IMPROVEMENTS IN RAILWAY CARRIAGE, STREET, AND OTHER GAS LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER PURPOSES." SP
Year: 1881

page_text: This Specification was, upon the 14th day of December 1886, amended under
Sections 18 to 21 of the Patents, Designs, and Trade Marks Act, 1883.
[The Amendments are shown in erased and italic type.]
LETTERS PATENT to Frank William Clark, of Millbank Street, in the City of.
Westminster, Engineer, for an Invention of "IMPROVEMENTS IN RAILWAY
CARRIAGE, STREET, AND OTHER GAS LAMPS OR LANTERNS, THE IMPROVEMENTS
BEING ALSO APPLICABLE TO OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frank William Clark at the
Office of the Commissioners of Patents on the 1st July 1881.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY CARRIAGE, STREET. AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed by my improved
construction of lanip the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows -
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them-the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below the outer tube which serves for the inlet of the air into a chamber
formed by the body of the lamp and the herein before described tubes and suitably
closed from this chamber the air previously heated in its passage between the two
tubes is conveyed by a pipe or pipes to the gas burner or burners or gas flame or
flames, the said pipe or pipes passing either outside or inside the gas flame or
flames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement herein before described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank William Clark in the Great Seal Patent Office on the
31st December 1881.
.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY-CARRIAGE, STREET, AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS DEING ALSO APPLICABLE-TO-OTHER
PURPOSES:"
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than bitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed; by my improved
construction of lamp, the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows:-
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them; the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below (or only above) the outer tube, which serves for the inlet of the air into
chambers formed by the body of the lamp and the herein before described tubes,
and suitably closed from these chambers the air previously heated in its passage
between the two tubes and case or body is conveyed to the gas burner or burners
or gas flame or flames, the said hot air passing either outside or inside the gas flame
or flames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement hereinbefore described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating
purposes.
In order to make my Invention better understood I will now describe the same
by reference to the accompanying Drawing in which Figure 1, is a side elevation,
and Figure 2, a vertical section of a lamp or lantern constructed according to my
Invention and suitable for lighting a railway carriage; Figure 3, is a plan and
Figure 4, is a horizontal section of the same; Figure 5, is a vertical section of a
lamp in which the inner concentric tube serves for the air inlet, and Figure 6, is a
horizontal section on line A, B, of Figure 5. Similar letters of reference in all the
Figures represent similar or corresponding parts.
I will first describe the railway carriage lamp shewn in Figures 1, 2, 3, and 4.
a, a, is the case forming the lamp body; b, the usual glass of the same; c, the
cover and e, are the two concentric tubes with a space f. (forming a chamber)
between them; the inner tube d, forms the chimney and extends above the outer
tube e, as shewn; these tubes d, and e, are connected together at the bottom by the

page_text: reflector I: and at top by the cover c; h, is the chamber formed by the lamp body a,
and the outer tube e; i, cover to the same with inlet tubes j, j for admitting air
and which are provided with any suitable arrangement to allow of their being
more or less opened or closed so as to regulate the quantity of air supplied to suit
différent qualities of gas and the size of the burner; k, k, are air inlet openings in
the outer tube e, also provided with means of regulating the supply of air; to
secure an air tight joint between the lamp case and the cover i, I provide the body a,
with an inclined flange 1, on which is screwed by the ring m, an india rubber
washer n so that when the cover i, is dropped into its place the inner part of the
upper surface of the washer always bears against the under surface of the cover i,
the weight of the cover inflecting the rubber so that even if the cover i, jumps, the
india rubber rises being in tension and follows the movements of the cover i, thus
keeping the joint air tight; o, is the ordinary spring fastening of the lamp; p, the
usual handle; q, is the hinge which is screwed to the flange, on the lamp body a
the hinge, serves as the inlet for the gas which enters at s, and passes through
the tube t, and through the cover c, into the coiled pipe u, shewn placed between
the tubes d, and e, but the said coil may also be placed in the chimney or in any
other suitable position; the coil u, conducts the gas to the burner v, by the tube w;
,, are tubes for conducting heated air from the chamber f, to near the point of
ignition; y, y, is an opening between the reflector g, and the lamp body a, through
which air passes from the chamber h, around the glass b, thereby preventing the
glass from becoming too hot, the said air at the same time becomes warmed before
passing to the flame or flames; , is a muffer or wind guard of any suitable con-
struction; a', is a tapered tube within the chimney to prevent down draught.
