100 



THE MICROSCOPE. 



the process will have to be reversed, by first finding this 

 particular square on the finder, and then replacing it by 

 the object-slide. 



A simple form of finder, suggested by Mr. W. K. Bridge- 

 man, of ^Norwich, and sold by Baker, Holborn, is, from 

 its ingenuity and comparative accuracy, worthy of notice. 



Fig. 112. — Bridgeman's Finder. 



This finder (fig. 112) consists of a curved pin of steel, 

 which is attached to the stand by means of a circular 

 fitting of brass. It is so contrived that when the mechanical 

 stage is brought into the rectangular position, and an 

 object laid thereon, it can be pressed down upon the slide. 

 If the latter be covered with paper, the point of the pin 

 leaves a slight puncture : all that is necessary, when we 

 wish to examine the object in future, is to move the stage 

 till the puncture on the slide comes under the point of 

 the finder. 



Forceps. — For holding minute objects, such as parts of 

 plants or insects, to be examined either as transparent or 

 opaque objects, the most useful is represented by fig.l 13, 



s — 1 



A«J 



Fig. 113. 



and consists of a piece of steel wire, about three inches 

 long, which slides through a small tube, connected to a 

 stout pin by means of a cradle-joint ; to one end of the 

 wire is attached a pair of blades, fitting closely together 

 by their own elasticity, but which, for the reception of any 



