Researcli Lahoratory of the Royal Colkye of Fhysicians. 5)31 



filled in by means of an india-rubber bag (Nachet's plan), 

 fixed by wire to a flange around the opening and by 

 a nut with a washer around the clamp rod. The tray 

 is filled with spirit which cannot escape except by special 

 taps, but the specimen can be raised by means of the 

 screw, the india-rubber bag allowing considerable move- 

 ment but preventing the escape of the spirit. At one 

 corner of the tray is a grating with a tap beneath (d), by 

 which the spirit may be drawn ofi\ whilst in the india- 

 rubber bag there is also a tube (e) with a Mohr's clip 

 through which the remainder of the spirit may be removed. 

 At each end of the body of the microtome is a ring with a 



-S7 FT, 

 TOP FLAT 



Fig. 11. 



binding screw in which a rod may be tixed to prevent the 

 knife point or heel coming in contact with the ends of the 

 tray. We have found this a most convenient arrangement, 

 especiall}'- for large sections 3 or 4 inches square. Mr 

 Hume gave me very great assistance in working out the 

 details of the above piece of apparatus, the workmanship of 

 which does him great credit. 



Next door on this same flat is a small room used as a 

 store for reagents and other chemicals ; the window is 

 fitted with a table for microscopic work. Then comes 

 another small histological room, and lastly a room set apart 

 for the estimation of urea, albumen, and sugar in urines, in 



