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proof which became so widely known under his
name. Messrs. Hancock and Macintosh were
in the following year one firm, working at Glasgow
and London, and setting up a factory at
Manchester for the working, by common agreement,
of their patents. More applications of
caoutchouc were devised by Mr. Hancock, who,
among other contrivances, achieved a patent
leather of the solution (instead of the original
cream) pressed into flat fleeces of carded wool,
between two layers of cloth: a tough substance,
much used in machinery. Then, because tailors
discouraged the use of their material, Messrs.
Macintosh and Hancock opened shops for the
sale of ready-made coats, capes, leggings, and
other articles of dress, whereby the use of them
was spread among travellers throughout the
country. Twenty years ago, those old double
fabrics, stiff in winter, and stinking in summer
of turpentine or naphtha, keeping the wet out
and all exhalations of the body infeeling as
if they were truly made of what Indian-rubber
used sometimes to be called, lead-eater, and a lead
-eater that retained all its food upon its stomach
still were in common use, although one
beginning of the end of them had been made ten
years before.

That lesser beginning of their end was made
in Vienna, where the plan was devised of weaving
goods with caoutchouc in the warp or weft.
A thread of Indian-rubber had been made in
'twenty-six or seven by Messrs. Rattier and
Guibal, of St. Denys, by a machine for cutting
spirally a flat-pressed disc got from the bottom
of one of the imported bottle masses. The
process has since been perfected. A strip of
caoutchouc stretched to five times its length,
heated to the temperature of boiling water and
then slowly cooled, does not again contract.
The operation may be six times repeated, and
a strip a foot long may be made to yield, by
this sort of wire-drawing, fifteen thousand six
hundred and twenty-five feet of Indian-rubber
thread. Threads of caoutchouc made somewhat
after this manner were sheathed by a braiding-
machine with thread of silk or other fabric. Sheathed
when at full stretch, and made elastic again by
a hot iron passed over them, they contracted
the surrounding thread into an uniform wrinkling,
and afterwards allowed the play of the
elastic core without breaking the fibres of its
inelastic covering. Such compound thread was
woven into elastic fabrics, first at Vienna, then
in Paris, afterwards in London.

Meanwhile, pump-buckets, engine-hose, buffer-
rings, elastic malting-shoes that would not crush
the grain, caoutchouc corks, were coming into
use, and the Manchester factory of Macintosh
and Hancock produced four thousand square
yards a day of double fabric waterproof cloth.
At last, in the year eighteen 'forty-two, there
began a great revolution in the Indian-rubber
trade.

The natural rubber feels weather to an
inconvenient extent; softens and becomes sticky
under heat, and stiffens under cold. Mr. Good-
year, an American, having supplied by contract
some Indian-rubber mail-bags which he took
to be good and durable, they softened and
decomposed under service, through heat, aided
by some chemical action of their colouring
material. The failure ruined the trade. Mr. Good-
year made some simple experiments of curiosity
on the effect of heat upon the composition that
destroyed his mail-bags, and, accidentally letting
a piece fall on a hot stove, found that instead of
melting, as caoutchouc does at a high temperature,
it charred and hardened. Further experiments
led to the use of sulphur under a certain
heat for making that great and valuable change
in the caoutchouc, now called vulcanisation.
He sent an agent to England with his new
elastic rubber, durable, workable, deprived of its
stickiness, and able to pass unchanged through
all vicissitudes of weather. He desired to sell
his secret. Nobody would buy. But Mr. Hancock,
on seeing Goodyear's material, without
analysis of it, or any unfair dealing, applied his
wits to the discovery of a process that would
effect such a change. He discovered for
himself the sulphur process, to which Mr. Brockedon
gave the name of vulcanisation. It is
effected now in several ways: by rubbing together
caoutchouc softened in naphtha, with ten or
twenty per cent of sulphur, and heating to
three hundred and twenty degrees; by immersing
sheets of Indian-rubber sliced from the
block, for two or three hours in melted sulphur,
at two hundred and forty degrees, and then
heating to three hundred and twenty, when the
change takes place immediately; or by dipping
only for two or three minutes in a certain
chemical tub that contains bisulphide of carbon,
with two and a half per cent of protochloride of
sulphur, and then washing to remove excess of
chlorine. The vulcanised rubber undergoes a
change not at all well understood theoretically
when it is thus made to absorb ten or fifteen per
cent of sulphur, whereof only one or two per
cent is joined to it chemically. The great
practical fact is that it then not only ceases to
be sticky, but remains elastic at all temperatures.

In 'forty-three, Mr. Hancock took out a patent
for his process of vulcanisation. In the year
following, an English patent was also taken out
for Mr. Goodyear, and the two patents were
worked without open dispute until seven years
ago, when an action being brought to try
whether Mr. Hancock had stolen the idea of
Mr. Goodyear, it was proved % that he had not,
though Goodyear's material suggested the
independent investigation towards an achievement
of the same result. To return to the history,
we finish it by adding that in 'forty-five a new
patent was taken out for getting rid of excess
of sulphur by use of a strong hot solution of
sulphate of soda or potash, and since that time
new ways have every year been found of working
and applying the vulcanised material: which
has driven most of the old fabrics out of the
market. Vulcanised in moulds under pressure,
the Indian-rubber becomes hard like ebony, can
be turned in a lathe, and will make combs, cups,