ON THE JUICE OF THE SUGAR-CANE. 343 
What is very remarkable, the juice in this state may be kept for 
nearly twenty-four hours in conditions of temperature most favourable 
to fermentation without showing the slightest change indicating such an 
action ; but after this period it becomes dim, and corpuscles are 
developed in its thickness ; fermentation then sets in, and continues 
slowly, and it is only at the end of two days and at a temperature of 25° 
centigrade that well-formed bubbles appear in the liquid. 
When the juice has been simply cleared from the fragments of vege- 
table matter, which it always carries down with it, fermentation on the 
contrary is rapidly produced after its extraction from the cane, and in a 
few hours the liquid becomes viscid. In the latter case, fermentation is 
almost complete, though it has not even commenced in the juice, the 
separation of the globules of which has been effected in the manner 
mentioned above. This granular matter then plays an important 
part in the fermentation of the juice, and should be regarded as the 
principal agent of that change which takes place in this liquid during 
the first twenty-four hours nearly which follow its extraction from the 
cane. 
Cane juice at the boiling point becomes freed from the albuminous 
substance which it contains, and this substance, coagulating under the 
influence of heat seizes on the globular matter which it draws into the 
flakes which form on the surface of the liquid. This albumen of the 
cane juice has also great importance as an exciting cause of fermentation, 
for to its agency must entirely be attributed that change in the juice 
which, after boiling, has been completely freed from its albumen and 
its globules by means of filtration, may be kept perfectly fresh for two 
days at least, at a temperature of 30° centrigade. At the end of this period, 
a thin pellicle is seen extending along its thickness, and on the next 
day a slight cream-like appearance covers its surface, while at the same 
time the colour has changed ; but it is only at the end of the third day 
that fermentation positively shows itself. 
To resume, the juice filtered through a cloth and left to settle, 
becomes a liquid more or less of a disturbed and milky appearance, and 
of a yellowish green colour which is of a deeper hue in proportion as 
the cane is riper, and of a deeper tint, whether the plant be the striped 
or smooth species. In its normal state and after deducting the effect of 
the remains of the tissues, which are accidental and easily removed, this 
juice is composed of a solid granular portion and of a liquid holding in 
solution a certain number of organic and mineral substances. This solid 
portion consists of globules or organised bodies suspended through the 
entire extent of the liquid, and which differ essentially from the other 
vegetable principles contained in the cane-juice. These globules which, 
in their living state, without doubt possess special physiological qualities, 
are beyond all other substances contained in the cane, those 
which possess in the highest degree the power of exciting alcoholic 
fermentation, Its action would appear to begin with the remission of 
vol. vi. N N 
