ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



897 



size, are held on the stage by a spring cylinder-clip having two 

 lateral projecting pins which slide in right-and-left bayonet slots ; 

 the clip can be raised by the pins and keyed in the bayonet slots by 

 a slight lateral turn when the slides are being put in or removed. 

 The coarse adjustment is effected by sliding the tube ; the fine adjust- 

 ment by moving the draw-tube in or out, a plan which is far more 

 convenient in practice than we shoiild have anticipated. We have 

 found no difficulty in focusing the l-8th objective in this manner 



Fig. 159. 



either with the Microscope on its tripod and the light reflected from 

 the mirror, or by pointing the body-tube directly to the sky; and 

 doubtless with a little practice the l-16th could be used with the like 

 facility. By the addition of adapters the objectives could of course be 

 used on full size Microscopes. The three high powers are provided 

 with correction adjustment. We understand that the Microscope was 

 constructed wholly by Mr. M, Swift (fig. 158 ^ scale, fig. 159 f scale). 



Mirand's Revolver Microscope. — This Microscope, by J. Mirand, 

 jun., is a further extension of the principle on which Klonne and 

 MuUer's instrument was based (Vol. III., 1880, p. 144). 



In the latter form the circular stage held eight objects on ordinary 

 slides, which could be successively brought into the field on rotating 

 the stage. In the new form the stage can not only be rotated on its 

 centre, but moved from back to front and vice versa, so that its centre 

 does not coincide with that of the pillar. With this plan each of 



