me dried gum and one tree I had tapped in this way* 
yielded me 50 lbs. Even by this method however, less- 
than one half of the juice is saved as it is impossible 
to tap the small branches &c. However by stripping 
the bark from the branches and submitting it to pressure 
between rollers we can obtain almost the entire amount. 
The juice obtained by pressure is much less pure than 
that obtained by tapping the tree, on account of the 
large quantity of water and mineral impurities that are 
also expressed from the bark. The juice as it leaves the 
tree contains from 40—50 per cent, of water, and the 
problem is how to get. rid of thi3 water most readily 
and economically and at the same time to leave the gum 
in a pure condition. The readiest and by far the 
cheapest method is simply to expose the juice to the action 
of the sun, which in a short time, varying with the humi- 
dity of the atmosphere, dries the mass. This however 
is attended with seveial difficulties, first the loss of time 
occupied in the process, (5 days being the shortest 
time that even a thin layer of gum can be dried in the 
dry weather, and in the wet season three and four months 
often elapse before a thin film even appears on the sur- 
face). The action of the atmospheric oxygen however 
during this process is so great that a quantity of either the 
gum itself or some of the other juices of the tree become 
o^ydized, the whole mass becomes strongly acid, acquires 
the same smell as stale juice and what is worse than all 
becomes of a dirty brown colour, which is very difficult to 
remove. Another method which certainly has neither of 
the deficiencies of the former one is to act upon the 
juice with strong alcohol. By this means it is immedi- 
ately coagulated, a large portion of the alcohol seeming to 
