Microscopical Essays; 123 



coloured ones are to be ftuck on the dark fide, and vice 

 verfa. 



K 2 is a pair of triangular nippers, for taking hold and con- 

 fining a large object. 



M, a convex lens, which fits the ftage by means of the long 

 pin adhering to it ; it is defigned to collect the light from the fun 

 or a candle, and to throw them on any object placed on the ftage : 

 this piece is very little ufed at prefent. 



N, a brafs Aider, into which is fitted a flat piece of glafs, and 

 a brafs Aider, containing one or two fmall concave glafles, the 

 others flat ; it is defigned to confine fmall living obj eels, and 

 when ufed is to be placed between the two upper plates of the 

 flider-holder. 



O, a glafs tube to receive a fmall fifli. See, 



V reprefents one of the Ivory-Aiders, wherein objects are 

 placed between two pieces of talc, and confined by a brafs 

 ring. 



Q, a piece to hoid the fpeculum H ; this piece is generally 

 fitted to the microfcopes which are reprefented at Fig. 1 and 2, 

 Plate IV. 



It, a pair -of forceps, to take up any occasional object, 



O 2 'S, a 



