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BULLETIN 1187, U. S. DEPARTMENT OF AGRICULTURE. 
For the convenience of the miller, a table of equivalents has beeD 
prepared which shows the number of cubic centimeters of water 
to be added to wheats of various moisture contents in tempering 
them to 14 and 15 per cent, respectively. (See reference, Table 1.) 
MILLING EQUIPMENT. 
The experimental mill installed in the laboratory of the Bureau 
of Agricultural Economics consists of two units or mills. (See fig. 10) . 
Each unit consists of four stands of 6 by 6 inch rolls, and one box 
sifter. Three pairs of the rolls of each unit are corrugated and one 
smooth. Each unit is driven by a 5-horsepower motor of 1,150 
revolutions per minute speed. The two sifters, which are mounted 
together, are driven by a 1 -horsepower, slow speed motor. 
Interior of experimental 
The milling equipment also includes a humidifier, by means of 
which the relative numidity of the atmosphere within the mill is 
maintained at not less than 55 per cent. This is done because the 
amount of evaporation of the moisture contained in the wheat is 
affected by differences in relative humidity. 8 Both the relative 
humidity and the temperature of the air within the mill at the time 
of grinding are recorded on the milling record sheet. 
MILLING OPERATION. 
The operation of an experimental mill necessarily differs in some 
respects from that of a commercial mill. In the experimental mill, 
there is no continuous or automatic flow of stock from one machine 
This is an advantage in that it 
to another as in a commercial mill. 
3 United States Department of Agriculture. Bulletin No. 1013: Theinfluenee of relative humidity and 
moisture content of wheat on milling yields and moisture content of flour, by J. H. Shollenberger, 1921. 
