for Opake ObjeBs . 29 
when the leaft Magnifiers are employed.— 
This Ring receives the Screws of all the 
Magnifiers. 
K. a concave Speculum of Silver, polifh- 
ed as bright as pofiible, in the Center of 
which a double convex Lens is placed, with 
a proper Aperture to look through it. 
On the Back of this Speculum a male Screw 
L. is made fit to the Brafs Ring I. to fcrew 
into the faid Ring at Pleafure. 
There are four of thefe concave Specula, 
of different Depths, adapted to four Glaffes 
of different magnifying Powers, to be ufed 
as Objedts to be examined may require. 
The greatefl Magnifiers are known by 
having the lead Apertures. 
M. a round Objedt-Plate, one Side white 
and the other black, intended to render Ob¬ 
jects the more vifible, by placing them, if 
black on the white, and if white on the 
black Side. A Steel Spring N. turns down 
on each Side to make any Objedfc faff : and 
iffuing from the Objedt-Plate is a hollow 
Pipe, to fcrew it on the Needle’s Point G. 
O. a fmall Box of Brafs, with a Glafs on 
each Side, contrived to confine any living 
Objedt,in order to examine it: this alfohasa 
Pipe to fcrew upon the End of the Needle G. 
P. a turned Handle of Wood, to fcrew 
into the Infirument when it is made ufe of. 
a a Pair of Brafs Flyers, to take up any 
Objedt, or manage it with Conveniency. 
§ R. a 
