IMPROVEMENTS IN EFFECTING THE COMBUSTION OF FUEL AND THE CONSUMPTION OF SMOKE IN STEAM BOILER AND OTHER FURNACES
Year: 1855

page_text: LETTERS PATENT to James Peter Lark, of Nine Elms Lane, Vauxhall,
in the County of Surrey, Foreman to Messrs. Francis, Brothers, of the
same Place, Cement Manufacturers, for the Invention of "IMPROVEMENTS
IN EFFECTING THE COMBUSTION OF FUEL AND THE CONSUMPTION OF SMOKE IN
STEAM BOILER AND OTHER FURNACES."
PROVISIONAL SPECIFICATION left by the said James Peter Lark at
the Office of the Commissioners of Patents, with his Petition, on the
15th January 1855.
I, JAMES PETER LARK, of Nine Elms Lane, Vauxhall, in the County of
Surrey, Foreman to Messieurs Francis, Brothers, of the same Place, Cement
Manufacturers, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN EPPECTING THE COMBUSTION OF FUEL AND THE CONSUMPTION OF SMOKE
IN STEAM BOILER AND OTHER FURNACES" to be as follows:-
The Invention consists in causing air admitted to furnaces above the fire
bars to pass in numerous streams through a chamber containing ignited fuel,
by which it becomes highly heated before passing into the furnace, with the
use of a jet or jets of steam admitted behind the furnace bridge, or at the
back end of the furnace, where it is caused to combine with heated air;

page_text: and also in forming the fire bars in two lengths, the hinder portion being
shorter than the front, and 'the spaces between such hinder bars being wider,
so as to admit more air to pass between them than between the front portions
of the said bars.
The chamber for the reception and combustion of fuel for heating the air
passing into the furnace I form on the inside of the fire door, and through the
back and front of such chamber I form numerous holes for the passage of air,
which thereby becomes highly heated in passing through the burning fuel in
such chamber to the furnace; but I do not confine myself to applying such
chamber to the fire door, so long as air is caused to pass to the furnace in
numerous streams through a chamber containing ignited fuel. The steam is
conducted amongst the heated air supplied to the back end of the furnace by
suitable pipes; and I prefer that the length of the hinder portion of the fire
bars be about one-third that of the front bars.
pursuance
ULIC
by the said James Peter Lark in the Great Seal Patent Office on the
14th July 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
PETER LARK, of Nine Elms "Lane, Vauxhall, in the County of Surrey,
Foreman to Messrs. Francis, Brothers, of the same Place, Cement Manu-
facturers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of January, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Peter Lark, Her special licence that I, the said James Peter Lark,
my executors, administrators, and assigns, or such others as I, the said James
Peter Lark, 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, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN EFFECTING THE
COMBUSTION OF FUEL AND THE CONSUMPTION OF SMOKE IN STEAM BOILER AND OTHER
FURNACES," upon the condition (amongst others) that I, the said James Peter
Lark, by an instrument in writing under my hand and seal, should par-
ticularly describe and ascertain the nature of the said Invention, and in what

page_text: 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.
41
18
NOW KNOW YE, that I, the said James Peter Lark, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof (that is to say):-
The Invention relates to a mode of supplying air to furnaces above the fire
bars, by causing it to pass in numerous streams through a chamber containing
ignited fuel, by which it becomes highly heated before passing into the
furnace. The Invention also relates to a mode of supplying a jet or jets of
steam behind the furnace bridge, or at the back end of the furnace, in com
bination with heated air. The Invention also relates to forming the fire bars
in two lengths, the hinder portion being shorter than the front, and the spaces
between such hinder bars being wider, so as to admit more air to pass between
them than between the front portions of the said bars.
.
1+
The chamber for the reception and combustion of fuel for heating the air
passing into the furnace I form on the inside of the fire door, or in other con-
venient situation, and through the back and front of such chamber I form
numerous holes for the passage of air, which thereby becomes highly heated
in passing through such chamber to the furnace. The steam is conducted
amongst the heated air supplied to the back end of the furnace by suitable
pipes, and the fire bars are arranged as herein-after.described.
In order that the nature of my said Invention; and the means which I
adopt in carrying the same into effect, may be fully understood, I will proceed
to describe the Drawings annexed:
:
DESCRIPTION OF THE, DRAWINGS....
Figure 1 shows a longitudinal section, Figure 2 a plan in section, Figure 3
an end view, and Figures 4 and 5 other views, of a steam boiler furnace with
my improvements applied. a is the fire door for the supply of fuel to the fire-
place; it has an internal plate (1), which, with the door itself, is perforated
with numerous holes, so as to admit through it numerous streams of air to aid
the combustion of the fuel on the fire bars, somewhat as has heretofore been
practised. But in carrying out my improvements, I form the space between
the door a and the plate (1) into a chamber a¹ for the reception and combus-
tion of fuel, there being bars (2) by which such fuel is supported in the
chamber a. The air passing into the furnace through the door is thus caused
to pass through a chamber of ignited fuel, by which it becomes highly heated

