they
could be diflinguilhed and reprefented. This is fhewn in /^. ig,
A B C D E, being one of the flices I have mentioned, cut obliquely,
and magnified.
Now, if we contemplate the incredible number of veflels in fo
fmall a firing, (for that which infig.iS is fliewn at Q R, is, in
reality twice the fize of the real firing, becaufe I did not flrip it of
the fkin which covered it, lefl I fhould injure the veflels it contained)
befides thofe which the fight cannot reach, we mufl conclude, and
be afl'ured, that there is not a \eiVe\ m a full grown Nutmeg tree, for
whatever ufe it may be deftined, but there is a fimilar one in this
firing ; otherwife it could not communicate to the young plant
in the Nutmeg, all the veflels requifite for the formation of the future
tree and fruit.
In a word, the inconceivable perfedlions whiqji are contained in
thefe firings of plants, and confequently in every feed, are to us in-
comprehenfible, and, ftill more, infcrutable.
( 307 )
Moreover, I have given a drawing of the bark or fhell of the
Nutmeg, when broken hi two, having firft ftiick a pin into the place
through which the firing, wliich I have been defcribing paiies, in
order more plainly to fhew the nature of it. Tliis is reprei'ented at
fig. 20, ST V, in which figure, W X is the pin, marking the place
through which the firing palled, and at Y is a kind of protuberance
on the infide of the fhell ; in the nut itfelf is a cavity correfponding
with it, and above this cavity, is the place where the firing is united
to the nut ; but the firings are almofl always broken from the Nut-
megs before they arrive in Europe, becaufe the nuts in drying, or by
the evaporation of their moiflure, become fmaller, whereas the hard
fiiell dries and fhrinks little or nothing, fo that the nut getting loofe
within, does, by its weight break off the firing, and, when fliaken in
the fliell may be heard to rattle.
At fig. 21, F G H, is a drawing of a piece of the fhell at that end
next the tree, and at K is the round hole I have mentioned, in one
of which holes, I found a flying infe61; : in this figure alfo, that part
of tile firing conveying the nourifhment to the nut, and which here,
is joined to the tree, is fhewn at IKL : this fhell being removed, I
found that the animal had penetrated into the nut as I have before
obferved.
Fig. 22, MNO, reprefents the nut itfelf, in which the above men-
tioned fmall hole, is fliew-n between P and O : at this place, the
young plant is fituated in the nut, and here alfo, as far as I have ever
obferved, the infecls penetrate the nuts becaufe it is the foftefi: part
of the fruit, and contains the Icafl of the oil.
Since we now fee, tliat thefe creatures, not only when maggots,
but alfo when changed into flying infe61s, feed on thofe parts of the
nut where the oil leafi: abounds, we may readily conclude that, how-
ever minute, they are very pernicious to Nutmegs. In the flate of
flying infc61s, however, they are not, in my opinion, fo hurtful on
( 30^ )
account of their feeding on the Nutmeg, as by laying their eggs, the
maggots proceeding from wliich, mufi; be exceedingly pernicious,
becauft tlicy acquire their wliole growth within the nut.
I am perfuadcd, that if the timber and wood inwarehoufes was
painted with the common red paint ufed in tliis country, the fpices
might be preferved from many noxious infecfts, becaufe the particles
of that paint, though ground very fine, are of fo hard a nature, tliat
no fmall infect can penetrate them. And if the wood is obferved
to be perforated >vith many worm-holes, the paiiuing fhould be
repeated until all thofe holes arc (lopped up with it.
It may be faid indeed, that Nutmegs and Mace are kept but a fliort
time in the warehoufes, and therefore not liable to be much injured ;
but in that fliort time, and while expofed to dry, they may be in-
fe6led by thefe flying infedls laying their eggs among tliem ; and it
is well known, that many of thefe creatures lay many eggs in a very
little time. Indeed, if Nutmegs and Mace are kept in large heaps in
the warehoufes, I believe that only the furface of them might be ex-
pofed to injury, becaui'e the infedls cannot penetrate far into the
heaps to lay their eggs, and therefore the middle of thefe heaps may
be uninjured.
But thefe matters are all conje61:ure, and, as it were, riddles to us
at this dirtance, refpedting which, thofe who are employed upon the
fpot, in colle6ting or drying the I'pices, could give much better in-
formation, if they were perfons of intelligence and obfervation.
To return to the infects which I found among the Mace ; I was
doubtful how to purfue my enquiry refpe6ting the generation of thele
creatures, and the rather, becaufe thofe which I found, were not
only dead, but their bodies very much dried, for, had they been
living, I doubt not, that I fliould eafily have difcovered the manner
in which their fpecies is propagated.
At length, upon confidering the Ihape and make of thefe mag-
( 309 )
gots, and, having feen by the micro fcope, that their bodies are
formed with creafes or rings, it occurred to me, that they were of
that Ibrt which do not bring forth young ones while in that ftate,
but, hke catterpiilars, feveral kinds of maggots, and alfo fleas,
change into aurelias, and thefe again into flying or creeping infedls,
and in that ftate couple and lay eggs.
