ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



161 



Reeves's Water-bath and Oven. — The arrangement of Dr. Reeves's 

 apparatus sufficiently appears from fig. 36. It is heated by a gas- 

 burner, or placed over a coal-oil flame. 



Fig. 36. 



Fig. 37. 



Doty's Balsam Bottle.— Most of the methods for the manipulation of 

 Canada balsam are open, it is said, to the objections of inconvenience, 

 wastefulness and slowness whicb Mr. Doty's bottle, 

 fig. 37, is intended to obviate. 



The reservoir B is a turnip-shaped bulb, 

 through the stopper C of which passes a wire R. 

 One end of the wire is then bent into a ring for 

 the fioger, and the other is tapered and ground 

 into the lower end of the stem of the bulb, thus 

 forming a valve V. 



In preparing for use, first put a small quantity 

 of the solvent S, which is used to dilute the 

 balsam, into the bottle D, being careful that not 

 enough is used to touch the valve ; remove the 

 wire and stopper from the bulb and close the 

 valve end ; fill the bulb with balsam diluted so as 

 to flow or drop freely, and replace the wire and 

 stopper. 



The advantages of the bottle are : — The bulb 

 can be taken from the bottle and operated with 

 one hand ; the balsam is always ready to flow 

 and will not harden at the exit of the bulb ; the 

 flow can be perfectly controlled ; it may be 

 operated continuously ; it is cleanly and durable ; 



the balsam being delivered from the lower end of the tube is free from 

 bubbles, and being always protected is free from dust. 



Eternod's Apparatus for stretching Membranes.* — Professor A. 

 Eternod's apparatus for stretching membranes consists of a nest of rings 



Zeitschr. f. Wiss. Mikr., iv. (1887) pp. 39-41 (2 figs). 



