COLLECTION OF SPECIMENS 155 



ease and precision with which dissecting work 

 can be performed by its aid, and the relief given 

 to the eyes by its use a matter of no small 

 moment when it is remembered that the dissect- 

 ing and mounting of specimens frequently involve 

 much close and continuous application. Another 

 simple but convenient instrument for the like 

 purposes is the ordinary watch-maker's glass, set 

 in a deep horn mount, by means of which it can 

 be retained in position in front of the eye, and 

 this is particularly useful in such an operation as 

 the extraction of air-bubbles from a specimen 

 about to be mounted; care must, however, be 

 taken that at the critical moment the muscles 

 round the eye are not relaxed, and the glass 

 precipitated on to the proposed mount ! 



For soaking plants in hot water, preparatory to 

 dissection or mounting, there is nothing so handy 

 as the small china saucers which are used by 

 artists, and which can be obtained, of various 

 sizes, from any artists' colourman. Dissecting 

 instruments of various forms are sold, but the 

 simplest, and to my mind most effective, imple- 

 ments may be constructed by the student himself 

 at a trifling cost, and with very little trouble. 

 Sail needles and glovers' needles (No. 4) make 

 the most admirable dissecting tools; the former 

 may be procured at an ironmonger's, the latter 

 from a draper. Each kind of needle is not only 

 provided with a good point, but is ground with 



