68 HOW TO SEE WITH THE MICROSCOPE. 



lique light, coarse adjustment by rack and pinion, fine 

 ditto, by delicate screw, diaphragm; draw tube gradu- 

 ated, with society screw at end. The instrument can 

 be inclined to any angle, has English horseshoe base, 

 and is sixteen inches high when arranged for use. 



BULLOCK'S NEW BIOLOGICAL STAND. 



The cut shows the instrument about two-fifths the 

 real size, it stands twelve and a half inches high, and 

 the stage three and a half from the table when in an 

 upright position. Body tube five inches long, draw 

 tube five inches long; with marked ring when drawn 

 to the standard length. Standard size and sub-stage 

 fitting, adapted in sub-stage with the society screw for 

 the use of objectives as condenser, and the diaphragm 

 fits in the same screw and can be used 1 close up to the 

 object slide. Plain and concave mirrors each swing 

 over the stage can be used together, or separate, can 

 be clamped in any position, by milled screws shown 

 behind the limb. Spring 'stop to mirror and sub-stage 

 when in line axis. Concentric revolving stage, can 

 be adjusted concentric to the axis by means of capstan- 

 head screws, the sub-stage also can be adjusted con- 

 centric by means of capstan screws. Spring clips to 

 stage or the sliding glass stage as desired. 



When the stage is not required to revolve, it can be 

 clamped in any position by the milled screw shown in 

 front; and when there is any danger of injuring the 

 stage by the use of acids, the stage lifts out of the ring 

 in which it revolves, and any" ordinary piece of glass 



