in length about half the diameter of the middle of their bodies.
Before he difcovered this expedient, he tried to kill them by
different kinds o f faits and fpirits ; but though they were deftroyed
by this means, their fins were fo contracted, that he could not
diftinguifh them in the leaft. After lying in this flute o f torpidity
for two or three minutes, i f a drop o f clean water be applied to
them, they will recover their fhape, andfwim about immediately,
renderinsr their fins again invifible;
It is one o f the wonders- o f the modern philofophy to have
invented means for bringing creatures, fo imperceptible as the various
animaicula, under our cognizance and infpection. One
might well have deemed an objedt that was a. thoufand. times too
little to affeft our fenfe, as perfeflly removed from human dif-
Gôvery; yet we have extended our fight over animals to whom
thefe would be mountains. In reality, the- greater number of
microfcopic animal'cula are o f To fmall a fize, that through a lens;,
whofe focal diftance is the tenth part o f an inch, they only appear
as fo many points.; that is,, their parts cannot be diftinguifh-
ed, fo that they appear from the vertex o f that lens under am
angle not exceeding the minute o f a degree. I f we inveftigate
the magnitude of luch an objefl, it will. be found nearly equal to
300006 o f an inch long. Suppoling, therefore, thefe animaicula to
be o f a cubic figure, that is, o f the fame length, breadth, and
thicknefs, their magnitude would be expreffed by the.Gube o f the
fra&ion Wfcnr, that is, by the number that is,,
each animalculum is equal to fo many parts o f a fquare inch..
This contemplation of animaicula has rendered the idea of indefinitely
fmall bodies very familiar to us ; a mite was formerly
thought the limit o f littlenefs, but we are not now furprized tabe
be told of animals many millions o f times fmaller than a mite; for
there are fome animaicula fo fmall, that, upon calculation, the
whole earth is not found large enough to-be a third proportional
to thefe little animals, and the wha e in the ocean.* Thefe con-
fiderations are ftill further heightened, by reflefting on the internal
llrufture of animaicula, for each muff have all the proportion,
fymmetry, and adjuftment of that organized texture, which is in-
difpenfibly neceffary for the feveral funftions of life, and each
mull be furnilhed with proper organs, tubes, &c.. for fecreting
the fluids, digefting it’s food, and propagating it’s fpecies.
Having thus given a general idea o f the properties o f animal-
eula, we now proceed to defcrihe the various individuals,following
the arrangements of O. F. Muller,t and giving the reader the discriminating
eharafters by which he-has diltinguilhed them« abridging,
enlarging, or altering the defcriptions, to render them in fome
inftances more exadt, in others-lefs tedious; and upon the whole
Ihope, more interefting to the reader.
~ im
A METHODICAL DIV I S I O N OF THE ANIMAL' CULA INFUSORI AI.
Thofe that have no external organs.
A. Monas : punfliforme. A mere point.
2. Proteus : mutabile. Mutable..
3. V o lvo x ;
* Cyclopedia Britannica, Art. Animalcule;. '•
t Müller Animaicula Infuforia, Fluviatilla et Marina;