THE SIMPLE MICROSCOPE. 



61 



nally, one of which is seen at s, this elevated stage can 

 be moved in two directions, at right angles to each other, and 



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Fig. 38. 



the different parts of any object can be brought successively 

 into the field of view. 



The arm, n p, which carries the lenses, is attached to the 

 triangular bar, rf, by a conical pin, on which it can turn hori- 

 zontally, and the arm itself can be made longer or shorter by 

 means of a rack and pinion, m o, attached to it, hence the 

 lens, q, may be applied to all parts of an object without 

 interfering in any way with the stage. 



The mirror, I, is placed upon the largest of the three legs 

 forming the tripod, and consists of a concave and plane glass 

 reflector. To the under side of the stage is fitted a Wol- 

 laston's condenser, k, and the lens is made to slide up and 



