1 June, 1898. ] QUEENSLAND AGRICULTURAL JOURNAL. 481 
RUBBER MANUFACTURE BY SOUTH AMERICAN NATIVES. 
Tose concerned in the caoutchoue or rubber industry will be interested to 
learn that certain South American natives have long made a practice of water- 
proofing blankets and of making waterproof garments and bags by a process 
which originated among themselves, and which was not the result of contact 
with white men. From the Indiarubber World (New York) we take the 
following account of the process adopted by these Indians, supplied to that 
journal by a Cuban gentleman, a civil engineer by profession, who has seen 
much of Colombia. Other extracts from the same journal follow :— 
While engaged in some professional work, with a view to reporting on 
the feasibility of building a railway on the Pacific side of the region of Darien, 
which forms the south-eastern portion of the Isthmus of Panama, in the, 
Republic of Colombia, the writer had occasion to make some observations on 
the rubber industry in that part of South America. That country being little, 
known, the work of exploration took « large share of our time, and as we 
advanced through the virgin forest hardly a day passed without our coming. 
across some rubber-trees. We had little trouble to detect them, because our 
guides and some of the natives that were with our party to cut paths through 
the tropical woods were old rubber-men who had formerly, for many years, 
made a livelihood by selling the rubber which they gathered from the trees, 
for which they were constantly on the look-out. Of late, however, they had 
not been very active in that line, because the destructive practice of cutting 
down the trees instead of simply tapping them to extract the milky juice had 
made it necessary for them to go farther and farther into the forest. 
The practice followed in that region, after felling the tree, is to raise one” 
or both ends a few inches above the ground, allowing them to rest on logs or 
wooden blocks cut out in the neighbourhood. The ground directly under the 
tree is cleared as well as possible, and covered with leaves as large as can be 
procured nearby. Several incisions are then made all around the trunk, and 
at short intervals, somewhat in the form of a spiral. “These incisions are then 
made all round the trunk, and at short intervals, somewhat in the form of a. 
spiral, These incisions are made deep enough to cut through the bark. The 
milky juice oozes out along these incisions, and drops slowly on the top of the 
leaves. These are taken up and emptied into “ calabashes,”’ or more often into 
waterproof bags made by the natives with the aid of their own rubber. In — 
this manner the juice is transported to where it is desired to coagulate it. This 
is often done in the proximity of the fallentrees. A square hole is dug in the 
-ground to receive the juice, which is mixed with a little common washing soap 
which has previously been dissolved in water. ‘This mixture is agitated with 
the hand, and at the end of fifteen or twenty minutes a large portion coagu- 
lates and separates from the liquid in the form of a solid mass. This is taken 
out, and the remaining liquid is again treated with soapwater to make sure 
that all the available rubber has been precipitated. Before the natives learned 
the use of the soap to hasten the process, they had to leave the juice in the. 
hole in the ground for many days before it would coagulate. If the trees are 
tapped instead of felling them, the incisions are made as stated in the previous 
ease, with an additional.one running lengthwise. The leaves are crowded 
around the base of the tree, and the juice drops on them as before. 
Several years ago some of the native rubber-seekers became dissatisfied 
‘with the price they were getting from the merchants to whom they sold their | 
rubber, and they started a systematic way of adulteration, and they did it with 
such art that the impurity could not be detected until the rubber was sub- 
mitted to treatment in the foreign ports to which it was exported. This 
adulteration consisted of mixing with the juice an equal amount of a certain 
kind of clay obtained from the neighbourhood. It nearly doubled the weight 
of the resulting impure rubber, whose appearance did not betray its composi- 
tion, and consequently they got double the price they would have been paid 
for the unmixed rubber, the loss falling on the merchant or manufacturer, 
