l.-)4 



BROWN, ON MICROSCOPICAL MANIPULATION. 



cell, and counter-sunk to the diameter and thickness of the 

 cylinder glass. 



In using this plate I apply sufficient indirect heat to it, and 

 rub over each of the counter-sunk portions some sealing wax 

 or shellac ; immediately pressing down into each, upon the 

 softened wax, the thin glass circles. When cold, the centres of 

 each may be easily removed by perforation with a rat-tailed 

 file, and trimmed round with a finer (watchmaker's) file to 



the exact diameter of the perforation, the counter -sinking 

 giving the exact centering. The plate may again be heated 



and the cells slid off into 

 ether, in order to remove 

 the wax and cleanse them. 

 This plate is made with 

 tolerable rapidity and ac- 

 curacy on a lathe with an 

 eccentric chuck. I have 

 also drawn a description of 

 forceps that I find very 

 useful in preparing micro- 

 scopic objects, where it is 

 of importance to have 

 gentle pressure, easy of ap- 

 plication, with, at the same 

 time, a facility for occa- 

 sional inspection, as, for 

 instance, in preparing the 

 proboscis of a fly for 

 mounting, and in cases 

 requiring the like treat- 

 ment. These are almost 

 identical with the forceps 

 used in artificial fly-dres- 

 sing, but having cemented 

 to their extremities two 

 slips of thin glass, may be 

 brought at any time under 

 the held of the microscope. 

 I have obtained the same 

 result from an American 

 clothes peg, fitted with glass in the same way. 



