The Ely miner. [volume] (Ely, Minn.) 1895-1986, 1909-04-30
THE ROMANCE OF RUBBER

Next to copper and iron, rubber Is
the most important material In the
eiectflcal industry. 1t is used extern
slVely as an insulating material, be-
ing one Of the best insulators Of cleo
trlclty in the world. Nearly all the
wires that carry electrical current are
protected with rubber insulation. Rub
per prevents the electricity escaping
through contact of the wire with other
cenuuctors, it prevents accidents, fires,
and keeps the electrical apparatus from
burning out and destroying itself. Be-
sides being used for insulating wires
and cables at the plants of the Cen
eral Electric company rubber is used
IN the manufacture of motors, switch
es, generators, and nearly all electrical
machines.
The story of rubber is the story Of
the conquest of the tropical jungles;
the fights against disease, poisonous
reptiles and insects, man eating ami
mails, hunger and thirst and the danger
Of being lost forever
Civilization first heard of rubber in
Herreras account of the second voy-
age of Columbus in the year 1493.
where he speaks of elastic balls made
by the natives from the gum of a
tree.
The first authentic account of it's
practical use was recorded in 1745 by
the leader of a French governmental
expedition returning from South
America who reported that the natives
secured from the juice of a tree a GER
tain gum which was very elastic, inl-
pervlous to water and used in making
bottles, shoes and squirt guns.
Thirty years later it was introduced
10 commerce when an Englishman
brought from Assam, India, soft
spongy substance which would erase
lead pencil marks and which after
wards became known as India rubber.
Many primitive uses were found for
this wonderful gum, but owing to it's
susceptibility to changes of tempera-
ture, which rendered it sticky and more
or less fluid. rubber did not come into
its own until early in the last century.
At that time it was discovered, after
great deal Of experiment, that by
mixing sulphur with crude rubber and
subjecting it to high degree Of heat,
these former deficiencies were elini-
mated and a material was produced
which was both tough and elastic, and
would retain those properties under
varying temperatures. This process OF
curing was called INFLAMMATION, and
is the basis of rubber making today.
So great has been the development
of rubber manufacture since that time
that it's products now avceed a va1uo
of $500,000,000 annually.
Contrary to the popular impressions
rubber gum Is not derived from the
sap. It is secured from a milky juice
or latex which is found only in the
bark. This latex contains substances
known as caoutchouc (the active prin-
ciple Of RUBBER, together with certain
a1buminoids, resins, ETC., which upon
the evaporation Of moisture coagulate,
forming a thick, spongy substance.
The percentage Of caoutchouc, IN pro-
portion to other ingredients contained
in the latex, determines the quality OF
the rubber.
The regions from which rubber gum
is secured form an irregular belt in the
tropics and subtropics extending
around the earth, the quality procured
cies of plant, the soil and the climate.
Great quantities are produced in
Africa, Mexico, Ceylon and the Malay
islands, but the most desirable rubber
for resiliency and wear resistance is
secured from a tree found in the ANA
zon river district, South America This
rubber is known as Para, the name be-
ing derived from its chief city Of ex-
port. 1t not only contains as high as
95 per cent of caoutchouc, but the
methods used by the natives In pre-
pairing it for market are so much SUI
perior that it is selected in preference
to all others for manufacturing pur-
poses.
Rubber gathering in the Amazon
River district is hazardous
asd difficult undertaking. The
supply comes from wild trees
scattered throughout dense for
ests, to which paths must be cut
through the tangled and luXuriant I'M
dergrowth. Even then, the trees can
only be reached during three to five
months of the year, as throughout the
wet season the forests are completely
inundated The climate is SO unhealthy
that white men cannot do this work
and it is necessary to rely upon the
native blacks, who at best are unde-
pendable and lazy. Their reluctance to
join rubber gathering expeditions can
readily be understood when it is re-
membered that out of a seasons ex-
petition perhaps only half will return
alive.
When rubber tree is found the nat
i've gatherer cuts a series Of gasheS
into the bark with his machete, encirc-
ling the tree from the ground UP, as
high as he can reach. Cups are fas-
tened to catch the latex as it oozes out.
When a sufficient quantity is collected
it is removed to the temporary hut
where dense smoke producing fire is
made Of certain nuts and palm leaves.
Then taking his wooden paddle the ma
tive dips it into the latex and holds 1t
over the fire, turning it round and
round until the latex coagulates. AS
soon as it is hard a new layer of
latex is added and coagulated as be-
fore. This process is continued until
the mass has grown too large for han
ding, when the paddle is taken out
and the rubber set aside for export.
The process of coagulation and fumi-
cation with these specially selected
nuts and leaves prevents decay and
adds to the life and wear resistance Of
the manufactured product.
Tapping the trees for rubber does
not necessarily destroy them. nor is it
believed to materially shorten their
life; but unfortunately many thou
sands Of trees are annually rendered
useless by careless and improper meth
DDS Although the source of crude rub
Der gum is practically inexhaustible,
the limited native labor supply and the
difficulties encountered up to the time
of marketing 1t have tended to keep
down the supply and maintain high
standard of prices.
How Russell Sage Made Money.