Now, as 1 had found thel'e maggots among the Ikins of the Mace,
I concluded, that when their change approaches, it is in their nature
to abandon the leaves : and, as in my former learcli i had found a
cry falls, which I concluded had been changed from one of thefe
maggots, inclofed in its fliell or covering, I went a third time to the
India Company's warehoufe, and caufed a confiderable quantity of the
white Mace to be put into a fieve and fifted, in expe61:ation, that
among the finer parts, which palled through the fieve, I fliould find
feveral infe^fs that had gone through their change.
By this means, I obtained two handfuls of fmall matter or duft,
mixed with many minute particles of Mace, but I perceived, that
the greater part confifted of the excrements of infe6ls ; I alfo
took a handful of duft, fifted from a parcel of Mace, before the
officers had forted the damaged from the found : on my return,
I carefully examined the whole, and found in it, at leaft one hundred
dead animals, which I concluded had been produced from the be-
fore mentioned maggots, I alfo found two flying infedfs of the fame
fort with thofe which I had obferved in the Nutmeg ; likewife the
fkins of two aurelias, and one of thofe creatures called a weevil, but
which, as well as the reft, was dead. Such of thefe animals as had
been produced by tranfmutation, were all of the like make, and al-
moft of the fame fize as the full grown miaggots, and 1 judged, that
if they had not proceeded from thofe maggots, they would have
been of different fizes.
Some of thefe maggots, I placed before different microfcopes.
( 310 )
rliat I might caufe a drawing to be made of fuch one of tlicm as was
the mofl perfe6l, becaufe all that I found were not only dead, but fo
dried, that the leaft touch would break their bodies, or at leafl their
feet.
I have already given ^t fg. ^^, a drawing of one of tliefe maggots,
of the natural fize; Fig. 23, EFGHIKLMNO, rcjM'cfents the lame
maggot as feen through the microfcope : the body of tiiis creature
is formed with many joints or riiigs, alfo with fix fmall feet, fur-
niihed with cm^ious nails, the extremities of which nails arc indented
or notched, as fhewn at G and N.
In the lower part of the body of this animal, as well on the belly
as on the back, there appears an uncommon number of blood veilels,
which, on each fide of the body at H I and ML are the thickeft and
largelt, and leem to come from the inner part of the body : thefe
blood vefTels are divided into various exceedingly minute branches,
leveral of which, proceeding from H to M, and from M to H there
meet, and arc again united, which not only appears in the branches
about H and M, but alfo through the whole body, though the limner
could not reprefent them all.
In the head of this creature, fo many organs appeared, that they
could not all be copied in the drawing.
At O and F are reprefented, two prettily fliaped horns, made with
joints, and covered with hairs : at E is the mouth, or rather two
teeth, fomething like pincers, with which the maggot, as I judge
bites into the leaves of the Nutmeg on which it feeds, and fcrapes
off the fubftance they contain ; within the fkin at P P are two other
organs with which the head of this maggot is furniflied.
I know very well, that thefe fmall animals are called bloodlefs, a
name given to them by thofe, who, I fuppofe could not difcover
either the blood or the blood vedcls, but this miftake I attribute only
to their want of better information.
( 311 )
Now, as all caterpillars, maggots, and other fmall aiiimals when
changed into flying infe6ts do dill preferve the fame I'ort of creafes,
rings, or divifions, which they originally had, fo I perceived in the
flying animal, produced from thefe maggots, the fame kind of rings
or divifions, but thefe did not become confpicuous till the two flielLs,
or cafes which covered the hind part of the body were removed :
under thefe cafes lie two exceeding i'mall wings folded together, and
by reafon of their being longer than the body, doubled up : fo that it
feems probable to me, that thefe creatures are formed in the fame
manner as infefts of the beetle kind, with regard to their wings, and
the cafes that cover them.
If we refle6t on the nature of thofe flying animals, whofe wings
are thus folded up and covered with fliields or cafes, and who are
deftined to feek their food in hard fubftances, fuch as wood, nuts,
and the like, or who are hatched in tlie earth, we Ihall fee the ne-
cefllty of their wings being formed in that manner, for if the wings
were not longer than the hind parts of their bodies, they would be
too fmall for flight, and if not defended by the cafes or fhields, they
would be liable, when the animals are creeping into holes either in
the earth or in the hard fubftances on which they feed, to be lb
broken or injured, as to be unfit for the purpofe of bearing them
through tlie air.
Tiiefe animals, even after they are converted into flying infeils,
do, in my opinion, take food, contrary to what is obferved in the
moths or butterflies produced from filk- worms and caterpillars, for
I obferved, that fome of thefe were of a bright and others of a dark
red, the former of whicJi, I fuppofe, had not been long changed,
and therefore had not taken fo much food as the latter.
