Year: 1885

page_text: I, ARTHUR BRIN of 7 Rue Gavarni Paris in the Republic of France, but at
present residing at 5 Sydney Street South Kensington in the County of Middlesex,
Engineer do hereby declare the nature of this Invention to be as follows:-
Electric arc lamps have heretofore had the disadvantage of requiring frequent
renewal of the carbons or candles between which the arc is formed. The object
of my Invention is to remedy this disadvantage by employing in place of the
various forms of carbons a basic product of alumina, magnesia and silex which
does not undergo any molecular disintegration under the action of the voltaic arc.
This basic product may be employed in any suitable construction of lamp but I
prefer to interpose it between two carbon or other conductors to which the
respective line wires to and from the lamp are attached, the said carbons being
perforated longitudinally and the basic product being in the form of a small slab
or disc hollowed out at one place or at several places the better to distribute
the light.
J. HENRY JOHNSON,
Agent for the said Arthur Brin.
mproveme
I ARTHUR BRIN of 7 Rue Gavarni Paris in the Republic of France but at
present residing at 5 Sydney Street South Kensington in the County of Middlesex
Engineer do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
Electric am lamps have heretofore had the disadvantage of requiring frequent

page_text: my Invention is to remedy this disadvantage by employing in place of the various
forms of carbons a refractory material made of silica magnesia and alumina the
mixture being subjected to great pressure and if desired to a high temperature. I
do not limit myself to any precise proportions of the ingredients named but have
found the following to answer well videlicit silica 10 parts by weight magnesia
83 parts by weight and alumina 7 parts by weight. I reduce and sift these
materials so as to obtain them in as fine a condition as possible and I then put them
in a press in moulds of the required form and apply pressure (preferably hydraulic
pressure) amounting to about 700 kilogrammes per square centimetre of surface.
This compound material I find does not undergo any molecular disintegration under
the action of the voltaic arc. This refractory material may be employed in any
suitable construction of lamp but I prefer to interpose it between two carbon or
or other conductors to which the respective line wires to and from the lamp are
attached. The said material is perforated longitudinally and takes the form of a
small slab or disc hollowed out or perforated at one place or at several places the
better to distribute the light.
Figure 1 of the accompanying Drawing illustrates this form of lamp. A is the
body or support of the lamp which is here shewn as being a suspended one. B. C.
are arms secured to the said body and acting as supports for the conductors D. E
which are adjustably secured therein and serving also if required as attachments of
the line wires b, c. The said body A carries a holder which supports a disc or
piece F of the refractory material herein before mentioned-This piece F is shewn
in side view in Figure 2. It is perforated opposite the centres of the conductors ED
so that the arc strikes through the perforation, and at this place when the current
is turned on to the lamp the arc is exhibited and the material F thus used emits a
very powerful light and does not burn away or become altered in its constitution.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is,
1st An electric are lamp wherein is employed a disc or piece of the refractory
material herein before mentioned for the purpose described.
2nd An arc lamp constructed or arranged as hereinbefore described and illustrated
in the accompanying drawings.