The action of the improved lamp is as follows:-
The gas entering through the inlet pipe t, passes into the coil u, and thence to the
burner by the pipe : upon the gas being ignited a draught is formed in the
chimney, and the air will enter the lamp through the inlets, and j, and will pass
into the chambers f, and the air which passes through the chamber, becomes
heated in its passage and passes in the heated state to the flame through the
tubes, the air from the chamber h, passes through the opening y, and around the
glass, and under the reflector g, and serves to keep the glass b, and reflector y,
from becoming too hot, the said air itself, thereby becoming warmed before it
reaches the flame.
From this construction and arrangement of lamp it will be understood that the
gas before it reaches the burner will be heated by passing through the coil in the
hot air chamber f, and the air for the combustion being also heated, a
economical light will be obtained.
more
In cases where it is required to enrich the gas before it passes to the burner, it
may be caused to pass through a suitable carburetter conveniently placed in the
hot air chamber f
In Figures 5 and 6 of the Drawing I have shewn the arrangement of lamp
I prefer to adopt when the inner concentric tube serves for the air inlet, a lamp of
this construction being specially suitable for use as a street lamp.
a, is the lamp body; b, the glass; c, the cover; d, and e, the concentric tubes;
g, the reflector; h, the chamber formed by the lamp body a, and the outer
tube e; i, cover to same; j,j, air inlets; k, k, the air inlets in the outer tube e; u, is
the gas supply pipe which I use in this arrangement instead of a coil as herein-
before described; between the inner tube d, and the gas pipe u, I provide an
additional pipe d', the space between the two tubes forming the chimney; and the
space between the tube d', and the gas pipe u, forming the heated air chamber
corresponding with the chamber in the arrangement hereinbefore described and
shewn in Figures 1, to 4. In this arrangement a ring, or an argand or other
suitable burner or burners e, may be employed; e', is an earthenware or metal
continuation of the tube d', such tube e¹, being perforated if found desirable for
causing a portion of the heated air to be more equally supplied to the interior
surface of the flame.

page_text: The action of this lamp will be understood without further description it being
substantially the same as that of the lamp hereinbefore described and shewn in
Figures 1 to 4.
The arrows shew the direction of the passage of the air which as will be seen by
the arrows is supplied in a heated state to the interior surface of the flame. If
the
e gas is to be carburetted the supply pipe u, passes through a carburetter placed
in any convenient position.
In cases where it is not required to carburet and heat the gas before burning,
the gas may be supplied from below instead of from above as hereinbefore
described and shewn.
My improvements are partly applicable to stoves and furnaces for heating
purposes us will be-understood without further-description.
"
Having thus described my said Invention and the best means with which I am
acquainted for carrying the same into effect I would have it understood that I do
not confine myself to the precise details herein laid down and shewn in the
Drawing as the same may be varied without departing from the peculiar
character of my Invention but what I do claim is : :-
Firstly. The general arrangement and construction of the improved lamp
hereinbefore described and represented in Figures 1 to 4 of the accompanying
Drawing.
Secondly. The modified construction of lamp hereinbefore described and repre-
sented in Figures 5 and 6 of the accompanying Drawing.
Thirdly. In a railway earringe-or other lamp I claim the method of heating the
air before it reaches the flame-by causing it to pass between concentric tubes
arranged and operating substantially as hereinbefore described and represented in
the-necompanying Drawing.
Fourthly. The method herein described of forming the joint between the lamp
body and cover by the employment of a rubber ring in combination with an
inclined flange substantially us and for the purposes hereinbefore-described and
represented in Figures 1, and 5, of the accompanying Drawing.
Fifthly. Thirdly The method of supplying heated air to the inner surface of the
flame by causing such air to pass through the chimney in its passage to the flame
substantially as hereinbefore described and represented in Figures 5, and 6, of the
accompanying Drawing.
Sixthly Fourthly The employment of the perforated continuation of e¹ from the
chimney for distributing the heated air over the interior surface of the flame as
herein before described and represented in Figure 5, of the accompanying Drawing.
In witness whereof I the said Frank William Clark have hereto set
my hand and seal this Thirtieth day of December in the year of our
Lord one thousand eight hundred and eighty one.

