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consistency for easy working by the addition of their respective 

 diluents, are required : gold-size, caoutchouc cement (Miller's), 

 and Club black. As a mounting medium, use equal parts of 

 whisky and glycerine. This should be carefully filtered, or else 

 allowed to stand for a few days, and then decanted. Place a 

 slip on the turntable, and run upon it a ring of gold-size |-in. 

 diameter. Take a cell, and, by means of a pair of forceps, drop 

 it on the ring of gold-size, pressing down to ensure good contact. 

 Prepare a number of these slips, using cells of different depth, 

 and put aside for a week to dry. 



Take the whisky-soaked palpus and place it in one of the 

 deepest cells, fill up with whisky, and place a temporary cover- 

 glass upon it, holding it in position with a wire clip. Now turn 

 the slide about and observe what happens. If the cell is very 

 deep compared with the thickness of the object, this latter will 

 fall to the side. If somewhat shallower, the object will only 

 reach the margin, or near to the margin, of the now practically 

 invisible excavation in the slip. Try cells of various depths until 

 one is found which produces the desired result, which is to keep 

 the object perfectly still, or else to allow it only a certain amount 

 of movement. The proper slip having been found, it is thoroughly 

 cleaned, placed upon the turntable, and a ring of caoutchouc 

 cement run upon the upper surface only of the tin cell, and then 

 allowed to dry for, say, a quarter of an hour. The cell is filled 

 to overflowing with the glycerine-and-spirit mixture, the dis- 

 section is introduced and arranged, and a cover -glass put on 

 and held in position with a weak wire clip. The whole is held 

 under a gentle stream of water from a tap, in order to get rid 

 of every trace of glycerine from the glass. The success of the 

 process depends upon this being thoroughly accomplished. To 

 avoid the inrush of a bubble of air when the clip is removed, 

 perform this operation under water, and allow the slide to 

 remain submerged for a few minutes. A small quantity of 

 water will enter, but will not in the least impair the mounting 

 medium. The mount is then wiped as far as possible, allowed to 

 dry thoroughly, a ring of gold-size is added, and, a couple of days 

 afterwards, a ring of Club black. In a considerable number of 

 preparations, dating back for more than two years, not one 

 air-bubble has penetrated, in spite of a good deal of very rough 

 usage. 



