28 Nebraska Agricultural Exp. Station Research Bul. 1G 
conditions: (1) Artificial freezing under control conditions; 
and (2) natural freezing of corn standing in the field under 
prevailing natural conditions. 
VITALITY OF CORN FROZEN UNDER CONTROL CONDITIONS 
APPARATUS 
The low temperatures used in these experiments were secured 
under control conditions by the use of a freezing mixture of 
salt and ice. By mixing the salt and ice in the proportion of 
one part of salt to two parts of ice a temperature of — -5° F. 
was secured. In order to secure the various ranges of tempera- 
ture and to maintain those temperatures for several hours, two 
different devices were used. 
For temperatures above zero, an insulated freezing box was 
made. The essential parts of this box are: (1) A compartment 
for containing the freezing mixture. This was large enough 
to hold about two hundred pounds of crushed ice. (2) A com- 
partment for containing a strong salt solution and a freezing 
cell. This compartment or chamber was large enough to hold 
twenty gallons of brine. (8) A freezing cell into which the 
material was put for freezing. This cell was cylindrical in 
shape 5 inches in diameter and 18 inches deep, with capacity 
for sections from 30 e^rs of corn. (4) A series of connected 
cells in the freezing mixture compartment. This series of cells 
was connected with the brine chamber in such a way as to allow 
the cells to fill with brine. (5) A pump for circulating the 
brine thru the cells and back into the brine chamber. (G) A 
thermometer to indicate the temperature in the freezing cell. 
The working principle of this device was somewhat as 
follows: The freezing mixture of salt and ice was packed 
around the series of brine cells. This reduced the temperature 
to 0° F. or below in this chamber, and cooled the brine in the 
cells. The brine was made strong enough so that it would not 
freeze at this temperature. The corn was then placed in the 
freezing cell, the lid closed, and the thermometer inserted. 
When all was ready, the pump, operated by an electric motor, 
was starred and the chilled brine from the series of cells was 
forced into the large brine chamber and other brine drawn into 
the cells to cool. Bv this method the twenty gallons of brine 
was gradually cooled to the desired temperature. As soon as 
the desired temperature was secured, the pump was stopped. 
The large volume of brine which surrounded the freezing cell 
maintained a comparatively even temperature in the latter for 
several hours. 
