88 M i c r o s c o p i c a l E s s a y s .
A brafs cone to place under the Aider-holder.
The jointed nippers.
A cylinder o f ivory, to fix on the pointed end of the nippers.
Six ivory Aiders, five of which are filled with objects.
A magnifier for the hand.
A fifh pan.
A round brafs box, with glafs ends, for confining living objects.
An ivory box, to hold fpare rings and talc for the Aiders.
A round fiat glafs, fitted to the hole in the ftage.
A concave ditto.
A Aider o f brafs, containing a fiat glafs Aider, and a brafs Aider,
into which are fitted fmall concave glafies.
Some glafs tubes.
A fmall pair o f forceps.
A Aip or two o f flat glafs.
A fmall brufh, or hair pencil.
The
The ufe o f each article o f the apparatus, and the method o f
applying it to ufe, will be defcribed in the latter end of this
chapter.
O f the improved Compound Microscope, represented
a t Fig. 2, Plate IV.
The advantages o f this over the preceding compound micro-
fcope, confifls, firft, in the motion which may be given to the
body, the ftage, and the mirrors, by means o f the joint c d,
which has both a vertical and'horizontal motion; fo that the
microfcope may be placed either in an horizontal or inclined
lkuation, and thus be. adapted to the eafe of-the obfetver, and
be ufed when he is fitting down. If the mirror Q O R is
taken off, the' light will be conyeyed in a direct line to
the objeft, without any reflection. Secondly, that the body may
be moved over any part o f the ftage, and thus over the objeft.
The arm which carries the body, moves to the right or left on a
central pin, and.may alfo be moved backwards or forwards by the
milled nut b. Thirdly, the concave and flat mirrors are. much
larger than thofe o f Fig. 1. In every other refpeft, the microfcope
is ftmilar to the foregoing, and m&y be managed by the
defcription thereof; for which purpofe, fimilar letters are affixed
to the fame parts.
A D escription of Culpeper's, or the thr'ee^pillared
Microscope, Fig. 3, Plate IV.
This inflrument is recommended by it’s fimplicity and cheap-
nefs; it is eafily managed, and gives a pleahng view of an ob-
M Je a -