66 



The "Popular Microscope." 



bottom of the tube H is a pin that fits into any of the boles 

 in tbe base. If this [pin is inserted into the bole near L, 

 tbe instrument is held upright or vertical. If into the hole at 

 the top of the little support, K, it is horizontal, as shown in 

 Figure 2.* The other holes permit it to be adjusted in in- 

 termediate positions. The me- 

 chanical effect of this arrange- 

 ment is to give great stability 

 with very little weight. The 

 coarse and fine adjustments, 

 0, 0, and P, need no explana- 

 tion. 



In the construction of the 

 two stages supplied with this 

 instrument, much ingenuity 

 has been usefully exercised. 

 One of these stages is in- 

 tended for finger movements, 

 the other has mechanical mo- 

 tions on an entirely new plan. 

 Both stages are 

 circular. They fit 

 on to a short 

 stout piece of 

 tube, and can 

 be rotated with 

 slight pressure. 

 It appears to us 

 that this plan, 

 with mechanical 

 arrangements for 

 rotation, might 

 be adapted with 

 advantage to 

 first-class instru- 

 ^ ments. It is 

 WUk compatible (as in 

 = the Popular Mi- 

 croscope) with a 

 thin stage and a 

 large central aperture, facilitating the use of oblique light. 

 The object-holder is attached to the under surface of the stage 

 by a simple circular spring, and holds it down with a force 

 that is easily regulated by two screws. By this means the 

 pleasant smooth resistance afforded by the magnetic stage 



* The page containing Tig. 2 must be turned sideways, to bring the figure 

 right. 



