ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 801 



Crookshank's Bacteriological Microscope. — Messrs. Swift and Son have 

 recently brought out this iustrnmcnt (fig. 208), under the instructions of 

 Dr. E. M. Crookshank, specially for bacteriological work. 



It is provided with an extra large stage with glass surface, which is 

 slotted in the centre to facilitate focusing with high powers, and the removal 

 of the slides. A modified form of the Abbe condenser, with high angle, is 

 applied to the centering substage and fine crossed lines are ruled on the 



