198 The Botanical Gazette. [April, 
at such a height that when the pails are in the position shown 
in fig. I, the metal rod, B, slips into the notch F, (fig. 4). 
The weight of the upper pail (which is the heavier when 
the apparatus is in use) retains the rod in this position. The 
copper strip now has the position shown in figure 4. As the 
brine flows from the upper pail into the lower, the latter 
(which hangs one and one-half inches from the base of the 
standard), becomes the heavier and settles slowly down till it 
rests on the base. This causes the wheel to turn and ther 
containing excelsior resting on the bottom of the pail. : 
The freezing chamber is clamped into the jaws of the ml’ 
en placed on the table at the left of the sic 
e flow 0 
t 
op of the chamber By means of the faucets th the tea 
brine may be r 
egulated, and this i egulates 
perature of the chamber this in turn reg 
S soon as the brine has all run into the lower pail the Pr 
