The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1900-12-09
NEW HEAT PRODUCER.
Extreme High temperature Produced
by a Novel m Reaction.

New York Evening Post.
Electrical engineers in this city are much
interested in a remarkable chemical reac-
ton recently discovered by DR.. H. Gold
schmidt, Of Essen, Germany, which makes
it possible to bottle up" and store away
in concentrated form the heat energy of a
large electrical plant. Fully 5000 degrees
centigrade (about 800 degrees FahrenheiD
is the temperature of the hottest portion
of the electric arc. This is such an ex-
cessive heat that it is difficult to realize
it's intensity. 1t is over seventeen times
as hot as boiling water, nearly four times
as hot as melted copper and about twice
as hot as melted platinum. the most re-
fractory of the common metals. At this
temperature steel is a thin and mobile
liquid which behaves much like water, and
the diamond melts away like ice in a gas
flame. And yet this enormous temperature
may be obtained, 1T seems, by the simple
combustion OF a metal in the presence Of
iron rust and metallic superoxide.
Previous to DIR. G~oldschmidt'S discovery
this degree Of heat had not been CONNER
cially obtainable in any other way than by
the use of the electric furnace, such as the
great one at Niagara Falls, and hence its
use has been more or less limited by the
necessity for an electrical generating sta
ton and a considerable amount Of special
apparatus. The new furnace depends on
the enormous heat generated by the com
buStlOn OF powdered aluminium. The great
reducing power of this metal, that is, it's
ability TO take oxygen away from other
substances, has, of course, been known for
many years, and indeed would have been
expected from the tenacity with which it
holds on TO the oxygen when it has once
gathered it in, requiring as 1T does the
heat of the electric furnace to loosen it's
grip, as in the X process of sep
arating the pure metal from common clay,
which is an oxide of aluminium. Into the
aluminium furnace, whose walls must be
lined with some very refractory substance
and well insulated, ground aluminium is
introduced and well mixed with some me-
tallic oxide, iron oxide, for instance Gron
rust.) Then there is added e small guam
tity of a superoxide CDR. Goldschmidt has
used barium peroxide) for the purpose OF
starting the oxidation of the aluminium at
a low temperature. The barium peroxide
is ignited by means of a magnesium ribbon
or powdered magnesium. the substance
ordinarily used for making flashlight photo
graphs. The magnesium is simply lighted
with a match and thrown into the fur
mace. The aluminium mixture begins to
burn fiercely and soon changes into a liquid
mass consisting of two layers-at the bot
tom molten iron covered by a scum of
aluminium oxide. The temperature soon
reaction is so binding that the use of dark
ened glasses is necessary. The Stag OF
aluminium oxide can be poured off and
some idea gained of the temperature of the
molten iron underneath by pouring a lit
tie of it out on a steel plate or along the
side of a steel bar, when it will be seen
to cut channels and holes in the cold metal
like hot water upon ice.
The process was originally devised for
welding steel rails, a mold being formed
around the Joint and the molten aluminium
mixture poured in. In q minute or two the
rail ends became soft enough to be squeezed
together into a perfect. weld. The pro-
cess has already proved cheap and practical
for rail-joint welding, and seems destined
to find many other commercial uses. A
number of other applications have already
been suggested, such as the softenfng OF
spots on hard armor plate for the purpose
of drilling holes for bolts and fittings,
welding of steam pipes, casting new pieces
in broken cylinders. replacing broken teeth
in cogwheels, ETC. A very important pos
screw shaft at sea or OF welding any large
broken parts of machinery whose repair at
sea with the old devices has been quite i'm
possible. There are many smaller ways IN
which it may prove valuable. In the case
OF a broken bicycle or automobile frame a
SINAI box of this mixture would nable the
rider to form a serviceable cast weld around
the break when the user is remote from any
town or workshop. If the full heat Of the
furnace is not desired 1t may be decreased
to any point by mixing with the iron rust
either sand, lime or magnesia. The higher
the percentage of any of these substances
present the lower the temperature of the
furnace will be.
Metallic aluminium thus proves to be a
storehouse of heat in a very concentrated
form. the temperature of the electric arc
being, so to speak. locked up in such a
shape that it may be carried to places
where the production of the arc itself would
be extremely expensive, If not impossible.
There Is, in fact, in the aluminium furnace
a means of producing an intense and sharp
ly localized heat by the use of a box of
powder and a match, which may be carried
with perfect safety to places where the
other means of producing high tempera-
ture are out of the question. The discov-
cry is therefore one which has great COM
mercial as well as scientific value.