page_text: LETTERS PATENT to Frank William Clark, of Millbank Street, in the City of
Westminster, Engineer, for an Invention of "IMPROVEMENTS IN RAILWAY
CARRIAGE, STREET, AND OTHER GAS LAMPS OR LANTERNS, THE IMPROVEMENTS
BEING ALSO APPLICABLE TO OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frank William Clark at the
Office of the Commissioners of Patents on the 1st July 1881.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY CARRIAGE, STREET AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed by my improved
construction of lamp the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows:-
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below the outer tube which serves for the inlet of the air into a chamber
formed by the body of the lamp and the hereinbefore described tubes and suitably
closed; from this chamber the air previously heated in its passage between the two
tubes is conveyed by a pipe or pipes to the gas burner or burners or gas flame or
flames, the said pipe or pipes passing either outside or inside the gas flame or
flames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement herein before described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space betwen the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating
purposes.

page_text: SPECIFICATION in 'pursuance of the conditions of the Letters Patent filed by
the said Frank William Clark in the Great Seal Patent Office on the
31st December 1881.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY-CARRIAGE, STREET, AND OTHER GAS
LAMPS OR LANTERNS."
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed by my improved
construction of lamp, the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows:-
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them; the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below (or only above) the outer tube, which serves for the inlet of the air into
chambers formed by the body of the lamp and the herein before described tubes,
and suitably closed; from these chambers the air previously heated in its passage
between the two tubes and case or body is conveyed to the gas burner or burners
or gas flame or flames, the said hot air passing either outside or inside the gas flame
or Hames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement herein before described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
In order to make my Invention better understood I will now describe the same
by reference to the accompanying Drawing in which Figure 1, is a side elevation,
and Figure 2, a vertical section of a lamp or lantern constructed according to my
Invention and suitable for lighting a railway carriage; Figure 3, is a plan and
Figure 4, is a horizontal section of the same; Figure 5, is a vertical section of a
lamp in which the inner concentric tube serves for the air inlet, and Figure 6, is a
horizontal section on line A, B, of Figure 5. Similar letters of reference in all the
Figures represent similar or corresponding parts.
I will first describe the railway carriage lamp shown in Figures 1, 2, 3, and 4.
a, a, is the case forming the lamp body; b, the usual glass of the same; c, the
cover; d, and e, are the two concentric tubes with a space f, (forming a chamber)
between them; the inner tube d, forms the chimney and extends above the outer
tube e, as shown; these tubes d, and e, are connected together at the bottom by the

page_text: , to
reflector and at top by the cover c; h, is the chamber formed by the lamp body a,
and the outer tube e; i, cover to the same with inlet tubes j,j, for admitting air
and which are provided with any suitable arrangement to allow of their being
more or less opened or closed so as to regulate the quantity of air supplied to suit
different qualities of gas and the size of the burner; k, k, are air inlet openings in
the outer tube e, also provided with means of regulating the supply of air,
secure an air tight joint between the lamp case and the cover i, I provide the body a,
with an inclined flange l, on which is screwed by the ring m, an india rubber
washer n; so that when the cover i, is dropped into its place the inner part of the
upper surface of the washer always bears against the under surface of the cover i,
the weight of the cover inflecting the rubber so that even if the cover i, jumps, the
india rubber rises being in tension and follows the movements of the cover i, thus
keeping the joint air tight; o, is the ordinary spring fastening of the lamp; the
usual handle 7, is the hinge which is screwed to the flanger, on the lamp body a;
the hinge, serves as the inlet for the gas which enters at s, and passes through
the tube t, and through the cover c, into the coiled pipe u, shewn placed between
the tubes d, and e, but the said coil may also be placed in the chimney or in any
other suitable position; the coil u, conducts the gas to the burner v, by the tube w;
,, are tubes for conducting heated air from the chamber f; to near the point of.
ignition; y, y, is an opening between the reflector g, and the lamp body a, through
which air passes from the chamber h, around the glass b, thereby preventing the
glass from becoming too hot, the said air at the same time becomes warmed before
passing to the flame or flames; , is a muffler or wind guard of any suitable con-
struction; a', is a tapered tube within the chimney to prevent down draught.
