50 
BULLETIN 1136, U. S. DEPARTMENT OF AGRICULTURE. 
time it passes through the circuit ; but with the condensers no attempt 
is made to do this, and condenser water just sufficient to keep the 
humidity down to the desired point is used. A kiln designed for the 
use of condensers only, need have neither sprays nor baffles, and the 
height of the condensers may be varied to meet individual require- 
ments. Water-spray and condenser kilns require a supply of cold 
Fig. 8.— Cross section of water-spray compartment kiln. 
water in addition to the steam or other source of heat. In the con- 
denser kiln the water is ordinarily run out as waste after passing 
through the coils, but in the water-spray kiln it is usually returned 
from the spray chambers and recirculated by means of pumps, 
enough cold water being added to bring the temperature down to 
the desired point. The humidity in the water-spray kiln, when using 
the sprays, is controlled by regulating the water temperature; and 