page_text: before passing amongst the fuel on the fire bars, and the consumption of the
products of combustion without producing smoke is thereby greatly facilitated.
b is a pipe conveying steam from the boiler, for the purpose herein-after
explained.
The fire bars to the furnace are divided into two parts, c and d; those forming
the hinder portion d being shorter than the front portion c, and the spaces
between the bars & being wider, so as more freely to admit of air passing
between them than between the bars of the front portion c. e is the furnace
bridge, behind which are a series of fire bricks e', placed so as to leave spaces e
between them for the passage of heated air up from the chamber fand that
conveyed by the pipe 9,. as also for jets of steam from the pipes in connec-
tion with the steam pipe b. The air admitted from the chamber f is supplied
to that chamber from the passages f¹ (one or more on each side of the furnace),
by which the air in passing to the chamber f through the openings f² becomes
heated. Upon these openings f, f, are placed regulators, to regulate the
amount of air admitted through the openings f to the chamber f. I also form
chambers opposite the edges or sides of the chamber a', with communications
therefrom by channel f to the passages f¹, when, by perforating those parts of
the chamber a¹ next the chamber f³, heated air will also pass from the-chamber
a to the passages f¹, thence by the chamber f to the back of the furnace.
Steam is also admitted to the passages f¹ by the pipes 63 from the pipe b.
The air supplied by the pipe 7 is fed from the interior of the fire-place, there
being openings therefrom through the plate h to chambers h¹ (one on each side
of the furnace), and thence by the passages i to the fan or blower j, by which
such air is forced forwards through the pipe g. Motion is communicated to
the axis of the fan or blower from a steam engine or other suitable power by 'a
strap or band acting upon the pulley affixed to the axis k¹, which turns in
suitable bearings, as shown, and has affixed to it the bevilled pinion k, which
takes into and drives the bevilled pinion upon the axis l, upon which is
affixed the bevilled pinion 2, which takes into and drives the bevilled pinion m
upon the axis m³, upon which is affixed the bevilled pinion m² which takes into
and drives the pinion n upon the axis of the fan or blower. The heated air
thus caused to pass up in divided streams, combined with jets of steam at the
back end of the furnace, is introduced among the products of combustion, and
facilitates their consumption. In some cases, especially where small furnaces
are used, as in the heating of ovens or kilns, I omit the use of the heated air
as withdrawn from the fire-place and propelled by the fan or blower j, but I
then employ a closed ash-pit.
l
Having thus described the nature of my said Invention, and the best means

page_text: I am acquainted with for carrying the same into effect, I would have it under-
stood that what I claim as the Invention, whereof the exclusive use is intended
to be secured by the said Letters Patent, is,-
First, the supplying to furnaces in small streams or jets, air heated by
passing through a chamber containing ignited fuel, as above described.
Secondly, the constructing the fire bars of two portions, whereof one is
shorter and with wider spaces between the bars than the other, as above
described.
Thirdly, the supplying steam in combination with heated air in streams or
jets at the back end of the furnace, as above described.
In witness whereof, I, the said James Peter Lark, have hereunto set my
hand and seal, this Fourteenth day of July, in the year of our Lord
One thousand eight hundred and fifty-five.
5 Witness,
J. R. TAYLER,
28, Great James Street.
JAMES PETER LARK. (L.G.)