A simple freezing device. 
WINTHROP JOHN VAN LEUVIN OSTERHOUT. 
ae apparatus consists of a freezing chamber upon which 
€ object is frozen, and two pails filled with ice and salt. 
by through the freezing chamber which is between the pails 
a cied with them by rubber tubing. 
is ef freezing chamber is a hollow cylinder made of brass 
* tron, nickel-plated both inside and outside. Fig. 1 
shows a section of the chamber, 
actual size. The brine enters one 
of the tubes at the side and es- 
capes by means of the other. Be- 
low the bottom of the chamber, 
D, the cylinder is furnished with a 
thread inside, by means of which 
a wooden plug, C, is screwed firm- 
ly against the bottom of the cham- 
ber. The wooden plug is held se- 
curely in the jaws of the microtome 
and prevents the conduction of too 
much heat from the latter to the 
Pails are Reo is to be used for a short time only. Paper 
be used sector the purpose, but ordinary wooden ones can 
- Each pail should be provided with a faucet capable 
tter: the "id @ stream of water one-quarter of an inch in diam- 
tom of ae Should be inserted about an inch from the 
Use answer +h pei Ane paper ice-water pails in common 
In Order © purpose perfectly. 
‘theres to ms Prevent the dirt, straw, etc., which usually 
Piece of ...... (© from passing into the freezing chamber a 
ont wire netting should be bent into the form of 
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