The action of the improved lamp is as follows:-
The gas entering through the inlet pipe t, passes into the coil u, and thence to the
burner by the pipe w; upon the gas being ignited a draught is formed in the
chimney, and the air will enter the lamp through the inlets k, and j, and will pass
into the chambers f, and ; the air which passes through the chamber, becomes
heated in its passage and passes in the heated state to the flame through the
tubes a, a; the air from the chamber h, passes through the opening y, and around the
glass b, and under the reflector g, and serves to keep the glass b, and reflector g,
from becoming too hot, the said air itself thereby becoming warmed before it
reaches the flame.
From this construction and arrangement of lamp it will be understood that the
gas before it reaches the burner will be heated by passing through the coil in the
hot air chamber f, and the air for the combustion being also heated, a more
economical light will be obtained.
In cases where it is required to enrich the gas before it passes to the burner, it
may be caused to pass through a suitable carburetter conveniently placed in the
hot air chamber f.
In Figures 5 and 6 of the Drawing I have shewn the arrangement of lamp
I prefer to adopt when the inner concentric tube serves for the air inlet, a lamp of
this construction being specially suitable for use as a street lamp.
is
u, is the lamp body b, the glass; c, the cover; d, and e, the concentric tubes;
9, the reflector; h, the chamber formed by the lamp body a, and the outer
tube ei, cover to samej, j, air inlets; k, k, the air inlets in the outer tube e; u,
the gas supply pipe which I use in this arrangement instead of a coil as herein-
before described between the inner tube d, and the gas pipe u, I provide an
additional pipe d', the space between the two tubes forming the chimney; and the
space between the tube d¹, and the gas pipe u, forming the heated air chamber
corresponding with the chamber in the arrangement herein before described and
shewn in Figures 1, to 4. In this arrangement a ring, or an argand or other
suitable burner or burners e; circular burner of the kind shewn in the drawing and
marked v may be employed; el, is an earthenware or metal continuation of the
tube d', such tube e¹, being perforated if found desirable for causing a portion of
the healed air to be more equally supplied to the interior surface of the flame.

page_text: The action of this lamp will be understood without further description it being
substantially the same as that of the lamp herein before described and shewn in
Figures 1 to 4.
The arrows shew the direction of the passage of the air which as will be seen by
the arrows is supplied in a heated state to the interior surface of the flame. If
the gas is to be carburetted the supply pipe u, passes through a carburetter placed
in any convenient position.
In cases where it is not required to carburet and heat the gas before burning,
the gas may be supplied from below instead of from above as hereinbefore
described and shewn.
Having thus described my said Invention and the best means with which I am
acquainted for carrying the same into effect I would have it understood that I do
not confine myself to the précise details herein laid down and shewn in the
Drawing as the same may be varied without departing from the peculiar
character of my Invention but what I do claim is :
-
Firstly. The general arrangement and construction of the improved lamp
bereinbefore described and represented in Figures 1 to 4 of the accompanying
.Drawing.
Secondly. The modified construction of lamp hereinbefore described and repre-
sented in Figures 5 and 6 of the accompanying Drawing.
Thirdly. The method of supplying heated air to the inner surface of the flame
by causing such air to pass through the chimney in its passage to the flame
substantially as hereinbefore described and represented in Figures 5, and 6, of the
accompanying Drawing.
Fourthly. The employment of the perforated continuation e¹ from the chimney
for distributing the heated air over the interior surface of the flame as hereinbefore
described and represented in Figure 5, of the accompanying Drawing.
In witness whereof I the said Frank William Clark have hereto set
my hand and seal this Thirtieth day of December in the year of our
Lord one thousand eight hundred and eighty one.
FRANK W. CLARK. (L.S.)

page_text: This Specification was, upon the 14th day of December, 1886, amended under
Sections 18 to 21 of the Patents, Designs, and Trade Marks Act, 1883.
LETTERS PATENT to Frank William Clark, of Millbank Street, in the City of
Westminster, Engineer, for an Invention of "LMPROVEMENTS IN RAILWAY
CARRIAGE, STREET, AND OTHER GAS LAMPS OR LANTERNS, THE IMPROVEMENTS
BEING ALSO APPLICABLE TO OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frank William Clark at the
Office of the Commissioners of Patents on the 1st July 1881.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY CARRIAGE, STREET AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed; by my improved
construction of lamp the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows:
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them-the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below the outer tube which serves for the inlet of the air into a chamber
formed by the body of the lamp and the herein before described tubes and suitably
closed; from this chamber the air previously heated in its passage between the two
tubes is conveyed by a pipe or pipes to the gas burner or burners or gas flame or
flames, the said pipe or pipes passing either outside or inside the gas flame or
flames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement hereinbefore described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank William Clark in the Great Seal Patent Office on the
31st December 1881.
