IMPROVEMENTS IN LAMPS FOR THE COMPUSION OR MAANPRIUM AND IN PREPARING MAGNESIUM FOR BURNING
Year: 1865

page_text: ⚫ LETTERS PATENT to Henry Larkin, of No. 6, Torriano Cottages, Leighton
Road, N.W., for the Invention of "IMPROVEMENTS IN LAMPS FOR THE
COMPUSION OR MAANPRIUM AND IN PREPARING MAGNESIUM FOR BURNING"
Sealed the 27th April 1866, and dated the 28th October 1865.
PROVISIONAL SPECIFICATION left by the said Henry Larkin at the
Office of the Commissioners of Patents, with his Petition, on the
28th October 1865.
HENRY LARKIN, of No. 6, Torriano Cottages, Leighton Road, N.W.,
5 do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
LAMPS FOR THE COMBUSTION OF MAGNESIUM, AND IN PREPARING MAGNESIUM FOR
BURNING," to be as follows:-
S
This Invention has for its object improvements in lamps for the combustion
of magnesium, and in preparing magnesium for burning. In order to obtain
0 light from magnesium I employ the metal in the state of powder. The lamp
is so arranged as to supply a continuous stream of the powder, and the light
is produced by the combustion of the stream of finely divided metal. At the
upper part of the lamp is a funnel or reservoir into which the finely divided
métal is placed, and it flows out at a small orifice at the bottom of the funnel
5 or reservoir. The stream flowing from the funnel or reservoir falls through a
tube considerably larger in diameter than the orifice of the funnel or reservoir,
and the metallic stream is ignited as it issues from the lower end of this tube,
which may be surrounded by a glass to protect the flame from draughts of air.

page_text: The stream of metallic particles in falling from the orifice of the funnel or
reservoir through the tube attains such a velocity as to prevent the magnesia
produced by the combustion choking the end of the tube; if the stream were
ignited immediately beneath the orifice of the funnel or reservoir this orifice
would almost immediately be thus choked. I find it convenient to mix the
metallic powder with sand or similar material to cause it to flow more freely
from the orifice, and to cleanse more perfectly the interior of the tube through
which it falls, and the intensity of the light may be regulated by employing
more or less sand or diluting material. In some cases I employ a screw or
other mechanical movement for insuring and regulating the supply of powder
from the reservoir into the tube.
In some cases I employ the magnesium in the form of ribbon or wire, and
in order to secure the regular and perfect combustion of the metal I arrange
the lamp in such manner that two or more magnesium ribbons or wires may
be fed forward towards a central point, where they are ignited, thus a regular
light is produced, one wire or ribbon compensating for the irregularity of the
other. When employing the magnesium in the form of ribbon I arrange the
lamp to feed it forward for burning when on edge or with its surfaces vertical,
in place of, as heretofore, on the flat or with its surfaces horizontal, thus the
bending of the ribbon in burning is prevented, and the ash falls clear. I
regulate the supply of the ribbon or wire by means of clockwork governed
by a pendulum or balance wheel in place of by a fan as is now practised.
SPECIFICATION in pursuance of. the conditions of the Letters Patent, filed
by the said Henry Larkin in the Great Seal Patent Office on the
28th April 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
LARKIN, of No. 6, Torriano Cottages, Leighton Road, N.W., send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of October, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Larkin, Her special licence that I, the said Henry Larkin,
my executors, administrators, and assigns, or such others as I, the said
Henry Larkin, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,

page_text: exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
LAMPS FOR THE COMBUSTION OF MAGNESIUM, AND IN PREPARING MAGNESIUM FOR
BURNING," upon the condition (amongst others) that I, the said Henry Larkin,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Henry Larkin, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
This Invention has for its object improvements in lamps for the combustion
of inagnesiumi, and in preparing magnesium for burning. In order to obtain
light from magnesium I employ the metal in a state of powder. The lamp
is so arranged as to supply a continuous stream of the powder, and the light
is produced by the combustion of this stream of finely divided metal. At the
upper part of the lamp is a funnel or reservoir into which the finely divided
metal is placed, and it flows out at a small orifice at the bottom of the funnel
or reservoir. The stream flowing from the funnel or reservoir falls through a
tube considerably larger in diameter than the orifice of the funnel or reservoir,
and the metallic stream is ignited as it issues from the lower end of this tube,
which may be surrounded by glass to protect the flame from drafts of air.
The stream of metallic particles in falling from the orifice of the funnel or
reservoir through the tube attains such a velocity as to prevent the magnesia
produced by the combustion choking the end of the tube; if the stream were
ignited immediately beneath the orifice of the funnel or reservoir this orifice
would almost immediately be thus choked. I find it convenient to mix the
metallic powder with sand or similar material to cause it to flow more freely
from the orifice, and to cleanse more perfectly the interior of the tube through
which it falls, and the intensity of the light may be regulated by employing
more or less sand or diluting material.
a
Figure 1 shews a vertical section of a lamp arranged and combined accord-
ing to this part of my Invention, wherein magnesium in the state of powder is
burned. The magnesium is reduced to a state of powder, and it is sifted
through a fine sieve in order to separate the larger particles and to obtain a
powder in which the grains are as nearly as may be of a size. The powdered

