INVERTEBKATA, CRYPTOGAMIA, MICROSCOPY, ETC. 



883 



Fig. 98. 



elevates the stage above the horizontal position as much as it was 

 formerly inclined below it. 



We should, have supposed that whatever advantage might be 

 gained by being able to use a high power with this instrument would 

 be lost by the defective adjustment. 



A still cheaper and still more barbarous method is shown in 

 Fig. 98, in which the screw beneath the 

 stage elevates the upper of two plates of 

 which the stage is composed ; the upper 

 plate is, however, only separable from the 

 lower plate at one side, so that in this 

 case also the object would not lie hori- 

 zontally, but obliquely; indeed, by reason 

 of its thinness the upper plate in our 

 instrument is more or less curved when 

 separated. 



It is perhaps fair to note that, when 

 literally translated, these adjustments are described by the relative 

 term of '^ finer," and that they are very cheap. 



Fig. 100. 



Fig. 99 



Fig. 101. 



Seibert and Krafft's Fine Adjustment. — It is claimed for this 

 contrivauco that it acts without friction. Thiio difforcnt forms arc 

 shown in Figs. 91), 100, 101. 



3 M 2 



