MANUFACTURE OF Mink Powprr 297 
admitted near the bottom in the center of the drying chamber, 
means for heating the air, blowing it into the drying chamber 
and screens located near the bottom at the periphery of the 
chamber for discharging the spent air are provided. 
In this apparatus the sprayed milk falls from near the top 
of the drving chamber through an ascending current of heated 
air. ‘Phe milk spray entering on all sides causes an even distribu- 
tion of the spray particles and a consequent even deposit of the 
dried milk particles on the bottom of the drying chamber. The 
previously condensed milk is sprayed into the drving chamber 
while heated to a temperature of 140 degrees F., the temperature 
of the air in the drying chamber ranges from 180 to 200 degrees 
I’. The distance over which the spray falls through the ascend- 
ing current of heated air being sufficient to permit the removal 
from the milk particles of substantially all the remaining 
moisture. 
The Gray Process.—Chester Earl Gray of Eureka, Calif. 
and Aage Jensen of Oakland, Calif.. U. S. patent No. 1,078,848, 
November 18, 1913, Chester Earl Gray, Assignor of one-half to 
Aage Jensen, U. S. patent No. 1,107,784, August 18, 1914, and 
Chester Earl Gray, U.S. patent No. 1,157,935, October 26, 1915, 
and U.S. patent No. 1,266,013, May 14, 1918, subjected the pos- 
sibilities of spray drying to extensive study and invented and 
patented successive improvements and new principles relating 
to desiccation of milk and other liquid substances. 
Gray patent No. 1,107,784 involves an apparatus with a 
circular desiccating chamber A, having a cone-shape lower sec- 
tion DB, terminating in a discharge opening for the dried sub- 
stance, and a discharge opening C for the moisture-laden air. 
The heated air is introduced into the desiccating chamber 
peripherally in a tangential direction, by means of a blower PD. 
Between the blower and the drying chamber there is an inclosed 
heating coil (steam coil) over and around which the air is blown 
into the drying chamber. The tangential entry of the heated air 
into the circular chamber sets up a cyclonic current therein and 
this effect is augmented by introducing the air at several different 
points through tangential openings a. The milk to be desiccated 
enters under pressure through a spray nozzle H, located in the 
