ZOOLOGY AND BOTANY, MICEOSCOPY, ETC. 



Ill 



be rotated completely round the stage, so that the direction of the 

 illumination in azimuth can be more readily varied than is the case 

 with Zentmayer's form of tail-piece. 



The stage consists of a fixed ring attached to the limb by an 

 angle-plate of brass ; this ring carries above it the rotating object- 

 stage, and beneath a rotating collar is fitted, which has a shoulder 

 attachment at right angles carrying the two tail-pieces on an axis 

 slightly above the plane of the object-stage, and allowing of their 

 rotation round the optic axis. The angle-plate, by which the stage- 

 ring is fixed to the limb, is so arranged that the shoulder carrying the 

 tail-pieces will pass behind it, and there is therefore no obstruction to 

 complete rotation. 



This plan of suspending the tail-pieces is far more convenient 

 than that devised by L. Jaubert,* or that of J. Mackenzie.-]" 



McLaren's Microscope with Rotating- Foot.— -Mr. A. McLaren 

 has devised a simple plan of giving greater stability to Microscopes 



Fig. 9 



mounted on a pillar support on a horse-shoe foot, which are very 

 liable to be overturned when much inclined from the perpendicular. 

 The plan consists in making the foot rotate at its junction (fig. 9, A) 



* See this Journal, i. (1881) pp. 514-5. 

 t Ibid., pp. 825-7. 



