The Camden chronicle. (Camden, Tenn.) 1890-current, 1904-12-09
ALUMINIUM INDUSTRY.
MANIFOLD USES OF THIS RE-
MARKARLE METAL.

and Cheap.
The history of the metal aluminium
ard it's use in the arts is peculiarly
illustrative of the method Of industrial
development, aided and fostered by
scientific research, says the New YORK
Evening Post. For three-quarters OF
a century the metal was a scientlhc
curiosity, but the appearance OF de-
mand for it resulted in the almost
immediate perfection of methods Tor
it's extraction. whereby it's cost was
SO reduced as to make it available Tor
common uses.
AS long ago as 1907, Sir Humphrey
Davy conjectured the existence of
metallic element as component OF
clays and alumina. In 1928 German
chemist, Wohler, actually separated
the metal from its compounds, and
discovered its remarkable physical
properties of lightness, toughness and
ductility But for more than 60 years
no use was found for aluminium, be-
yond an occasional employment OF
very small quantities in the construc-
ton of scientific apparatus. At the
centennial exposition in 1876 sur
veyor's transit made of aluminium was
exhibited, but it's remarkable lightness
was even less astonishing than the
value placed upon it-aluminum was
then about six times as expensive as
silver.
Naturally, in the progress of engi-
neering and invention that distin-
guished the last quarter of the 18th
century, the attention of inventors and
constructors was attracted to the new
metal, and it was freely predicted that
much use would be made of it, if its
cost could be reduced so that it might
compete with cheaper materials OF
struction. Weighing only about one
third as much as an equal bulk OF
brass or copper, it resists most acids,
has white lustre, is an excellent con-
ductor of electricity, and is possessed
of many other desirable qualities.
Here, then, was the incentive to in
ventors, and many chemists set out to
discover method for the economical
extraction of aluminium. Its ores exist
in great abundance, common clay con-
tanning a large proportion of the
metal; but of all substances these
very ores seemed most refractory and
least amenable to chemical treatment.
A number of processes of a purely
chemical nature were devised, but
none of them reduced the cost of pro-
duction to such point that the metal
could compete with steel and brass as
an element of construction.
At last a process was found that is
both simple and cheap, 1t was discov-
cred that cryolite, mineral found in
great quantity in Greenland, and con-
sisting almost wholly of aluminium
fluoride, was easily melted, and. that
in it's fluid state it dissolved crude
alumina as readily as water dissolves
sugar. A powerful current of electric
ity passed through this molten mix
ture was found to extract the metallic
aluminium, and the process was also
seen to be regenerative; that is, the
cryolite is not consumed, put is used
over and over, the molten bath be-
ing supplied from time to time with
crude alumina. This material exists 4
in nature as a mineral, named bauxite,
after the town Les Baux, near Aries,
in the south of France, where deposits
of it are found. Vast beds of it exist
also in Arkansas and elsewhere in this
country
The smelling process is of the sim
plest. In an iron vat, about the size
and shape of an ordinary bath-tub, is
melted charge of cryonre, a gas fur
mace supplying the necessary heat
When the charge is melted, powdered
bauxite is stirred in, and an electric
current is turned on between cast-iron
electrodes immersed in the mixture.
The electric current furnishes enough
heat to keep the mass melted, and the
liquid aluminium collects at the bot
tom of the bath, whence it is tapped off
from time to time. Once started the
process is continuous until the dirt
and impurities collected in the vat re-
quire it to be drained and recharged
Aluminium, extracted by this process
at Niagara Falls, at Kensington, Pa,
at Foyers, in Scotland, and at numer-
Gus establishments on the continent
of Europe, took its place in the arts
Immediately. AS an element of con-
struction, however, it did not meet the
expectations of it's earlier advocates.
1t was found to be difficult to work,
cumming the teeth of files and stoutly
resisting cutting and drilling tools on
account of its toughness. But new
rrcac of O,oo davoIOnaJ Tho Norxoon