Evening star. [volume] (Washington, D.C.) 1854-1972, 1893-05-31
ELECTRIC HEATING.
A New Method in Germany Described in q
Consular Report.


Consul General Mason at Frankfort writes
to the State Department of a new method Of
electric heating as follows:
discovery SO original and so wide in its
practical application that it is believed to open
new and important chapter in the use of
electricity for heating purposes has recently
been announced fromBrussels and tested atBer-
lin. The invention is the joint achievement of
two Belgian scientists-Mrs. Lagrange and
and Hoho-who few days ago applied to the
imperial German patent Office for patents on a
new method of heating. melting and refining
metals by means of electrical heat. The means
as designated i'll their claim, were so simple
ana the results as therein described SO incred-
ipie that the patent examiners demanded that
before issuing the patent practical demonstra-
tion OF the process should be made in their
presence. The matter was referred to an en-
lnent and disinterested electrical expert in
berlln. who made the first ESSAYS in his private
iaooratory and was so delighted with the result
tnat he asked by telegraph permission of the
inventors to repeat the demonstrations before
ne, eTec'BTo-.echnical society at the German
capital PERMISSION was readily granted, and
tne experiments were performed before a
group on expert electricians with brilliant sue
cess From the account given by one of the
eAperts VINO was present at these demonstra-
.ionS ana from various other Isources the fol-
loving report OF the new process has been
derived.
THE APPARArUs
The apparatus consists of glass or porcelain
vase. which may be of any size conveniently
adapted to the purpose, provided with lining
OF lead. connected with a strong conductor of
positive electricity. The vase is filed 10 three
1ourths Its capacity with acidifed water. A
pair OF iron tongs with insulated handles is at
tached by flexible conductor to the negative
n AZ oil sr,,
ordinary dynamo. With this simple and mex
pensive equipment the following phenomenon
is produced:
The electrical current having been switched
on, bar OF wrought iron or other metal is
taken up with the tongs and plunged into the
water within the vase. Immediately the water
begins to boil at the point of contact: the i'm
mersed portion OF the iron rises quickly to a
red. then to a white heat, and emits a stream
OF brilliant white light. In few moments the
neat becomes SO intense that the iron melts
and falls of IN bubbles and sparks. leaving a
clear. glowing surface in perfect condition for
welding. The heating process has been SO
RAPID that neither the water nor the end of the
BAR, held within the tongs, have been more
imam signify warmed, and. the current
being switched of, the bar, with its submerged
end glowing, may be readily held in the naked
hand. II. instead OF bar of metal a stick of
carbon Is used, the heat in a few minutes pro-
duces detached fragments of amorphous car
Don winch proves scientifically that temper
AZURE OF 4, 900 degrees Celsius has been deyel-
oped. The rapidity of the heating and the
limit OF temperature to be reached are easily
and accurately governed by the strength of the
current employed. SO that the whole process is
under the absolute control of the operator.
During the recent experiments at Berlin tine
measuring instruments registered a tension of
l2O volts and an energy Of 200 amperes
1t was estimated that fully so per cent of the
current was directly utilized as heat, whereas
the practical limit of such utility has not
hitherto exceeded 20 per cent 1t is stated by
the inventors that by employing a still stronger
current temperature of 5000 degrees Celsius
has been developed. The mechanical import
ance OF this fact will be apparent when it is
remembered that this is degree of heat nearly
three times greater than that required to eI-
tract iron from the ores, the most refractory Of
which fuse at about 2, 200 degrees.
TIE PROCESS.
Divested of all merely technical phraseology1
and reduced to Its simplest terms, the process
under consideration may be explained as fol-
lows: One of the weil-known effects of cleo :
triclty Is to separate compound fluid bodies
through which 1t passes into their primitive,
Clements. The current, passing through the
tongs and metallic bar into the water, decom-
poses the latter into its two gaseous elements
oxygen an hydrogen. The oxygen is attracted
and gathered on the relatively large surface
OF the lead lining and produces no noticeable
effect. The hydrogen, on the other hand,
gathers around the immersed portion of the
par; and. as this has a comparatively limited
surface area it is Immediately surrounded with
a close envelope or jacket of hydrogen which,
being bad conductor OF electricity. creates a
powerful resistance to the passage Of the cur
rent and thus develops the heat which causes
the bar to glow and melt 1t is merely an an
plcation of tue weil-known law that friction
or resistance to the passage of an electrical
current causes heat. and the apparent paradox
of a piece of cold metal plunged into cold
water rising rapidly to a melting glow is as
simply and clearly explained as the incandes<
cence OF platinum coil in a vacuum bulb.
1t is as yet too early to form any definite es-
innate OF the practical range of this discovery
or Its commercial value. Thus far il has been
applied experimentally only TO the welding OF
various metals, but with such success that 10
promises, IN that special field to inaugurate a
complete revolution. Hitherto electrical
energy transformed into heat has found but
few successful applications in industry. For
welding purposes it has been not only too ex-
penslve for general adoption, but il has en-
tailed certain technical defects which have
proven serious and difficult to overcome. As
the temperature OF the electrical furnace has
been heretofore difficult TO govern the iron
has often been overheated to the point of par
tial melting. This seriously affects its quality.
as on cooling the metal does not resume its
original hbrous texture. but becomes crystal
line, with an important loss of tensile strength
Another disadvantage has resulted from the
fact that iron, when used for practical pur-
poses, is rarely or never entirely pure, but
contains more less carbon. Steel ana
wrought iron contain less carbon than cast
iron, and when heated il tLs ordinary electro
cal furnace, where the heat is generated by
the passage of the current between two carbon
points. particles Of loose carbon width have
been detached by the current combine with the
hot metal and convert it into something
analogous to cast iron.
DIFFICULTIES MASTERED
All these difficulties are apparently complete.
ly mastered by the newly discovered process
above described For welding purposes i, is pro.
nounced perfect. The clean envelope of hydro-
gen which surrounds the heated metal pre-
vents oxidation. and the welding surface is left
free from the effects Of sulphur and other i'm
purities. which are always present when iron
Is heated by a coal fire in an ordinary forge.
The quality which entails the largest poss,bili-
ties. and which has been as yet only supertici-
ally investigated. is the capacity of this process
TO heat quickly and to any desired Temperature
the end or submerged surface of mass of iron
while the remainder of the mass is left cool
and comparatively unaffected by the heat II
is believed that this may lead TO important re-
suits in the hardening and tempering of armor
plates and other objects in iron and soft steel
In which great resistance to penetration or abra-
sion by friction is requisite, while preserving
the interior tough and fbrous to resist concus-