NACHET S STUDENT S MICROSCOPE. 



GO 



Fig. 37. 



greatest obliquity can be transmitted to the object from beneath. 

 The rotating plate is furnished with a projection at the back, to 

 which is attached a strong V-shaped pair of springs, having their 

 extremities armed beneath with small ivory knobs, which press 

 down on the Object-carrier. This last consists of a brass frame 

 furnished with tongues 

 and springs projecting 

 forward for the recep- 

 tion of the slide, and 

 also with a pair of knobs, 

 to which the fingers may 

 be applied in giving 

 motion to it ; whilst the 

 frame encloses a piece 

 of plate-glass a little 

 thicker. than itself. Thus 

 the under surface of the 

 glass plate of the Object- 

 carrier slides over the 

 upper surface of the cir- 

 cular glass Stage-plate ; 

 being held down upon it 

 and retained in any posi- 

 tion by the pressure 

 of the ivory knobs. In 

 the perfect facility with 

 which the object-carrier 

 may be moved, and the 

 steadiness with which it 

 keeps its place when not 

 unduly weighted, this 

 arrangement is at least 

 equal to the Magnetic 

 stage, M-hilst superior to 

 it in the essential parti- 

 cular of not being liable 

 to derangement from 

 rust ; having also the 

 further advantage of be- 

 ing capable of ready re- 

 adjustment in case the 

 movement should be- 

 come too easy, nothing 



Cachet's Student's Microscope. 



more being necessary to tighten it in any required degree than 

 bending down the V springs. The front portion of the rotating 

 plate bears a small projecting piece on either side, into which may 

 be screwed a pin that carries a sliding-spring ; this arrangement 

 is suited for securing a Zoophyte-trough or other piece of appa- 



