CONSTRUCTION AND OPERATION OF CHEESE Factories. 121 
advocated. Since then the system has been put into use and 
is very successful. As one descends into the ground the effect 
of the sun’s heat is left behind. Lower down the internal heat 
is felt, but in a zone said to be between twenty and eighty feet 
below the surface there is a constant temperature of 48° to 50°, 
or possibly colder. This is indicated by the temperature of the 
spring and well water that comes to the surface. By conducting 
air down into the ground and then through a system of tubes 
ten or twelve feet below the surface for a hundred feet or more, 
the air can be carried into the curing room at a temperature of 
not over 60° F. If the curing room is well insulated the air 
‘aa eo 
NORTH 
CURING 
ROOM 
TS 
= SUS -ERRTH DUCT 
Z| 2 __the= 
= 
ci he ai 
ENGINE WORK 
| A 4 Room ROOM 
Fig. 57.—Method of cooling air with cold water. A, curing room; 
B, duct leading into curing room; C, E, galvanized iron drums, air and water 
tight; F, thirteen or more 5-inch flues of galvanized iron, 10 ft. long, soldered 
water tight to drums to cool air; D, main air duct from funnel; G, water 
pipe from pump; H, over-flow pipe; I, damper in main shaft; J, 4-inch pipe 
leading from blower to use when there is no wind; K, smoke stack of 
boiler; L, ventilator from curing room to smoke stack; N, boiler. 