FRANK WILLIAM CLARK of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY-CARRIAGE, STREET, AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed; by my improved
construction of lamp, the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows
-
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them; the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below (or only above) the outer tube, which serves for the inlet of the air into
chambers formed by the body of the lamp and the hereinbefore described tubes,
and suitably closed; from these chambers the air previously heated in its passage
between the two tubes and case or body is conveyed to the gas burner or burners
or gas flame or flames, the said hot air passing either outside or inside the gas flame
or flames as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement herein before described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating
purposes.
In order to make my Invention better understood I will now describe the same
by reference to the accompanying Drawing in which Figure 1, is a side elevation,
and Figure 2, a vertical section of a lamp or lantern constructed according to my
Invention and suitable for lighting a railway carriage; Figure 3, is a plan and
Figure 4, is a horizontal section of the same; Figure 5, is a vertical section of a
lamp in which the inner concentric tube serves for the air inlet, and Figure 6, is a
horizontal section on line A, B, of Figure 5. Similar letters of reference in all the
Figures represent similar or corresponding parts.
the
I will first describe the railway carriage lamp shewn in Figures 1, 2, 3, and 4.
a, a, is the case forming the lamp body; b, the usual glass of the same; c,
cover; d and e, are the two concentric tubes with a space f, (forming a chamber)
between them; the inner tube d, forms the chimney and extends above the outer
tube e, as shewn ; these tubes d, and e, are connected together at the bottom by the

page_text: reflector g, and at top by the cover c; h, is the chamber formed by the lamp body a,
and the outer tube e; i, cover to the same with inlet tubes jj, for admitting air
and which are provided with any suitable arrangement to allow of their being
more or less opened or closed so as to regulate the quantity of air supplied to suit
different qualities of gas and the size of the burner; k, k, are air inlet openings in
the outer tube e, also provided with means of regulating the supply of air; to
secure an air tight joint between the lamp case and the cover i, I provide the body a,
with an inclined flange l, on which is screwed by the ring m, an india rubber
washer n; so that when the cover i, is dropped into its place the inner part of the
upper surface of the washer always bears against the under surface of the cover i,
the weight of the cover inflecting the rubber so that even if the cover i, jumps, the
india rubber rises being in tension and follows the movements of the cover i, thus
keeping the joint air tight; o, is the ordinary spring fastening of the lamp; p, the
usual handle; y, is the hinge which is screwed to the flanger, on the lamp body a;
the hinge, serves as the inlet for the gas which. enters at s, and passes through
the tube t, and through the cover c, into the coiled pipe u, shewn placed between
the tubes d, and e, but the said coil may also be placed in the chimney or in any
other suitable position; the coil u, conducts the gas to the burner u, by the tube w;
, a, are tubes for conducting heated air from the chamber to near the point of
ignition; y, y, is an opening between the reflector g, and the lamp body a, through
which air passes from the chamber h, around the glass b, thereby preventing the
glass from becoming too hot, the said air at the same time becomes warmed before
passing to the flame or flames; z, is a muffler or wind guard of any suitable con-
struction; a', is a tapered tube within the chimney to prevent down draught.
The action of the improved lamp is as follows:-
The gas entering through the inlet pipe t, passes into the coil u, and thence to the
burner by the pipe w; upon the gas being ignited a draught is formed in the
chimney, and the air will enter the lamp through the inlets k, and j, and will pass
into the chambers f, and h; the air which passes through the chamber, becomes
heated in its passage and passes in the heated state to the flame through the
tubes x, x; the air from the chamber h, passes through the opening y, and around the
glass b, and under the reflector g, and serves to keep the glass b, and reflector 9,
from becoming too hot, the said air itself thereby becoming warmed before it.
reaches the flame.
From this construction and arrangement of- lamp it will be understood that the
gas before it reaches the burner will be heated by passing through the coil in the
hot air chamber f, and the air for the combustion being also heated, a more
economical light will be obtained.
