J. TATHAM ON USE OF ORDINARY BINOCULAR FOR DISSECTING. 207 



in sea water ; and thus, the mechanical adjustments of one's 

 larger and more delicate instrument are preserved from harm. 

 The advantages that may be claimed for this " adaptation," 

 which by the way may possibly be as well known to some 

 others as to myself, are as follows : — 



1. The use of the simple form of microscope, with all the 

 discomforts incidental thereto, is avoided, and the binocular is 

 available in place of the single tube. 



2. The same "hack" microscope may be used, either for 

 ordinary high power work or for dissecting purposes, by simply 

 transferring the object and the sliding clip from the ordinary 

 to the supplementary stage. 



3. An instrument of relatively small size, and consequently 

 with short rack work, may be used with long focus lenses, 

 which otherwise can only be used in connection with full-sized 

 stands. 



4. An instrument such as the one I show this evening can 

 be used with very great comfort in the sitting posture, with the 

 arms and wrists resting on the inclining planes above described. 

 This would be impracticable with a full-sized stand racked up 

 so as to focus a three or four-inch power on an object lying on 

 the ordinary stage. 



