8 ON THE USE OP 



or Brunswick black. It is better to see this done than to 

 read the best description of " how to do it." A small 

 bottle of gold size or Brunswick black costs 6d. 



Make a solution of salt and water ; be careful that it is 

 very clean, and better use distilled or filtered water five 

 grains of salt to one ounce of water. This is the best 

 preservative for palates. 



Pure glycerine a small bottle, 1*. This is excellent for 

 leaves of moss and cuticles ; but they also mount very well 

 and more easily in Mr. Topping's liquid: one part of 

 acetate of alumina to four parts of distilled water. 



Let your cells be quite dry ; it is better to make a dozen 

 or more at once and keep them by you. When required, 

 fix the slide upon the turn-table, put a drop of the liquid in 

 the cell with a camel-hair pencil, then lay the object in it. 

 Have a thin glass cover ready, and let it gently fall over 

 the cell. Remove the superfluous moisture with a little 

 sponge or blotting paper ; and then, with a steady hand, 

 take a brushful of Brunswick black, make the revolving 

 table run round quickly, and, touching the edge of the 

 cell, a circle of the varnish will safely fix it. Let the 

 varnish be thin, and the circle also; for it dries better, 

 and there is less danger of its running into the cell-contents. 

 The next day go over it again, making the circle thicker 

 and wider. 



FOR MOUNTING IN BALSAM. 



Have a bottle of clear, pure Canada balsam it costs Is. 



A little spirit of turpentine, Sd. 



Spirits of wine, one ounce, Is. 



A brass table or tripod. 



A spirit lamp. 



Solution of .caustic potash. 



The use of balsam in preparing insect parts is not only 

 to preserve, but to show the structure of the object. When 

 properly applied, it enters into the minutest parts, dis- 

 placing the air, and rendering the external tegument 

 hairs, spines, or suckers perfectly transparent. 



Eor instance, many young students, anxious to see the 