In cases where it is required to enrich the gas before it passes to the burner, it
may be caused to pass through a suitable carburetter conveniently placed in the
hot air chamber f.
In Figures 5 and 6 of the Drawing I have shewn the arrangement of lamp
I prefer to adopt when the inner concentric tube serves for the air inlet, a lamp of
this construction being specially suitable for use as a street lamp.
;
a, is the lamp body; b, the glass; c, the cover; d, and e, the concentric tubes;
g, the reflector; h, the chamber formed by the lamp body a, and the outer
tube e; i, cover to same; j, j, air inlets; k, k, the air inlets in the outer tube e; u, is
the gas supply pipe which I use in this arrangement instead of a coil as herein-
before described; between the inner tube d, and the gas pipe u, I provide an
additional pipe d', the space between the two tubes forming the chimney and the
space between the tube d¹, and the gas pipe u, forming the heated air chamber
corresponding with the chamber f, in the arrangement herein before described and
shewn in Figures 1, to 4. In this arrangement a ring, or an argand or other
suitable burner or burners v, may be employed; e', is an earthenware or metal
continuation of the tube d¹, such tube e¹, being perforated if found desirable for
causing a portion of the heated air to be more equally supplied to the interior
surface of the flame.

page_text: The action of this lamp will be understood without further description it being
substantially the same as that of the lamp hereinbefore described and shewn in
Figures 1 to 4.
The arrows shew the direction of the passage of the air which as will be seen by
the arrows is supplied in a heated state to the interior surface of the flame. If
the gas is to be carburetted the supply pipe u, passes through a carburetter placed
in any convenient position.
In cases where it is not required to carburet and heat the gas before burning,
the gas may be supplied from below instead of from above as hereinbefore
described and shewn.
My improvements are partly applicable to stoves and furnaces for heating
purposes as will be understood without further description.
Having thus described my said Invention and the best means with which I am
acquainted for carrying the same into effect I would have it understood that I do
not confine myself, to the precise details herein laid down and shewn in the
Drawing as the same may be varied without departing from the peculiar
character of my Invention but what I do claim is :-
Firstly. The general arrangement and construction of the improved lamp
hereinbefore described and represented in Figures 1 to 4 of the accompanying
Drawing.
Secondly. The modified construction of lamp hereinbefore described and repre-
sented in Figures 5 and 6 of the accompanying Drawing.
Thirdly. In a railway carriage or other lamp I claim the method of heating the
air before it reaches the flame by enusing it to pass between concentric tubes
arranged and operating substantially as hereinbefore described and represented-in
the accompanying Drawing.
Fourthly. The method herein described of forming the joint between the lamp
body and cover by the employment of a rubber ring in combination with an
inclined flange substantially as and for the purposes hereinbefore described and
represented in Figures 1, and 5, of the necompanying Drawing.
Fifthly. Thirdly The method of supplying heated air to the inner surface of the
flame by causing such air to pass through the chimney in its passage to the flame
substantially as hereinbefore described and represented in Figures 5, and 6, of the
accompanying Drawing.
Sixthly Fourthly The employment of the perforated continuation of e¹ from the
chimney for distributing the heated air over the interior surface of the flame as
hereinbefore described and represented in Figure 5, of the accompanying Drawing.
In witness whereof I the said Frank William Clark have hereto set
my hand and seal this Thirtieth day of December in the year of our
Lord one thousand eight hundred and eighty one.

page_text: LETTERS PATENT to Frank William Clark, of Millbank Street, in the City of
Westminster, Engineer, for an Invention of IMPROVEMENTS IN RAILWAY
CARRIAGE, STREET. AND OTHER GAS LAMPS OR LANTERNS THE IMPROVEMENTS
"
PROVISIONAL SPECIFICATION left by the said Frank William Clark at the
Office of the Commissioners of Patents on the 1st July 1881.
FRANK WILLIAM CLARK, of Millbank Street, in the City of Westminster,
Engineer. "IMPROVEMENTS IN RAILWAY CARRIAGE, STREET, AND OTHER GAS
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street,
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed; by my improved
construction of lamp the gas to be burned is itself also heated before it reaches the.
point of ignition.
