12 QUICK METHOD FOR DETERMINING MOISTURE IN GRAIN. 



light material, preferably aluminum, a scoop of this kind need- not 

 ^veigli more than 50 or 75 grams and can be substituted for one of 

 . the scale pans or used with a counterpoise. The scoop should be 

 about 4 inches wide. 



GRINDING THE GRAIN UNNECESSARY. 



The whole kernels are used for making the moisture determination, 

 thus doing away with the preliminary grinding of the samples; in 

 fact, the method described is not applicable, without some modifica- 

 tion, to samples of ground grain. Ground samples have a tendency 

 to cake in the bottom of the flask and prevent a free circulation of 

 the oil. with a corresponding variation in the temperature at different 

 points in the sample of meal, and the results obtained are not reliable. 

 Moreover, the grinding of samples for the determination of moisture 

 in commercial o-rain is alwavs to be avoided. Grain of this character 

 generally contains a high percentage of moisture, and with the 

 " burr " type of mill usually used for grinding samples of this 

 kind the friction developed during the grinding causes a rise in 

 temperature and a corresponding loss of moisture. This loss of 

 moisture increases as the water content of the grain increases, and 

 in samples of grain which have begun to sweat this loss is frequently 

 as much as 1^ per cent. 



OIL FOR THE MOISTURE TEST. 



QUALITY REQUIRED. 



In securing an oil suitable for the bath in which the corn is to be 

 heated, five primarj^ factors must be taken into consideration : 



(1) The oil must be free from water. 



(2) It must be an oil having a comparatively low viscosity, so 

 that it will run freely at ordinary room temperature. 



(3)' The flash point must be sufficiently high to avoid danger of 

 an explosion or fire. 



(4) The saponification value should be zero. 



(5) The oil must be cheap. 



Experiments have demonstrated that any of the pure hydrocarbon 

 oils showing a composition within the range of the tAvo samples in- 

 dicated below will give satisfactory results : 



No. 1. No. 2. 



Specific gravity at 15.5° C 0.9005 0. S0.57 



Viscosity at 20° C. (Engler) 19.2 6.2 



Flash point (open cup) degrees centigrade-- 205 175 



Fire point (open cup) do 245 210 



Saponification value None. None. 



An oil similar to sample Xo. 1 is to be preferred to sample No. 2, 

 owing to the difference in the flash point, altho the latter may be 



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