7 2 Pepper-Water . 
till at length almofl: the whole Fluid feems 
alive : though in reality they lie chiefly on 
the Surface of the Water, and go not deep 
therein, unlefs frighted or difturbed; but 
when that happens, they will fometimes 
dart down all at once, and not appear again 
for fome time. In warm Weather this Skin 
rifes on the Surface fooner, and you will 
perceive them grow fader, than in cold : 
though even in the midd of Winter, if the 
Water be not frozen, the Experiment will 
lucceed. 
About the Quantity of a Pin’s Head of 
this Scum, taken up with the Nib of a new 
Pen, or a fmall Hair-Pencil, and applied on 
a Angle Iflnglafs, fird to the third Magnifier, 
then to the fecond, and then to the firfl:, 
will fhew feveral Sorts of Animalcules lefler 
each than other, and differing a great deal 
in Shape as well as Size. 
The Sorts that have been obferved in 
Pepper-Water are, 
Firjl , The larged Sort of all (reprefented 
Plate VII. Fig. I.) •f* The Length of thefe is 
about the Diameter of a Hair, and three or 
four Times more than their Breadth. Their 
Bodies are very thin and tranfparent, but 
that Side which feems the Back is darker 
than the other. They turn themfelves in 
f Philofopb. 'Tranf. Numb. 284. 
the 
