PLATE XVIII 
( $2r.) 
Obfervations communicated to the Publier by Mr. Antony van 
Leewenhoeck, én 4 Dutch Letter of the 9th of O&ob. 1676, 
here Englify’d: Concerning little Animals by hire obferved in 
Rain- Welle Sea- and Snow-water ; as alfo in water wherein 
Pepper hadlain infufed. 
N the year 1675.1 difcover’d living creatures in Ra'n water, 
which had ftood but few days in anew earthen pot, glafed 
blew within, This invited me to view this water with great at- 
cention,efpecially thofe little animals appearing to me cen thou- 
fand times lefs than thofe reprefented by Monf. Swamerdam, 
and by him called Water-fleas or Water-dice, which may be per- 
ceived in the water with the naked eye, 3 
The fir fore by me difcover’d in the faid water, I divers 
times obferved to confit of 5, 6,7, or 8 clear globuis, without 
being able to difcern any film that held them together, or con- 
tained them. When thefe amimaicula or living Atoms did move, 
they put forth two little horns,continually moving themfelves: 
The place between thefe two horns was flat, though the reft of 
the body was roundifh,fharpning a little towards che end,where 
they hada tayl, near four timesithe length of the whole body,of 
the thicknefs (by my Microfcope) ofa Spiders-web ; at the end 
of which appear’d a globul, of the bignefs of one of thofe which 
made up the body; which tayi I could not perceive,even in ve- 
ry clear water, to be mov’d by them. Thefe little creatures, if 
they chanced to light upon the leait filament or ftring,or other 
fuch particle, of which there are many in water,ef{pecially after 
it hath ftood fome days, they {tock intangled cherein,extending 
their body ina long round, and ftriving to dif-intangle their 
tay] ; whereby it came to pafs, that their whole body lept back 
towards the globul of the tay], which then rolled together Ser- 
pent-like, and after the manner of Copper- or Iron-wire that 
having been wound abouta ftick, and unwound again, retains 
thofe windings and turnings. This motion of extenfion and 
contraétion continued a while; and I have feen feveral hun- 
dreds of thefe poor little creatures, within the fpace of a grain 
of profs fand, lye faft clufter’d together ina few filaments. 
Lalfo difcover’d a fecond fort, the figure of which was ova! ; 
and I imagined their head to ftand on the tharp end.Thefe were 
a little bigger than the former. The inferior part of their body 
is flat, furnifhed with divers incredibly thin feet, which pyar 
FIRST PAGE (FACSIMILE) OF OLDENBURG'S TRANSLATION OF LETTER 18 
(9 Oct. 1676) published in Phil. Trans. (1677), Vol. XII, No. 183, 
pp. 821-831. Compare with Plate XIX. 
facing p. 1138 
