268 THE MICROSCOPE. 
moderately distended the end in which the injection is made is 
tied and the piece of intestine placed in a glass dish and covered 
with the mixture. After one or two days the muscular coats may 
be torn off in shreds. If one of the shreds is teased well with 
needles, unstriated muscular fibers may be partly or wholly iso- 
lated. They may be mounted in seventy-five per cent. glycerin. 
The picric acid stains the fibers yellow and with a homogeneous 
immersion (1-12th or 1-18th) the longitudinal fibrillation shows 
with the greatest clearness. In some cases the ends of the fibers 
will be frayed and show the fibrillae something like a brush. 
ANATOMICAL LABORATORY OF CORNELL UNIVERSITY. 
November 1, 1886. 
A SIMPLE POLARISCOPE. 
R. W. WOOD, JR. 
OR the benefit of those whose financial state is such as to 
prevent the outlay of fifteen or twenty dollars, for a first-class 
polariscope, I will give a few hints for the manufacture of one at 
the modest price of fifteen or twenty cents. 
As microscopes differ in build it will be useless to give any 
very explicit directions, and I shall simply describe the method by 
which I made mine, trusting to the ingenuity of the reader to 
modify the construction to suit his or her instrument. 
The polarizer is 
nothing more than a 
piece of black glass 
(glass backed by a 
=\" black, enamel-like var- 
=f nish) substituted for 
the mirror. 
If your mirror is 
ae ae mie OO ABE = single, cement the 
black Manes ut 4p the proper size, to the back; if double, attach the 
plate so that it can be removed at pleasure. 
The analyzer requires more care and must be adapted to the 
microscope. 
My microscope tube unscrews about half way down or in 
other words “ Breaks in two in the middle.” 
I made a paper tube, with a wall $ of an inch thick, which 