page_text: metal I mix or combine with sand, or it may be ground flint or glass or like
matter slightly coarser in the grain than the metallic powder; this addition
will cause the metallic powder to flow more freely and regularly through an
orifice, and at the same time will dilute the metallic powder and modify the
intensity of the light obtained by its use. I have found that combining one
part by measure of the powdered metal with two or three parts of sand or
other like material produces a very good result, but a larger or less proportion
may be used according to the effect desired to be obtained.
The form of lamp employed in carrying out my Invention may be varied,
but I prefer the arrangements shewn in the Drawings. The mixed or com-
bined matters are placed in the hopper-shaped vessel a, having at its lower
end a perforated plate or strainer a³, the perforations or openings in which are
to be just sufficiently small to arrest any substance which would be unable to
pass through the opening or orifice 6¹ of the outer funnel or hopper-shaped
vessel 6; there is also an intermediate hopper c with a strainer c¹ at its bottom
wl ich serves as a further security against any pieces of matter passing to the
opening c which would not readily pass through it. The outer vessel b is
closed at top by a cover d, in order not only that dust and other matters may
be excluded, but also to facilitate the use of gas as a means of giving steadiness
t> the light; the use, however, of gas, although desirable, is not essential,
and may be dispensed with. e is a gas supply pipe by which gas can be
passed into the containing vessel a, this supply pipe is to have a cock on
it to adjust the quantity of gas supplied to the apparatus; f is a valve actuated
by a thumbscrew for letting on or cutting off the stream of powdered metal.
The metallic powder combined with sand or other substance is delivered past
this valve into the tube g, and descends into the chamber h, the sides of which
are of glass and may be of any desired form. This chamber in which the
combustion takes place has a receiver i at the bottom into which the uncon-
sumed matters descend; there is also a chimney or outlet k for the escape of
the products of combustion, and an inlet 1 for the supply of atmospheric air to
the chamber. In some cases when great light is required two or more tubes g
may be used in combination. The stream of magnesium powder is ignited at
the lower end of the tube 9, and this is conveniently done, when gas is employed,
by first lighting the gas, which when turned on will flow through the tube g;
through the small flame thus obtained the powdered metal is allowed to
descend by turning the screw of the valve f and allowing it to fall back. The
use of gas is further advantageous in keeping the magnesium flame at a proper
distance from the mouth of the tube g. In some cases, in order to insure a
regulated, uniform, and constant delivery of the metallic powder, it may be

page_text: without the assistance of sand or other similar material, I employ a screw or
instrument which is driven by clockwork or other maintaining power and
actuates a moving surface.
Figures 2 and 3 show an arrangement for thus regulating the delivery of
the powder. A grooved wheel m is placed directly below the outlet or
orifice b', which in this case may be of any sufficient size to allow the metallic
powder to pass readily through it; the wheel is then made to rotate uniformly..
at a slow rate by means of a screw n actuated by any suitable maintaining
power, by which means the supply of metallic powder from the containing
vessel or holder may be regulated according to the amount of light required.
In some cases I employ the magnesium in the form of ribbon or wire, and in
order to secure the regular and perfect combustion of the metal I arrange
the lamp in sucli manner that two or more magnesium ribbons or wires may
be:fed forward towards a central point, where they are ignited; thus a regular
light is produced, one wire or ribbon compensating for the irregularity of the
other.
Figures 4 and 5 show a plan and side view of parts of a lamp for burning
magnesium wire, or it may be narrow strips of magnesium. In this arrange-
ment there are two pair of tubes or passages or suitable guides through which
the wires or strips are fed up to the points of ignition, but one pair only, or
any number of pairs, may be employed so long as the arrangement shown be
retained whereby the ends of the wires or strips are fed forward towards each
other, so that the end of each, whenever from any irregularity in the metal its
combustion slackens, will enter the flame of the other; thus the constant
steady burning of the lamp is ensured. o, o, are the tubular passages through
which the wires of magnesium p, p, are fed by means of two wheels 9, I,
which are to be propelled by clockwork or other mechanical power.
I
Figures 6 and 7 show the same principle applied to flat strips or pieces of
magnesium which also are to be fed uniformly forward by clockwork or other
mechanical power.
When employing the magnesium in the form of ribbon,
arrange the lamp to feed it forward for burning when on edge or with its
surfaces vertical in place of, as heretofore, on the flat or with its surfaces
horizontal; thus the bending of the ribbon in burning is prevented, and the
ash falls clear. Three or more wires, strips, or ribbons of the metal may be
fed towards a common centre, as in Figure 8.
What I claim is the arranging lamps for burning magnesium in the form
of powder in such manner that the powdered metal flowing from an orifice is
caused to pass through a tube or passage which conducts the stream of metal
away from the said orifice before it becomes ignited.

page_text: I also claim the application of a mechanical movement, as is shown at
Figures 2 and 3, for the purpose of insuring and regulating the supply of
powder from the reservoir into the tube or passage aforesaid.
I also claim the preparing magnesium for use in lamps by mixing the
powdered metal with sand or similar inert diluting material.
I also claim the arranging lamps for burning magnesium in the form of
ribbon or wire in such manner that two or more ribbons or wires may be fed
forward towards a central point, where they are ignited.
In witness whereof, I, the said Henry Larkin, have hereunto set my
hand and seal, this Twenty-sixth day of April, in the year of our
Lord One thousand eight hundred and sixty-six.
HENRY LARKIN. (L.S.)