8 PL A hae I. 
It muft be granted that, but for the microfcope, the wonders of 
®ae minute creation, would be to us entirely unknown; our ideas could 
never fuppofe the exiftence of thofe animated forms which occupy 
the immeafurable fpace between an apparent atom? and nothing. The 
myriads of animals, thoufands of times {maller than a mite, mutt 
evade our cognizance, and be an aétual conviction of their non- 
exiftence. 
But with all the utility that the microfcope can boaft, no inftru- 
ment is fo likely to miflead the moft accurate obferver, particularly 
if not in the habit of ufing it ; the variations of light, the difference of 
the magnifying powers, or the damage the glafles may meet with by 
accident, fuch as requires every one to examine with the greateft care; 
one degree of light may bring an objeét to view, whilft another may 
entirely blend it with the fluid it exifts in; or one glafs may difcover 
{pines on an objeét, another glafs might have reprefented perfeétly 
{mooth ; it is therefore neceffary to begin with a {mall power, in pro- 
portion to the fize of the obje&t, and to proceed to deeper mag~ 
nifiers after. 
There is fome difference in our figure, and thofe either of Barbut, 
or of Baker, which appears chiefly from our ufing a fingle lens nearly 
of the deepeft power convenient to ufe. Our glaffes were the 20th 
and 30th of an inch focus. 
We very attentively examined the eyes, and found, not one, but 
‘two, placed near each other, on a fecale or plate of a black colour: 
= 
hence arifes the appearance of a fingle eye by a {mall magnifying 
power. ‘ 
The tail prefents a forked appearance by a deep power, and the 
eggs are contained in two bags, one on each fide the tail. The coz: 
lour varies probably in proportion to the nature of its food 
to pale 
green, more or lefs of a red, or of a grey brown colour 
Fie: 
