ZOOLOGY AND BOTANY, MICIJOSCOPY, ETC. 



729 



tion, and a double mirror of 55 mm. diameter. The whole illuminating 

 apparatus is moved by rack-and-pinion motion, and remains perpendicular 

 tojthe stage of the Microscope. There is a revolving nose-piece for 

 three objectives. 



Voigtlander and Sons' Stand IVa.*— This stand (fig. 113) has in- 

 clination to 45° only, and is fitted with a handled tripod foot. There is 



Fig. 112. 



Fig. 113. 



a rack-and-pinion coarse-adjustment. The older form of micrometer 

 fine-adjustment with division of the milled head in (Vol mm. is used. 

 The outer tube is :!() mm. in diameter and has a sliding draw-tube. The 

 rectangular vulcanite stage is 85 X 95 mm. and the douljle mirror is 

 50 mm. diameter. There is a revolving triple nose-piece. The con- 

 denser is ordinary (X. A. 1 • 20) with fixed iris diaphragm, four diaphragms, 

 and carrier for a blue or ground glass disk. The condenser has a side- 

 screw adjustment. 



Fig. 114, 



Voigtlander and Sons' Magnifiers.f — Their Steinheil loups are made 

 in six powers, viz.: 7-5, lu, 12, 18, 25, and 35. They may also be 

 obtained in clasp mountings and fitted with a micrometer divided in 

 0-1 mm. (fig. 114). 



* Catalogue (English Edition) 1907, p. 32. f Tom. cit., pp. 14, 15. 



