REPORT OF THE CHEMIST. 



43 



September, 1S83. According to the observations of Iviffard on tropical 

 cane, the mean content of sugar is 15.3 per cent, in the juice, or 13.77 

 per cent, of the total weight of cane. There is expressed by doable 

 milling with intermediate saturation of the first bagasse with hot water 

 an amount of saccharine matter represented by the following figures : 



Per cent, juice expressed by first mill 00 



Per cent, juice expressed by second mill 25 



equal to 11 per cent, of normal juice. Total per cent, normal jnice ex- 

 pressed, 71. Each 100 kilograms of cane, therefore, furnished 71 kilo- 

 grams of juice, or Zl^^!?= 10.80 kilograms of sugar. But 100 kilo- 

 grams of cane contain ^^L -li- =13.77 kilograms of sugar. The 



sugar lost in bagasse, therefore, is 13.77—10.80=2.91 kilograms. 



The total amount of sugar lost in the molasses is .75 kilogram ; and 

 in manufacture, .86 kilogram ; and total sugar obtained, 9.25 kilo- 

 grams. 



This is certainly a favorable showing for mill work, and yet these are 

 the results which led Riffard to make the experiments with diffusion. 



In sorghum the best yields of sugar heretofore obtained on weight of 

 cane have been 3 to 3.5 per cent. We would certainly be satisfied if 

 this could be raised to 9.25. 



DIFFUSION OF THE BAGASSE. 



Kiffard made some experiments with the bagasse, although I think it 

 hardly proper to call them experiments with diffusion. When the cells 

 are crushed, as in the bagasse, maceration is a more appropriate term. 

 The bagasse was chopped in a straw-cutter and placed in diffusion- 

 cells holding 73 kilograms each. In all, 950 kilograms were used. The 

 amount of diffusion juice obtained was 3.8 hectoliters ; of wash water, 

 5.4 hectoliters. Reduced to the basis of the density of the juice as it 

 comes from the mill, this gave 53.93 per cent, of the weight of the ba- 

 gasse, or 21.57 per cent, of the weight of the cane. It is thus seen that 

 by double milling 71 per cent, of juice is obtained, and 21.57 by diffusion 

 of the bagasse, giving a total content of 92.57 per cent, of juice in the 

 cane. 



The following is the summary of the experiments made with bagasse: 



1. The bagasse must be cut into small pieces before it is subjected to 

 diffusion. 



2. In this condition the bagasse readily submits to the process. 



3. The products of diffusion calculated as normal mill juice amount 

 to about 22 per cent, of the weight of the cane. 



4. With rapid work the purity of the juice will be equal, if not supe- 

 rior, to that of the second milling. 



5. The system of the " long battery" is the one to be adopted. 

 These are valuable results. They show that it would pay to institute 



the process of diffusion in connection with milling. 



One of the great objections to the introduction of diffusion has always 

 been that it would result in the practical loss of the milling machinery 

 already in operation. But from these experiments it appears that the 

 process can be established in connection with milling, and then when 

 the mills break or wear out the diffusion machinery will be ready to 

 take their place. 