A suitable arrangement for carrying out my Invention is as follows:-
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them; the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below the outer tube which serves for the inlet of the air into a chamber
formed by the body of the lamp and the hereinbefore described tubes, and suitably
closed; from this chamber the air previously heated in its passage between the two
tubes is conveyed by a pipe or pipes to the gas burner or burners or gas flame or
flames, the said pipe or pipes passing either outside or inside the gas flame or
flames, as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes, so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement hereinbefore described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating
purposes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank William Clark in the Great Seal Patent Office on the
31st December 1881.
"
OTHER GAS
FRANK WILLIAM CLARK, of Millbank Street, in the City of Westminster,
Engineer. IMPROVEMENTS IN RAILWAY-CARRIAGE, STREET, AND
LAMPS OR LANTERNS, THE IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER
PURPOSES."
This Invention relates to an improved construction of railway carriage, street,
and other gas lamps or lanterns where heated air is introduced in sufficient
quantities to supply the flame or flames so as to produce more perfect combustion
than hitherto, the quantity of heated air introduced being easily regulated
according to the quality and quantity of the gas to be consumed; by my improved
construction of lamp the gas to be burned is itself also heated before it reaches the
point of ignition.
A suitable arrangement for carrying out my Invention is as follows :—
The lamp or lantern body is formed of a suitable case to which I adapt two
concentric tubes of suitable section with a space between them, the inner tube
which forms the chimney for carrying off the products of combustion extends above
and below (or only above) the outer tube which serves for the inlet of the air into
chambers formed by the body of the lamp and the hereinbefore described tubes,
and suitably closed; from these chambers the air previously heated in its passage
between the two tubes and case or body is conveyed to the gas burner or burners
or gas flame or flames, the said hot air passing either outside or inside the gas flame
or flames, as required.
The gas is supplied to the burner or burners by a coiled pipe within the said
chamber or between the two tubes, so that the gas also becomes heated in its
passage through the coil to the burner or burners.
Instead of the arrangement herein before described it will be evident that the
inner tube may be arranged to serve for the air inlet and the space between the
two tubes for the chimney.
My improvements are also applicable to stoves and furnaces for heating
purposes.
In order to make my Invention better understood, I will, now describe the same
by reference to the accompanying Drawing, in which Figure 1 is a side elevation
and Figure 2 a vertical section of a lamp or lantern constructed according to my
Invention and suitable for lighting a railway carriage. Figure 3 is a plan, and
Figure 4 is a horizontal section of the same. Figure 5 is a vertical section of a
lamp in which the inner concentric tube serves for the air inlet, and Figure 6 is a
horizontal section on line A, B, of Figure 5. Similar letters of reference in all the
Figures represent similar or corresponding parts.
I will first describe the railway carriage lamp shewn in Figures 1, 2, 3, and 4.
a, a, is the case forming the lamp body; b, the usual glass of the same; c,
the
cover; d and e are the two concentric tubes with a space f (forming a chamber)
between them. The inner tube & forms the chimney and extends above the outer
tube e, as shewn; these tubes d and e are connected together at the bottom by the
reflector g and at top by the cover c; h is the chamber formed by the lamp body a
and the outer tube e; i, cover to the same with inlet tubes j, j, for admitting air,
and which are provided with any suitable arrangement to allow of their being
more or less opened or closed, so as to regulate the quantity of air supplied to suit
different qualities of gas and the size of the burner; k, k, are air inlet openings in
the outer tube e also provided with means of regulating the supply of air. To

page_text: secure an air tight joint between the lamp case and the cover i I provide the body a
with an inclined flange on which is screwed by the ring m an india rubber
washer n, so that when the cover i is dropped into its place the inner part of the
upper surface of the washer always bears against the under surface of the cover i,,
the weight of the cover inflecting the rubber so that even if the cover i jumps the
india rubber rises, being in tension, and follows the movements of the cover i, thus
keeping the joint air tight; o is the ordinary spring fastening of the lamp; 2, the
usual handle; q is the hinge which is screwed to the flange r on the lamp body a.
The hinge q serves as the inlet for the gas which enters at s, and passes through
the tube t and through the cover c into the coiled pipe u, shewn placed between
the tubes & and e, but the said coil may also be placed in the chimney or in any
other suitable position. The coil u conducts the gas to the burner v by the tube w;
x, x, are tubes for conducting heated air from the chamber f to near the point of
ignition; y, y, is an opening between the reflector g and the lamp body a through
which air passes from the chamber h around the glass b, thereby preventing the
glass from becoming too hot, the said air at the same time becomes warmed before
passing to the flame or flames; z is a muffler or wind guard of any suitable con-
struction; a' is a tapered tube within the chimney to prevent down draught.
