M i c r o s c o p i c a l E s s a y s .
the more white and tranfparent day-light; and befides, either by
moving the candle or turning the microfcope, fuch light may be
varied or directed juft as the fubjedt requires.
It may be alfo proper to take notice, that no kinds o f micro-
fcopes are fit for thefe obfervations, but fuch as have an open
ftage, whereon the flips o f glafs, with the liquor upon them, may
be placed readily, and in a perfefi horizontal pofition; and
moreover, where they can be turned about freely, and without
difordering the fluid.-
* v»*
* * # * *'*• ** **
R. HIN’DMARSK,
3 * ** * * * #* o'
C H A P .
C H A P. VO
f I n s e c t s i n g e n e r a l ..
N A T U K A L hiftory has been more cultivated in the pre-
fent century than in all thofe which have preceded it.
Many men, o f the firft rank in literature, have not difdained to
become labourers in the. vaft field which this fcience offers every
day to the eyes o f an accurate and attentive obferver. The
animal, the vegetable, and the mineral kingdoms, have been
examined with the greateft care; and that confufion and perplexity,
which, from a view o f the immenfe variety o f individuals
which each kingdom contained, it feemed natural to.
apprehend, has been removed, by introducing fyftematic order
into this branch of fcience; by Which means the various individuals
have been diftributed into claffes and genera, and we are
now enabled to form diftinci and accurate ideas of them. To
the fame fyftematic plan, and the nicety of difcnmination which
arifes from it, we are indebted for the difcovery and defcription
o f many new fpecies in each kingdom..
Amidft the numerous objefts which crowd in upon the natural
liiflorian, and engage his attention, infefts hav;e not been neg-
lefted ; and though they are the moll numerous o f the animal
tribe, and for the moft part very final]; yet the knowledge o f their
nature