THE CONSTRUCTION OF A PRESSURE OR FOUNTAIN LAMP, TO BURN WITH SAFETY PROM IGNITION IN THE OVERFLOW, AND FROM EXPLOSION, ALL BITUMINOUS, CARBONACEOUS, AND RESINOUS OILS, SPIRITS, AND NAPHTHAS, OR ADMIXTURES THEREOF; ALSO THE PRODUCTS OF RANGOON EARTH OIL, OR PETROLEUM; ALSO TO ADAPT ALL PRESSURE AND FOUNTAIN LAMPS TO BURN THESE SUBSTANCES WHICH ARE POUND TO IGNITE IN THE OVERFLOW, AND CAUSE EXPLOSION, &C., IN ALL SUCH LAMPS AS AT PRESENT CONSTRUCTED
Year: 1857

page_text: ETTERS PATENT to James Broad, Coach Spring and Carriage Lamp
Maker, of Nos. 149 and 150, Drury Lane, Holborn, London, for the
Invention of "THE CONSTRUCTION OF A PRESSURE OR FOUNTAIN LAMP, TO
BURN WITH SAFETY PROM IGNITION IN THE OVERFLOW, AND FROM EXPLOSION,
ALL BITUMINOUS, CARBONACEOUS, AND RESINOUS OILS, SPIRITS, AND NAPHTHAS,
OR ADMIXTURES THEREOF; ALSO THE PRODUCTS OF RANGOON EARTH OIL, OR
PETROLEUM; ALSO TO ADAPT ALL PRESSURE AND FOUNTAIN LAMPS TO BURN
THESE SUBSTANCES WHICH ARE POUND TO IGNITE IN THE OVERFLOW, AND CAUSE
EXPLOSION, &C., IN ALL SUCH LAMPS AS AT PRESENT CONSTRUCTED."
Scaled the 5th February 1858, and dated the 17th December 1857.
COMPLETE SPECIFICATION filed by the said James Broad at the Office
of the Commissioners of Patents, with his Petition and Declaration, on
the 17th December 1857, pursuant to the 9th Section of the Patent
Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
BROAD, Coach Spring and Carriage Lamp Maker, of Nos. 149 and 150, Drury
Lane, Holborn, London, send greeting.
WHEREAS I am in possession of an Invention for "THE CONSTRUCTION OF
A PRESSURE OR FOUNTAIN LAMP, TO BURN WITH SAFETY FROM IGNITION IN THE
OVERFLOW, AND FROM EXPLOSION, ALL BITUMINOUS, CARBONACEOUS, AND RESINOUS OILS,
SPIRITS, AND NAPTHAS, OF ADMIXTURES THEREOP; ALSO THE PRODUCTS OF RANGOON
EARTH OIL, OR PETROLEUM; ALSO TO ADAPT ALL PRESSURE AND FOUNTAIN LAMPS TO

page_text: BURN THESE SUBSTANCES WHICH ARE FOUND TO IGNITE IN THE OVERFLOW, AND CAUSE
EXPLOSION, &C., IN ALL SUCH LAMPS AS AT PRESENT CONSTRUCTED," and have
petitioned Her Majesty to grant unto me, my executors, administrators, and
assigns, Her Royal Letters Patent for the same, and have made solemn
declaration that I verily believe myself to be the first and truo Inventor
thereof.
NOW KNOW YE, that I, the said James Broad, do hereby declare that
the following Complete Specification under my hand and seal, fully describes
and ascertains the nature of my said Invention, and the manner in which the
same is to be performed, that is to say:-
My said Invention consists in the construction of a pressure or fountain
lamp to burn without smoke, smell, or ignition in the overflow or "catching
down," or "backing" as it is called, or dropping in flames such oils, spirits,
napthas, &c., as are found to be subject so to do in all pressure and fountain
lamps hitherto invented, and particularly, as an instance, in the lamp called the
"moderateur" lamp, and also for adapting all pressure and fountain lamps
now in use, including the said "moderateur" lamp to burn such substances,
namely, all the products obtained by any process of manufacture or distillation
from petroleum or Rangoon earth oil, Persian or other napthas, boghead coal,
common coal, splent or slate coal, peat, Trinidad or other asphaltum, pitch,
turpentine, and rosin, also parafine oil, dead oil, and naphtha, obtained from
coal tar, spirits of turpentine, camphine, olefiant gas, wood, naphtha, and all
bituminous, carbonaceous, and resinous oils, spirits, and naphthas, whether
vegetable or mineral, or combinations or admixtures thereof. For my purpose I
prefer to construct the reservoir of my lamp in the form of a cylinder, and to
use a spiral spring piston with valves, rack, &c. To the top of this cylinder or
reservoir, I attach a metal framework about three inches high, to this frame-
work I aflix my rack, wick, clevator, regulator, &c., and from this frame-
work I carry up two tubes about the eighth of an inch apart, one inside the
other, admitting air through the centre tube on the Argand principle, (or I
can use and claim to use a flat, crescent, or other shaped wick or succession of
wicks simultaneously as herein-after described.) I construct the outer of
these tubes about three inches long, and an inch and a half shorter or there-
abouts than the inner tube, which inner tube will therefore be about four
inches and a half long, and about half an inch from the top of the inner tube;
I affix to the inner surface thereof a third short tube extending to the same
height as the inner tube, detached at the top, and attached at the bottom by a
nonconductor, and so forming a slit down which the minute particles of oil
(which "weep" or move down in the shape of moisture from all lamps in the

