35 



Throughout the operatioii the temperature is kept as near the boil- 

 ing point as can be done conveniently without danger of filling some of 

 the battery cells with steam. Diffusion takes place more rapidly at 

 high than at low temperatures, and the danger of fermentation, with 

 the consequent loss of sugar, is avoided. The process will be readily 

 understood from the above diagram, in. which the columns represent 

 the cells of the battery, the numbers at the left the number of diffusions ; 

 iv, water; J, liquid in the cells, or passing through them, and J, juice to 

 be drawn. 



INVERSION OP SUGAR IN THE DIFFUSION CELLS. 



In the experiments at Fort Scott in 1886 much difficulty was experi- 

 enced on account of inversion of the sugar in the diffusion battery. The 

 report shows that this resulted from the use of soured cane and from 

 delays in the operation of the battery on account of the imperfect work- 

 ing of the cutting and elevating machinery, much of which was then 

 experimental. Under the circumstances, however, it became a matter 

 of the gravest importance to find a method of preventing this inversion 

 without in any manner interfering with the other processes. On the 

 suggestion of Professor Swenson a portion of freshly precipitated car- 

 bonate of lime was placed with the chips in each cell. In the case of 

 soured cane this took up the acid which otherwise produced inversion. 

 In case no harmful acids were present this chalk was entirely inactive. 

 Soured canes are not desirable to work under any circumstances, and 

 should be rejected by the chemist and not allowed to enter the factory. 

 So, also, delays on account of imperfect machinery are disastrous to 

 profitable manufacturing and must be avoided, But for those who 4e,< 



