THE BROWN-DUVEL MOISTURE TESTER 
17 
HOW TO MAKE A MOISTURE TEST 
The method of making moisture tests with a Brown-Duvel tester 
consists of heating the whole kernels of the various grains, rice, seeds, 
spices, or the flour, meal, broken grains, or other material to be tested 
in a mineral oil having a flashing point much above the boiling point 
of water, in condensing the water which distills off, and in collecting 
and measuring the moisture in a suitable graduate. The method is 
so simple that the tests can be made by any careful worker who is 
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Fig. 16. — Balance for weighing samples to be tested for moisture content 
able to follow simple instructions, but it is essential for uniformly 
accurate results that the tests be made in strict accordance with the 
details of the method here described. 
After properly mixing the bulk sample to be tested, carefully weigh 
the desired quantity for the moisture test and empty immediately 
into the distillation flask, to which add the oil and then shake, with a 
slight whirling motion, until the two become well mixed. Grasp the 
neck of the flask in one hand and hold it in such a manner that when 
the No. 5 rubber stopper carrying the thermometer is inserted it can 
be readily determined that the mercury bulk of the thermometer is 
60637°— 26 3 
