THE MICROSCOPE. 145 
varnish, or other cement, to guard against dampness and accidents. 
As a mounting medium it is equal to glycerin, while it is free from 
its imperfections, and is second only to balsam, which makes a little 
clearer specimen, especially if it be a wood or plant section; it 
deserves to go into general use side by side with balsam. If 
we want the solution thinner, use glycerin jelly 1 part; Farrant’s 
sol., 1 part; glycerin, 2 parts; which contains, glycerin, 67 per cent. ; 
water, 19 per cent.; gelatin, 4 per cent.; gum arabic, 10 per cent. 
This sets very slowly and does not check under; or, if we use three 
parts of glycerin, we have glycerin, 74 per cent.; water, 15 per 
cent.; gelatin, 3 per cent.; gum arabic, 8 per cent. This sets rather 
slowly, but is useful where glycerin mounting is the ideal, the small 
per cent. of gelatin and gum arabic still being enough to hold the 
medium under the cover. 
Of these three combinations I am led to prefer the first. 
PROCEEDINGS OF SOCIETIES. 
THE ST. LOUIS CLUB OF MICROSCOPISTS. 
T the meeting on March 12, Frank Davis reported on the ex- 
amination of balsam of tolu, and exhibited specimens made 
by placing a drop on a warm slide and covering it with a cover-glass. 
The specimens showed crystals of cinnamic and benzoic acids and 
parts of insects and other foreign matter. The most crystals were 
found in the balsam taken from the under side of the cover of the 
cans. Professor Whelpley showed mounts of hair from the ornitho- 
rhynchus paradoxus, and pointed out its peculiarities; also roots 
from a sweet potato sprouted in water. He demonstrated the root 
cap and explained its function. The remainder of the evening was 
devoted to the examination of specimens from the club’s cabinet. 
SAN FRANCISCO MICROSCOPICAL SOCIETY. 
REGULAR meeting of this society was held at its rooms on 
April 10th, 1889; President Poyzant in the chair. . 
Mr. Leckenby spoke briefly of the difficulties often experienced 
by the tyro in manipulating the numerous forms of insect life for 
slide-mounting and lantern projection, and proceeded to describe 
the method pursued by him as embodying the result of many years 
of patient application to the subject. Starting with the coleoptera, 
or beetle family, the first step is to devitalize them quickly and while 
