Report of Society's Meetings. 175 
see what the waste of fuel amounts to in pounds of coal per ton of 
sugar by burning green megass. ioo ffis. of canes, with an extraction 
of 70 0/0, yield 70 lbs of Juice. 70 lbs. juice,=6'6 gallons x 1.6 lbs. of 
sugar per gallon = io"5 lbs. of sugar. 70 0/0 of I0'5 = 7'3 lbs. of 
sugar obtained from 100 lbs of canes. - a a * ° x 100 = 30695 lbs. of canes 
required to make one ton of sugar. 30695 lbs. of canes give 9208^5 lbs. 
of megass and as we have seen before, 100 lbs. of megass of 70 0/0 
crushing, when dried in the logie, loses 14/4 lbs. of water more, than 
would have been evaporated by the decomposed sugar, if the megass 
was burnt in its green state. 9208*5 x \^£ = 1326 B3s. of water. 13 6 tB 
= 221 lbs. of coal lost per ton of sugar, by burning the megass, as it 
leaves the mill. 6 R>s. of water per pound of coal is about the average 
duty of boilers in this colony. This low figure is chiefly due to the 
unskilled attendants we are obliged to employ. For 75 0/0 crushing 
we obtain from 100 lbs. canes 7 galls, of juice x v6 = ll"2 ft>s. of sugar. 
70 0/0 of u - 2=7 , 8. •L 2 -i5x 100 = 28718 lbs. of cane necessary to 
make one ton of sugar. 28718 x o'25 = 7180 lbs. of megass, giving 
a. loss of 7180 x T %\> = 653 lbs. of water, x -f- 5 - = 109 lbs. of coal lost 
per ton of sugar. In a similar way, we find that the loss of coal per ton 
of sugar when the crushing is 65 0/0 amounts to 382 lbs. In these 
examples it is assumed that the sugar obtained from the juice equals 
70 0/0 of the indicated sugar. When the manufacture is better than 
that, the waste of coal is of course less. The last line of the table gives 
the number of pounds of feed-water, which can be evaporated by 100 
lbs. of megass. From this it will be seen, that a given weight of 70 0/0 
crushing megass can evaporate almost twice the feed-water, that can be 
evaporated by the same weight of 60 0/0 crushing megass, also that 100 
lbs. of megass of 30 0/0 crushing contain three pounds of water more 
than can be evaporated by the carbon present in the megass. The figures 
preceded by the minus sign indicate the excess of water in the megass 
over that, wbich can be evaporated by the available carbon. When the 
crushing is 60 0/0, the amount of feed-water evaporated becomes very 
small and the megass does not burn well. When it falls much below 
60 0/0, the megass simply smoulders and the fire finally goes out. 
In order to make some of the foregoing appear more comprehen- 
sively, the following synopsis is given. 
The useful carbon available in sugar equals about 37*3 0/0 of the 
weight of the sugar. 
It is w*ong to compare green megass with coal, by taking the total 