page_text: process of burning) pass, and through this slit and through perforations (made
for the purpose) back again on to the wick; this contrivance prevents smell
from the inside tube, which would otherwise take place by the evaporation of
the oil which so "weeps" over. Over these tubes I place a metal chamber
about two inches long, terminating at the upper end in a burner which stands
level with the top of the inside tube, and at the lower end in a nonconductor,
and which nonconductor rests on the outer tube about half an inch from the
top of it. I perforate or leave a space in this nonconductor for the passage of
the unconsumed oil back to the reservoir, and I so construct this chamber as
to cover in the wick from the exterior air, but to stand clear of it at a distance
of about the third of an inch all round, leaving the whole extent of wick so
enclosed untouched by it (and so to speak) "naked" on the outer surface,
the inner surface of my wick being supported by and working on the inside
tube. From the outer surface of my wick so left "naked" the superfluous
oil not consumed by the flame flows into the chamber instead of over the
point of light (as in other pressure lamps), and from the chamber down a tube
affixed for the purpose into the cylinder or reservoir, and is again pressed up;
by this contrivance I prevent ignition of the overflow, and all danger of
explosion, &c., resulting therefrom. As before described, I fit my wick on
the inner tube, and work it up by my rack until it protrudes through the top
of the above-described chamber. To this chamber I affix a ring of metal or
short tube next to the space through which the wick is so made to protrude,
thus forming a second "slit," and through this slit the oil which "weeps
over from the outside of the wick descends into the chamber, and thence into
the reservoir. This contrivance prevents smell from the particles of oil which
would otherwise evaporate, and cause it on the outside of the chamber. My
wick which it is essential should work closely on the inner tube, is so
woven as to be elastic, and enlarged at the lower end to facilitate the fixing of
it in trimming my lamp, and I singe the loose fibres off the surface to prevent
small globules of oil collecting thereon, and as these products are "thin" or
"light," I make the tube (through which they are pressed to the burning
chamber) very small, and it is liable to be choked by the smallest particles of
dirt; to obviate this, I placo over the valve in the piston a piece of fine wire
gauze, and inasmuch as the before-named products are "delicate" and of
subtle nature, and vary in the burning with the slightest variation either in
supply or heat of the tubes or chamber, and are liable to smoke and smell by
such variations which would both be caused by the pressure ceasing for
a few seconds, I affix an indicator in the form of a small bell, which by means
of a spring I cause to be struck the instant the lamp has run down, thus

page_text: marking the precise moment when rewinding is required. I use a glass
chimney, and I trim and light my lamp by removing the chamber and chimney,
and drawing the wick down the outside of the inner tube, and attaching it to
the wick regulator, then replacing the chamber and raising tho wick through
it by means of the wick elevator, replacing the chimney when the lamp is
lighted. I cover in all my oil courses to prevent smell from the "raw" oils,
&c., as the above-named products all emit offensive odours without the appli-
cation of heat. I claim to burn these lamps either with or without a button, and
with or without a shoulder in the chimney, and I obviate the necessity of tho
shoulder in the chimney by a hollow metal cap running up outside the chamber,
and terminating immediately below the point of light for burning flat, crescent,
or other shaped wicks. I construct a chamber with a nonconductor as before
described, and cause the oil to flow up through metal channels without
admitting air as in the "Argand" principle; I leave a portion of the wick or
wicks (hich work up the channels) "naked" by means of this chamber,
and frohich the superfluous oils, &c., drain back into the cylinder, and
this prevents danger from overflow (as before described) at the point of light.
I also form a slit round the outside of the burner to take down the oil that
"weeps" over, and prevents smell as before described. My lamp is essentially
a pressure or fountain lamp, and not a mere detached lamp of ordinary
construction aflixed by scrowing on, &c., to the pressure lamp, and by such
means only making use of the point where the oil overflows in the place of a
reservoir from which to draw a supply by a detached wick and mero capillary
attraction. But I claim to exclude infringement of my right to burn the
above products in a pressure or fountain lamp by this or any other appliance.
Dated this Sixteenth day of December, in the year of our Lord One
thousand eight hundred and fifty-seven.
JAMES BROAD. (L.S.)