48 
The trees are tapped in the evening, and the juice is collected on tho 
following morning. Yo obtain the juice, « deep horizontal incision is made neay 
the base of the tree, and thence a vertical cut extends up the trunk, with others 
at short distances in an oblique direction. Small shallow cups made from the 
clayey soil and dried in the sun are then placed below the incisions to receive 
the milk, each cup being attached by sticking a small piece of clay to the trea 
and pressing the cup against it. The juice each tree yields is about 6 oz. 1 
three days. It has a strong ammoniacal odour, which rapidly goes off, and in 
consequence of the loss of ammonia it will not keep Jonger than a day 
unchanged; hence when it has to be carried to 4 distance from the place of 
collection, 8 per cent. of liquid ammonia is added. The juice is said by Bruce 
Marren to yield half its weight of caoutchouc, but 80 per cent. appears to be 
the usual quantity. ‘To obtain the rubber the juice is heated in the following 
manner :—A piece of wood about 8 feet long, with a flattened clayey mould at 
one end of it, is dipped in the milk, or the latter is poured over it as evenly as 
possible. The milk is then carefully dried by turning the mould round and round 
in a white vapour obtained by heating certain oily palm-nuts (those of Attalee 
excelsa being much preferred), the vapour being confined within certain limits 
by the narrowness of the neck of the pot in which the nuts are heated. Each 
layer of rubber is allowed to become firm before adding another. A practical 
hand can make 5 or 6 Ib. inan hour. From whatever cause, the rubber thus 
prepared is the finest that can be obtained. ‘The flat rounded cakes made in 
this manner are known in the London market as “ Biscuits.” 
(Lo be continued.) 
