Microscopical Essays. 



O a long fteel wire, with a fraall pair of pliers at one end, and 

 a point at the other, defigned to flick or hold obje£ts ; it flips 

 backwards and forwards in the fhort tube o ; the pin p fits into 

 the hole of the Rage. 



W a little round ivory box, to hold a fupply of talc and rings 

 for the Aiders, 



Z a hair brufli, to wipe any duft off the glades, or to take up 

 by the other end a drop of any liquid. 



V a fmall ivory cylinder, that fits on the pointed end of the 

 fteel wire O ; it is defigned for opake objects. Light-coloured 

 ones are to be fluck upon the dark fide, and vice verfa. 



Y a common magnifying glafs, for any occafional purpofe. 



M a nfh-pan, whereon to fallen a fmall fim, to view the cir- 

 culation of the blood : the tail is to be fpread acrofs the oblong 

 hole at the fmall end, and tied faft, by means of a ribband fixed 

 thereto ; the knob 1 is to be fhoved through the flit made in the 

 ftage, that the tail may be brought under the magnifier. 



The Description and Use of Adams's improved double 

 and single Microscope, representeb Fig. l, Plate IV. 



It is the compound mierofcope, which is at prefent in moll 

 general ufe. The improvements, though few in number, are 

 effential to the ufe thereof. The field of view is confiderably 

 larger than in the former microfcope. The ftage and the mirrors 



L 2 are 



