Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1914-09-29

mated as follows: For 1915, 10000 tons;
1915, 135o0o tons. 1917. $4,000 tons; 1918, 49,
900 tons. This means that in 1918 the
worlds production of rubber Will have
doubled, or more. The resulting effect
on the price of rubber is quite clear as
to the direction of change. The price
may fall to less than 30 cents pound
a change that would be of decided prac-
teal interest to all civilized peoples. In
the midst of an era of steadily rising
general price levels such change would
have a very peculiar interest.
BRAZIL WORKS ON CREDIT.
The superiority of the plantation pro-
duction of rubber seems a very simple
methods are contrasted with the Bra
lillian industry.
In Brazil the whole business is done on
credit, and 1t has so overshadowed all
other use of natural resources in North
ern Brazil that food supplies are eXtrava-
gantly costly. Tie big exporting houses
of Para and of Manaos. halfway up the
Amazon. finance the patron, who has
from two to three hundred natives under
him as rubber gatherers. These gather
ors or "seringuieros," with their fami-
lies and supplies, go Into the forest for
season lasting from May to October, and
establish round of rubber trees, much
as a New England country boy estab-
fishes a round of maple trees in sap time.
hundred and fifty trees are about all
one Gatherer can attend to. The trees
arc considerably scattered, and he has
to cut paths through the brush to con-
meet them.
The trees are tapped by making in
cisions in the outer bark and hanging
small cup below each cut to collect the
"lateX," or liquid rubber. The "lateN" is
not the sap of the tree, but a different
product formed in the outer bark, and
containing a varying percentage of vcge-
table resin. In best Para rubber this
resin is about one-half of one per cent;
while I'm some other wild rubbers il may
reach so per cent. ut Is interesting TO
note I'm passing, that the presence OF
some vegetable resin In natural rubbcrs
has furnished a check on the many al
Legged synthetic" rubbels. In the numer-
GUS synthetic" rubbers produced by Eng
IiSh cXporimenters Il Is said that Ameri-
can chemical analysis has always de-
tpcted the presence of a vegetable resin
this fact strongly suggesting that the
synthetic" rubber contained at least
some natural rubber) In collecting the
lateX from tho rubber tree-the best Para
comes from the hevea-the inclusion of
sap is avoided as far as possible, since 1t
simply adds undesirable moisture; some
does creep in,
The gathered lateX is coagulated and
hardened by a slow and iaborious process
The seringuiero dips a wooden paddle into
the latex and then holds this over a fire
OF special materials, the smoke from
which cUaEulates the rubber. Then he
makes another dip, and coagulates the
second coating of lateX, and so on and so
on until he has built up a big ball or
biscuit of rubber that may weigh all
the way from to 30 pounds, Many OF us
have stopped to gaze at these rubber
balls split open, and displayed 10 urban
curiosity In store windows.
THE PLANTATION RUBBER.
quite different is the story OF planta-
tion rubber. The trees are planted near
together and while the rubber trees are
growing to producing size other and
Quicker-growins trees. mainly palms, are
planted among them, 10 be cut out
when the rubber trees begin 10 produce
later and to need more room for growth.
Cheap and efficient COOlie labor is EN-
plOyed, and II does not have to drag
families and supplies into a wilderness
and there chop lanes in tropical un-
dorrrow-h 70 tind the trees. The trees
are right there near together, The lateX
as it is collected, is poured into squarish
metal boxes, perhaps a foot square, and
cOagulated with acetic acid, the lateX
finally accommodating as a hardened cake
some three or four inches thick, at the
bottom of the pan.
In this form the coaFulated rubber Is
taken through the mills where il Is
heated, passed between corrugated rollers
which reduce ii TO a thinnish, porous
sheet and washed with a stream Of wa
ter The washing takes out practically
an the dirt The resulting sheet, which
may be as much as foot wide and two
or three feet long Is called crepe" be-
cause II has the familiar wTinkled and
somewhat porous appearance that We as
sociate with that word. The crepe may
be also hardened 10 some extent by
smoking.
A more advanced form is the smoked
sheets which are made from the crepe
by special smoking 10 secure greater
hardening and by further rolling The
smoked sheets come 10 the market. here
in the United States. for instance. in
small sheets varying from a sixteenth to
an eighth OF an inch in thickness. The
color, when the sheet is held up to tho
light is Of various shades Of rather deep,
reddish amber. Each plantation has its
own Individual pattern in the corruga-
tions OF the rollers, which form the
smoked sheets. Most of the sheets come
indented with patterns OF diamond
shaped indentations.
There are all sorts Of variations in the
form of the separate indentations. and va
rlations In the angles Of the cTiss-sSQss