The action of the improved lamp is as follows:-
The gas entering through the inlet pipet passes into the coil u and thence to the
burner by the pipe w; upon the gas being ignited a draught is formed in the
chimney, and the air will enter the lamp through the inlets and j and will pass
into the chambers f and h; the air which passes through the chamber ƒ becomes
heated in its passage and passes in the heated state to the flame through the
tubes x, x; the air from the chamber / passes through the opening y and around the
glass b, and under the reflector g, and serves to keep the glass b and reflector g
from becoming too hot, the said air itself thereby becoming warmed before it
reaches the flame.
From this construction and arangement of lamp it will be understood that the
gas before it reaches the burner will be heated by passing through the coil in the
hot air chamber f, and the air for the combustion being also heated a more
economical light will be obtained.
In cases where it is required to enrich the gas before it passes to the burner, it
may be caused to pass through a suitable carburetter conveniently placed in the
hot air chamber f.
In Figures 5 and 6 of the Drawing I have shewn the arrangement of lamp
I prefer to adopt when the inner concentric tube serves for the air inlet, a lamp of
this construction being specially suitable for use as a street lamp.
a is the lamp body; b, the glass; c, the cover; d and e, the concentric tubes;
g, the reflector; h, the chamber formed by the lamp body a and the outer
tube e; i, cover to same; j, j, air inlets; k, l, the air inlets in the outer tube e; u is
the gas supply pipe which I use in this arrangement instead of a coil, as herein-
before described; between the inner tube d and the gas pipe u I provide an
additional pipe d', the space between the two tubes forming the chimney, and the
space between the tube and the gas pipe u forming the heated air chamber
corresponding with the chamber in the arrangement hereinbefore described and
shewn in Figures 1 to 4. In this arrangement a ring or an argand or other
suitable burner or burners may be employed; e¹ is an earthenware or metal
continuation of the tube d', such tube e¹ being perforated if found desirable for
causing a portion of the heated air to be more equally supplied to the interior
surface of the flame.
The action of this lamp will be understood without further description, it being
substantially the same as that of the lamp herein before described and shewn in
Figures 1 to 4.
The arrows shew the direction of the passage of the air which, as will be seen by
the arrows, is supplied in a heated state to the interior surface of the flame.
If

page_text: the gas is to be carburetted the supply pipe u passes through a carburetter placed
in any convenient position.
In cases where it is not required to carburet and heat the gas before burning,
the gas may be supplied from below instead of from above, as herein before
described and shewn.
My improvements are partly applicable to stoves and furnaces for heating
purposes as will be understood without further description.
Having thus described my said Invention and the best means with which I am
acquainted for carrying the same into effect, I would have it understood that I do
not confine myself to the precise details herein laid down and shewn in the
Drawing, as the same may be varied without departing from the peculiar
character of my Invention, but what I do claim is,―
Firstly. The general arrangement and construction of the improved lamp
hereinbefore described and represented in Figures 1 to 4 of the accompanying
Drawing.
Secondly. The modified construction of lamp hereinbefore described and repre-
sented in Figures 5 and 6 of the accompanying Drawing.
Thirdly. In a railway carriage or other lamp, I claim the method of heating the
air before it reaches the flame by causing it to pass between concentric tubes
arranged and operating substantially as hereinbefore described and represented in
the accompanying Drawing.
Fourthly. The method herein described of forming the joint between the lamp
body and cover by the employment of a rubber ring in combination with an
inclined flange, substantially as and for the purposes hereinbefore described and
represented in Figures 1 and 5 of the accompanying Drawing.
Fifthly. The method of supplying heated air to the inner surface of the flame by
causing such air to pass through the chimney in its passage to the flame,
substantially as herein before described and represented in Figures 5 and 6 of the
accompanying. Drawing.
Sixthly. The employment of the perforated continuation of the chimney for
distributing the heated air over the interior surface of the flame, as herein before
described and represented in Figure 5 of the accompanying Drawing.
In witness whereof, I, the said Frank William Clark, have hereto set
my hand and seal, this Thirtieth day of December in the year of our
Lord One thousand eight hundred and eighty one.