I liave often thought, that perhaps, tiieie kiiids of animals may
feed upon wood, but, that when tliey get among Mace, which is of
( 3^2 )
a much fofter nature, tlicy may tlicn inultiply much fafter than
thole which breed in wood, and efpetially in the harder forts.
I placed one of thefc creatures, changed from tiie maggot into a
flying infe61:, before the microfcope, and having removed the Ihields
or cafes of its wings a httle afide, in hke manner as if the animal
was livin.g and about to take its flight, I beheld fo wonderful a piece
of workmanfliip, wrought with fuch curious art, that I determined
to have a drawing made of it, tliough it was impofTible to delineate
all the wonders that were difplayed in this minute animal.
Fig. 24, ABC DEFGHIKL, exhibits this flying animal, which
appeared longer than the maggot from which it was produced, the
reafon of which I take to be, that the bodies of thefe maggots being
very foft, they contrad when their moifture evaporates, M'hereas
when changed into flying animals their bodies are hard on the outfide,
and therefore cannot contrail.
LM, and BN, are the two horns made with many joints and
covered with hairs.
L, B, are the eyes compofed of various optical organs, thougli
but few in comparifon of thofe which are found in tiie eyes of
flics.
This creature has fix feet, each furniflied with two curioufly
made little claws ; the legs are made with various joints at the
extremities, and are covered with hairs, or rather with pointed par-
ticles like thofe on brambles : two of thefe legs with their claws, are
fliewn at C O and D P.
At DI and KI are pi6lured the two fliields, or cafes, with which
the animal, when not in the a6t of flying, can cover the hind part of
its body, fo that I conclude, no particles of the wood, or of the Mace,
nor any drops of water which may accidentally fall on its body, can
injure tlie wings.
Upon attentively contemplating thefe fliields or cafes, I was
( 313 )
afloniflied at the wonderful and elaborate workmaiifhip exhibited in
this creature, v.hich appears fo minute to the naked eye, but does,
I think, in perfection, far exceed the larger animals we daily
behold.
If we advert to the hind part of the body, formed with joints
jndented in the fame manner as in the maggot, from which, by
tranfjTiutation it was produced, and obferve the multitudes of veins,
fcattered over it, we mufi: more and more be confounded at fuch
great perfe61:ion in fo minute a creature.
In like manner in the wings, we fee many vefTels and finews,
which finews fcr\"e to expand and firejigthen them ; likewife many
pointed particles or hairs, with which the membranes of the wings
are covered : it is alfo worthy of obfervation, how the wings are
folded and doubled up, both in length and breadth (which is fliewn
between G and H, as nearly as the limner could imitate it) in order
that they may be entirely covered by the cafes ; befides which, this
animal is provided with another exceedingly minute wing on each
fide. Let us alfo confider, with what inconceivably minute finews
or mufcles thefe wings muft be provided, in order that the ani-
mal, when it prepares for fiight, may unfold them both in length and
breadth ; and how the joints and finews mufi: be contrived, fo to
ftrengthen the wings when unfolded, that by their fwift vibrations,
the animal may fliape its courfe through the air.
In order, more clearly, to give an idea of the foldings in tliefe
wings, I took one of them from under its cafe, and placed it, together
with the finew or mufcle which adiiered to it, before a microfcone,
diredting the limner to make a drawing of it, and alfo of the finew,
whereby the wing is unfolded and put in motion.
F/ij, 25, OSVWXY, reprefents this wing according to its
pofition when covered by the cafe or flicll ; V, is the broadeft part of
the wing, and this part lay either under or above the correfponding
Qq2
( Si-i )
^ving. OR is the mufcular part, by means of which, not only the
wing is put in motion, but doubtlefs many lefler mufcles are derived
from this, by means of which, that part of tiie wing at WXY is
extended in length, and the part at Y O expanded in breadth: at
S T is the minute wing; I mentioned above.
When we duly confider this mod perfe6l workmanlhij) of the
Divine Artift, we mufl confefs, that thofe things which we difcover
by our microfcopes and induftry, are but as the fhadow of thofe
which hitherto remain concealed from us, not only in fuch fmall
animals as this now under confideration, but alfo in larger animals,
and in plants.
It is to be hoped then, that the enquirers into Nature's works, by
fearching deeper and deeper into her hidden myfteries, will more and
more place the difcoveries of thofe truths before the eyes of all, io as
to produce an averllon to the errors of former times, which all thofe
who love the truth, ought diligently to aim at. For,
We cannot in any better manner, glorify the Lord and Creator of
the Univerfe, than that, in all things, how fmall foever they appear
to our naked eyes, but which yet have received the gift of life, and
power of increafe, we contemplate the difplay of his Omnifcicnce
and Perfe(5tions with the utmoft admiration.
END OF THE FIRST VOLUME.
SIDNEY, — PRINTER, BLACK HORSE COURT, FLEET-STREET.
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