IM- PROVEMENTS IN ELECTRIC LIGHTING BY APPLYING AN IMPERISHABLE SUB- STITUTE FOR THE CARBONS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE IN PART TO OTHER APPLICATIONS OF ELECTRICITY
Year: 1878

page_text: LETTERS PATENT to Joseph Norman Aronson, of 37, Bedford Row, in the
County of Middlesex, Gentleman, and Henry Brougham Farnie, of Great
Marlborough Street, in the said County, Author, for the Invention of "IM-
PROVEMENTS IN ELECTRIC LIGHTING BY APPLYING AN IMPERISHABLE SUB-
STITUTE FOR THE CARBONS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE IN
PART TO OTHER APPLICATIONS OF ELECTRICITY."
Sealed the 15th April 1879, and dated the 18th October 1878.
PROVISIONAL SPECIFICATION left by the said Joseph Norman Aronson and
Henry Brougham Farnie at the Office of the Commissioners of Patents on
the 18th October 1878.
JOSEPH NORMAN ARONSON, of 37, Bedford Row, in the County of Middlesex,
Gentleman, and HENRY BROUGHAM FARNIE, of Great Marlborough Street, in the
said County, Author. "IMPROVEMENTS IN ELECTRIC LIGHTING BY APPLYING AN
IMPERISHABLE SUBSTITUTE FOR THE CARBONS, SUCH IMPROVEMENTS BEING ALSO
APPLICABLE IN PART TO OTHER APPLICATIONS OF ELECTRICITY."
This Invention relates to improvements in electric lighting by applying an
imperishable substitute for the carbons, such improvements being applicable also in
part to other applications of electricity.
For the purposes of our Invention we use ruthenium, osmium, and rhodium.
These may be combined in any proportions or any two may be combined in any
proportions, or any one may be used singly. These substances when mixed (or
single if so used) are, by preference, placed in a tubular holder made of non-
conducting material, and capable of withstanding the necessary heat; or the above
substances may be mixed up with a non-conducting material, such as plaster of
Paris, asbestos, or other like and suitable substance. The wire of communication is
held by the tubular holder and brought into contact with the above-named
substance or substances, or with the compound as mixed with the plaster of Paris

page_text: or other material. So applied the substance or substances are used much in the
same way as carbon points, that is, the extremities may be brought into near
contact, and the electric light be so produced, or in some cases the light may be
produced by rendering a quantity of the substance or substances incandescent by
passing the current through it.
Combined with any or all of the above substances may be added any desired
quantity of any known conducting or non-conducting material to increase or decrease
the resistance as may be required.
We do not confine ourselves to any form of mechanism with which to use our
Invention, nor do we confine ourselves to any particular formation of the substance
or substances for use.
The substance is indestructible, and may be applied to other purposes in connection
with electricity as with carbon.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Norman Aronson and Henry Brougham Farnie in the
Great Seal Patent Office on the 18th April 1879.
JOSEPH NORMAN ARONSON, of 37, Bedford Row, in the County of Middlesex,
Gentleman, and HENRY BROUGHAM FARNIE, of Great Marlborough Street, in the
said County, Author. "IMPROVEMENTS IN ELECTRIC LIGHTING BY APPLYING AN
IMPERISHABLE SUBSTITUTE FOR THE CARBONS, SUCH IMPROVEMENTS BEING ALSO
APPLICABLE IN PART TO OTHER APPLICATIONS OF ELECTRICITY."
According to our Invention we take osmium and treat it and form it into burners
or points for the electric light as follows:-
The osmium in a powdered or granulated condition is first partially consolidated
by heat or pressure or both. When by heat a convenient method is as follows:-
It is moderately compressed into a mould the size and form of the burner or point
required. The mould is formed of, say, lime or plaster of Paris, and the osmium is
covered in at both ends; the mould is then put in a muffle, and the whole submitted
to a white heat or a heat sufficient to cause the particles of the osmium to con-
solidate, the application of the heat lasting for, say sixty minutes,. more or less,
according to the degree of heat employed; the block is then removed from the fire,
and when broken the osmium is found to have become consolidated sufficiently to
preserve its form, but is still very brittle. If the heat process described is to be
dispensed with the osmium must be compressed into a strong mould, say of steel,
by a very great pressure, hydraulic or otherwise. A pressure of, say, one thousand
to twelve hundred tons to the inch will be found sufficient to consolidate the
osmium without the subsequent application of heat sufficiently for it to preserve its
form for the subsequent process. The points or burners thus prepared, either by
the heat or the pressure process, are placed in holders of suitable conducting power
(say of carbon, which I prefer), and placed in the electric circuit in the same way
that carbon points would be used, and either singly in a closed circuit or in
duplicate with an arc between them. A powerful electric current is now passed
through them when the electric light will be obtained in the one case by in-
candescence, and in the other case in the arc.
A large sized Gramme or other similar machine will be found sufficient to effect
the object desired. The powerful electric current causes the osmium points or
burners to more or less fuse, and become closely consolidated and homogenous, and
they will then be found to bear any subsequent application of the electric current
sufficiently strong for all ordinary purposes of the electric light without again
fusing, and without any perceptible consumption or degree of perishing or
deteriorating; they are thus calculated to last an indefinite length of time for
obtaining the electric light.
Various forms of holders may be employed to hold the osmium points whilst
fusing them by the electric current. A convenient form is to enclose the points
within two hollow carbon cylinders placed vertically side by side, sufficiently near
to one another to obtain the electric light through the arc between them. As the
carbons burn away from the top downwards the osmium within gradually fuses
and settles down until sufficiently consolidated when they are ready for use for
obtaining the electric light, as with ordinary carbons. As the fumes given off from
the osmium whilst being thus fused are exceedingly injurious to inhale I neutralise
them in the following manner :-The burners are enclosed in a glass cylinder
having a wire saucer or cap over its upper end; in this saucer is placed cotton wool

page_text: saturated with glycerine, and over this powdered charcoal. This effectually prevents
the escape of injurious fumes.
In witness whereof, I, the said Joseph Norman Aronson, on behalf of myself
and the said Henry Brougham Farnie, have hereunto set my hand and seal,
this Eighteenth day of April, in the year of our Lord One thousand eight
hundred and seventy-nine.
JOSEPH NORMAN ARONSON. (Ls.)