25 



alysis No. !;"> was made a day after tlie tires in the furnaces had been 

 stopped. It showed that when internal combustion alone was practiced 

 the percentage of CO 2 rapidly decreased. A gas containing from 20 to 

 IT) per cent. (JO., is well suited to carbonatation. 



VOLUME OF GAS EMPLOYED. 



The double-acting pump for supplying gas to the pans had the fol- 

 lowing capacity: 



Inches. 



Diameter of cylinder 17.5 



Length of stroke 21.25 



The mean rate of motion for the pump was 40 per minute ; hence the 

 total quantity of gas delivered per minute was 236 cubic feet. 



The volume of CO 2 furnished per minute is obtained by multiplying 

 the above number by the mean percentage of CO 2 in. the gas, viz, 236 

 X .20 = 47.2 cubic feet. 



In metric terms 47.2 cubic feet are equal to 1 ,336 liters. 



With gas of a good quality, say 25 per cent. CO 2 , a pump of the ca- 

 pacity described would easily furnish gas for working 200 tons of cane 

 per day. 



DOUBLE CARBONATATION. 



A few experiments were made to determine whether or not double 

 carbonatations could be practiced with sorghum juices. 



It was found that if from two to four tenths grams of lime per liter 

 were left in the juice of the first carbonatatiou the filtration took place 

 more readily, and the juice was somewhat purer. 



In double carbouatation some additional lime is added to the hot 

 juice from the filter-presses, and the injection of CO 2 continued until 

 the liquid is neutral. Pans were put up and this method given a trial. 

 But with a sugar-juice as rich in glucose as that afforded by sorghum, 

 this procedure is not applicable. 



For convenience, and to note the effects of a heavy frost, the analytical 

 data relating to the juices, &c., are given in two parts, viz, those obtained 

 before October 1 in the first part, and those after September 30 in the 

 second. It is believed that every analysis made has been recorded, since 

 in the circumstances arising from the result of the experiments even 

 those which seem to have no value have been considered worthy of 

 finding a place. 



MILL-JUICES. 



The samples of cane expressed by the small mill were taken without 

 any purpose of illustrating any theory. The object in selecting them 

 was to get as fair an idea as possible of the character of the cane enter- 

 ing the factory. 



A study of the tables reveals the most surprising variations in the 

 composition of the canes, varying from a quality of high sugar-produc- 

 ing value to one worthless for this purpose. 



As has already been pointed out, the generally poor character of the 



