NORTHERN SUGAR INDUSTRY. 



87 



dish were made up to a given volume or weight and subjected to exam- 

 ination. 



The optical analyses were made by double polarization. The chemi- 

 cal analyses were made either by direct titration with Fehling's solu- 

 tion, or by the permanganate method already described. These several 

 methods are designated in the tables by "optical," "copper," or "per- 

 manganate." Where the first has been used with either of the others, it 

 is designated by "optical and reducing." 



In each table the results of the analyses of the chips (or bagasses) are 

 compared with the theoretical composition indicated by the analyses of 

 the juices. Tn this calculation the sorghum-cane is taken at 89 per cent, 

 juice, and 11 per cent, cellulose, &g.; the Louisiana cane at 92 percent, 

 juice, and 8 per cent, cellulose, &c. The percentage of juice to weight 

 of cane expressed from the sorghum canes was nearly 65, and from the 

 Louisiana cane nearly 67. 



The theoretical composition of the bagasse was computed on the basis 

 of these figures. In these compositions it is assumed that the compo- 

 sition of the juice ex})ressed is similar to that remaining in the bagasse, 

 a view which is not opposed by any well verified facts. 



The table ISTo. 2 contains the results of the analyses made as in the 

 first, with the exception that the boiling was continued twice as long. 



In Table Ko. 3 are found the data given by treating the chips with 

 five successive portions of water (each portion somewhat greater than 

 the volume of the chips). After each boiling the water was poured off* 

 and fresh portions added. 



Table ]S"o. 4 differs from the preceding only in having the chips treated 

 with ten portions of water instead of five. In some cases the chips were 

 mashed in a mortar, but this process did not seem to increase the per 

 cent, of sugar extracted. 



Table Ko. 5 contains the results of treating the chips with alcohol 

 instead of water. Both processes were employed Avith alcohol, i. e., boil- 

 ing with a given volume or with successive portions. The determina- 

 tions with alcohol were made by single polarization — alcoholic solutions 

 not lending themselves easily to inversion. The green coloring matter 

 extracted by the alcohol is a serious objection' to its use in extracting 

 sugar from the chips. 



Several experiments were also made to determine the sugar by exhaust- 

 ing the chips with alcohol in an extractor. Both fresh and dried chips 

 were used. With dried chips the process is much more successful than 

 with the fresh. The time employed in extraction varied from one hour 

 to four days. The result of these experiments in varying the time is to 

 show that little advantage accrues from extending the time of extrac- 

 tion beyond two hours. In nearly all cases the fresh chips were 

 thoroughly bruised in a mortar with i)ure sand before being placed in 

 the extraction tube. The mean percentage of sugar as determined by 

 .the extraction of the chips with alcohol was nearly 2 per cent, less 



