128 SUGAR MILLS. 
struction. I found the yield from the three-roller mills of 
average size and run at a speed of 34 revolutions per 
minute, to be 61 per cent.; whilst from another of very 
large size, of which the rollers were 54 feet in length, and 
28 inches in diameter, and which was run at a speed of 
only 24 revolutions per minute, the yield was 66 per cent., 
the begassa being delivered from the latter almost pulver- 
ized and apparently dry. These results are undoubtedly 
much more satisfactory than would have been afforded some 
years ago; still, they show that after all the care bestowed 
in raising our crops, from one-fourth to one-third of our 
produce is absolutely lost. And if we take what I believe 
to be a fair average of the yield of juice in sugars, that is, 
if we assume that one-tenth of the weight of the juice is 
the product in crystallized sugar, we find that we obtain 
only 64 per cent. of the weight of the cane in sugar, whereas 
chemical analysis shows that it contains 18 per cent.” 
Is there then no means by which the yield of juice may 
be increased? Mr. Benjamin’s experiment indicates a de- 
cided increase by diminishing the speed of the rolls. On 
this subject Prof. R. S. McCulloh makes the following val- 
uable observations,* which are as applicable to sorghum 
manufacturers at the North, as to those for whose benefit 
they were originally intended : 
“During the grinding season, when the chief object of 
many seems to be rather to hurry through with the crop as 
rapidly as possible than to obtain the largest quantity of 
sugar of good quality, the grinding of the cane is often 
performed in a very improper and ineffectual manner. * * 
* * ¥* A general spirit of haste and hurry pervades 
the whole force of the plantation, and in consequence much 
is done without system. In grinding, to obtain the proper 
* McCulloh’s Report, p. 204 
