CITY MILK AND ICE CREAM PLANTS 321 
use clarifiers, but those who do, claim that the clarific- 
tion of milk is a paying proposition. So long as milk is 
not produced under the sanitary conditions which now 
‘prevail upon certified dairy farms, just so loug will clari- 
fication remain a desirable practice. 
The plans submitted provide for pasteurization by the 
held or retarder process. When the heating is finished 
the milk is discharged over a large cooler of the tubular 
style which is most commonly used in milk plants. 
It will be noted that the plan provides for a room de- 
voted exclusively for making butter, ice cream, cultured 
milk, fancy cheese and modified milk, all of which can 
be profitably undertaken by milk dealers, and sufficient 
room should be provided to allow for expansion in these 
side lines. 
One common mistake in milk plants is the failure to 
isolate the wash room. This is a very essential matter 
because milk is certain to become contaminated when the 
washing is done in the same room in which it is pasteur- 
ized or bottled. 
The illustration shows the use of steam only as a source 
of power. In some of the larger plants, however, the 
machinery is run with gas power, which is far more 
economical than steam. It is estimated that a pound of 
coal burned in a gas producer will develop about eight 
times as much power as the same amount of coal burned 
under the boiler. 
In a large and expensive milk plant recently con- 
structed the gravity system of handling milk is used dif- 
ferently from that shown in the foregoing illustration. 
The different machines are elevated one above the other 
by a series of platforms arranged between the floor and 
the ceiling. Necessarily the ceiling is a considerable dis- 
