954 SUMMARY OF CURRENT RESEARCHES RELATING TO 



carrying with it the wliole of the upper part of the instrument, the 

 mirror remaining stationary. We imagine, however, that this move- 

 ment is the result of defective workmanship, and was not designed 

 as a means of providing oblique illumination. 



Schieck's Corneal Microscope. — This (fig. 146) was designed by 

 F. W. Schieck for the examination of the cornea. A steel standard 

 (16 in. long) is secured to the table by a screw clamp. On it slide 



Fig. 146. 



two arms which can be set at any required height by screws. The 

 upper short arm carries the Microscope, which is connected with it by 

 a ball and socket joint and clamp screw, so that great range of motion 

 is obtained. A rack and pinion serves for focusing. 



The lower arm carrying the condensing lens consists of two rods 

 connected by a double ball and socket joint. The lens moves on a 

 hinge and also rotates on the rod, a small screw, the point of which 

 works in a groove encircling the end of the rod, preventing it from 

 slipping off. For the lens a mirror having the same movements can 

 be substituted. 



Zeiss's No. X. Microscope. — This (fig. 147) is noticeable mainly for 

 the manner in which the upright support is constructed. The limb 

 is of the " Jackson " form, but is continued to the base, to which it is 



