1897 THE MICROSCOPE. 107 
Demonstration of Living Trichinae.—A piece of trichi- 
nized muscle the size of a pea should be placed in a bottle 
in a mixture of three grains of pepsin, 2 drams of water, 
and 2 minims of hydrochloric acid. The whole should be 
kept at a body temperature for about three hours with 
occasional shaking. ‘The flesh and cysts being dissolved 
the fluid is poured intoa conical glass, and allowed to set- 
tle. The trichine are drawn off from the bottom witha 
pipette. Place them on a slide with water and examine 
ona hot stage. Never allow the fingers to touch trichin- 
ized flesh and, after handling, scrupulously clean all your 
instruments. 
White Zinc Mounts.—Many workers discredit white 
zinc for mounting. The following method has stood the 
test of time and can be recommended as reliable. Prepare 
a lot of slides at one time and keep them on hand. Do not 
use the ring when first made. Procure a capsule of white 
zinc froma dealer in painter’s supplies. From the same 
source procure a bottle of refined linseed oil. Squeezea 
little of the contents of a capsule into a plate or upon any 
hard, smooth, clean surface and with a spatula rub it with 
a drop of the linseed oil until the mass is plastic and hom- 
ogeneous. It is now ready for use. Witha brush, turn 
rings the size desired and when finished set the ringed 
slide away until it becomes hard. In using these rings 
for glycerine mounts, fill full, cover, turn a ring to hold 
the cover. If the first rings be not sufficient, set the slide 
away for a day to harden and then build up, successively, 
rings of sufficient thickness. I have glycerine mounts 
fifteen years old that are perfect. 
SeGleENiGiE = G:OSosik Re 
The Microscope Merits Wider Use.—Having made a 
specialty in the analysis of urine for physicians, I have 
found the microscope an indispensable instrument at times 
when examinations were necessary after testing the urine. 
In cases where albumen was found and it did not altogether 
