DIFFERENT KINDS OF WILD RUBBER--_continued_
The chief wild-rubber producing countries in the Old World are Africa,
Northern India, and the East Indies.
In Africa, the rubber-giving plants are the _Funtumia elastica_, a
medium-sized tree, and several varieties of vine whose family name
is Landolphia. Both plants flourish in the tropical forests of West
Africa, extending from Soudan to the Congo, and embracing large
areas in Liberia, Gold Coast, Southern Nigeria, and the Cameroons.
Landolphias grow profusely in these same forests, and in the more
northerly West African districts of Senegal, Gambia, and Sierra Leone;
they also abound in British East Africa and neighbouring territory.
Funtumias are tapped on the “herring-bone” system. A native climbs
one of the trees, and as he ascends he makes a wide cut vertically
up the trunk with a somewhat clumsy chisel or gouge; on his downward
journey he makes numerous branch cuts, which run into the central
one alternately on the right and left sides at an angle of about 45
degrees. The milk which comes out of the side cuts trickles down
into the central channel, where it mixes with the milk which is
oozing out therefrom. The whole supply thus finds its way down to a
calabash or pot, which is placed on the ground at the terminus of the
“herring-bone” or “featherstitch” system.
The more destructive method of felling the trees is also adopted by the
collectors of Funtumia milk.
The rubber is prepared from the milk in several ways. The most common
methods are the addition of the juice of another plant, and the burying
of the milk in holes scooped out of the ground. In the latter case, an
oblong hole, 2 to 3 feet deep, is made, and the inside of it is coated
with clay. When the clay is dry, the milk is poured into the hole,
over which is placed a lid of leaves or boughs. Under this treatment,
about six weeks have to elapse before the change called “coagulation”
is brought about, and then the results are far from satisfactory. When,
at last, the hole is uncovered, there is a lump of rubber in place of
the milk, but it usually contains a great deal of uncoagulated and
partially coagulated latex. The lumps are put in the sun to dry, after
which they are taken home to a forest hut. Here they are stored until
such time as some of the natives set forth for the nearest centre of
civilization, to dispose of a stock of rubber to the merchants. The
lumps are carried to town in native-made baskets, which in shape are
rather like the baskets commonly used by us for soiled linen.
The product prepared from Funtumia milk is generally known as “Lagos
silk rubber.”
Landolphias are large vines, which often creep up to the tops of the
highest trees in the forest. They have stout stems which twist and
turn, interlace and knot themselves together into a tangled mass. They
are among the most picturesque of forest plants, for not only have they
the habit of climbing up the trees and intermingling with the branches
in a very decorative manner, but many of them bear beautiful flowers
and brightly coloured fruit.
To tap Landolphias, the natives make cuts in the stems. The milk is
collected and coagulated in numerous ways. Sometimes it is allowed to
flow to the ground, sometimes it is caught in pots or calabashes, which
are hung by a handle on to the stem of the vine, at the spots where the
cuts are made. It may be left to coagulate by itself, or the change may
be brought about by the assistance of heat, or of some plant-juice,
which is known to produce the desired effect. Sometimes a native smears
the milk over his body, and peels off the skin of rubber into which it
is changed by his own warmth.
Some of the Landolphias have underground stems, or “rhizomes,” which,
when pounded, yield “root rubber.”
Landolphia rubber is sent to market in many forms, of various shapes
and sizes. Balls, lumps, biscuits, morsels called “thimbles,” strips,
and twists are some of the commonest forms in which it is exported.
Africa is an important centre of wild rubber supplies from the point of
view of the quantity of the material available in the forests. But the
quality of African rubber is much inferior to that of Para, the rubber
that sets the standard by which all other varieties must expect to be
judged. The inferiority of African rubber is partly due to the milk
from which it is made, but is largely the result of the way in which
the milk is collected and coagulated. The work is all done by natives,
men and women, whose one idea is to get as much rubber as possible in
the easiest way. They are not at all careful to keep the milk free
from dirt and impurities, and there is no science in their method of
coagulating it. However, England, France and Belgium, who between them
own the rubber-producing colonies of Africa, are hoping to improve the
quality of African rubber. You will understand why they are so anxious
to bring about changes for the better in this respect when I tell you
more about the growing popularity of plantation rubber, the rival of
all wild rubber.
There is one kind of rubber plant which all of you must have seen. It
is grown here in pots, and is much used for indoor decoration. Its
botanical name is _Ficus elastica_.
When you see _Ficus elastica_ in its native element, you can hardly
believe that it is exactly the same species of vegetation as the small
“rubber plants” whose acquaintance you have made in many a hall and
drawing-room. At home, on the lower slopes of the mountains of Northern
India--in Darjeeling, Sikkim, Bhotan, Assam, and Burma--and in Java and
Sumatra, it is a big tree, which has very peculiar habits. In the early
years of its life the tree has a single trunk, with numerous branches.
The branches soon begin to let down bush-ropes, which in growing
reach to the ground. Here they enter the soil and take root, and as
these new roots spread, the bush-ropes develop into big trunks. A
well-established Ficus is a most curious sight. It has claimed for its
own an extensive ground space, the whole surface of which is occupied
by exposed roots. Rising from their midst is a crowd of large trunks;
and high and low among the branches are the aerial roots, from which
all but one of the crowd came into existence as bush-ropes.
[Illustration: TAPPING A RUBBER-VINE, BELGIAN CONGO. _Page 39_]
To get at the Ficus milk, the natives hack great pieces out of the
trunks of the trees. Like the Africans, they sacrifice quality to
quantity in their general methods of collecting and preparing their
rubber.
The material made from Ficus milk is commonly known as Assam rubber.
Rubber of various qualities is now made from the latex of the Jelutong
tree. This tree, which is a giant among forest giants, flourishes in
the jungles of Sarawak, Borneo, Sumatra, and Malaya. The tapping of
Jelutong is roughly done by natives, and the milk is coagulated by the
help of petroleum.