10 



The principle of the method practiced by the Department rests on a 

 different basis from that described by Gilbee. The chief object of the 

 method of Gilbee is to get rid of the alkaline salts of beet syrup, while 

 the object of the experiments carried on by us was to separate the un- 

 crystallizable carbohydrates. While the method of Gilbee embodies 

 the main process of our method, it is seen without discussion that it 

 could not be applied economically. 



It is but just to say that our method was developed, perfected, and 

 carried out in its experimental work before our attention was called to 

 patent of Gilbee in March, 1892, by Prof. 0. A. O. Eosell, of the Patent 

 Office. 



The use of alcohol for precipitating gums for chemical purposes has 

 long been practiced. Its application to sorghum molasses for this pur- 

 pose is described by Dr. Peter Collier and Mr. Clifford Eichardson in 

 the Annual Eeport of the Department of Agriculture for 1878, page 107. 



ABSTRACT OF METHOD USED IN EXPERIMENTAL WORK. 



The process of manufacturing sugar from sorghum by the alcohol 

 process, as carried on by the Department in its experimental factory at 

 Medicine Lodge, may be briefly described as follows : 



The cane when brought from the field is passed through a cutting appa- 

 ratus and cut into pieces about 1 inch in length. These pieces of canes, 

 together with the short pieces of blades, are next carried to a fanning 

 machine, by which the blades and other light particles are entirely re- 

 moved. The clean pieces of canes are next conducted to a shredding 

 machine, in which they are torn into as small bits as possible, the finer 

 the better. The pulp thus prepared is elevated above the center of the 

 diffusion battery, whence it is conducted into the cells of the battery by 

 a swinging funnel. The diffusion juices are collected into clarifying 

 tanks, neutralized with lime, the temperature raised to the boiling 

 point and the skimmings removed in the usual way. The clarified juices 

 are then left to stand in the clarifying tanks until the sediment has fully 

 settled when the clear juice is drawn off and sent to the multiple-effect 

 evaporating apparatus. The sediments are collected in a separate tank 

 and reclarified, being either rejected, passed through a filter press or 

 returned to the cells of the battery. 



In the multiple effect the sugar juices are concentrated to a sirup 

 containing about 55 per cent of solid matter. This sirup is then con- 

 veyed to tall cylindrical tanks, each one being filled to little less than 

 half its depth. An equal volume of 90 per cent alcohol is then added 

 and the whole thoroughly stirred together by blowing cold air in at the 

 bottom of the tank. As soon as the sirup and alcohol are thoroughly 

 mixed the impurities of the sirup are precipitated in flocculent masses. 

 The whole is then allowed to stand for a few hours, if time permits for 

 twenty-four hours, when it is found that the precipitated matters have 

 settled nicely to the bottom of the tank, leaving a clear alcoholic sirup 



