MANUFACTURE OF Mik POoWwbER 281 
the drying drums are ineased in a vacuum chamber and the 
drying is accomplished under reduced pressure. Some of the 
U.S. patents of the film-drying process that have found wide 
commercial application are described below. 
The Just Process.—This process appears to be the first of 
its type that found wide application in the desiccating of milk. 
It was invented and patented by John A. Just of Syracuse, New 
York, U. S. patent No. 712,545, November 4, 1902. 
ies 
Fig. 92. The Just milk drier 
The essential equipment involved in the Just process con- 
sists of two horizontal steam-heated revolving metal cylinders. 
hese cylinders are installed sufficiently close to each other so 
that there is contact at their periphery. A milk destributing tank 
(7) with adjustable discharge (8 and 9) in the center over and 
between the two cylinders. Scrapers or knives (11) which re- 
move the dried film of milk from the cylinders: and receptacles 
(12) which receive the finished powder, 
