IMPROVEMENTS IN SMOKE-CONSUMING FURNACES
Year: 1861

page_text: LETTERS PATENT to Charles Stevens, of 31, Charing Cross, in the County
of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
SMOKE-CONSUMING FURNACES."-A communication from abroad by Antoine
Léonide Lacroix, of 42, Rue Laffitte, Paris, in the Empire of France.
Sealed the 13th December 1861, and dated the 20th June 1861.
PROVISIONAL SPECIFICATION left by the said Charles Stevens at the
Office of the Commissioners of Patents, with his Petition, on the 20th
June 1861.
I, CHARLES STEVENS, of 31, Charing Cross, in the County of Middlesex,.
Patent Agent, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN SMOKE-CONSUMING FURNACES," & that it is a communication to
me from abroad by Antoine Léonide Lacroix, of 42, Rue Laffitte, Paris, in
the Empire of France, to be as follows:-
My Invention consists in a pecular arrangement given to the brick separa-
tion which divides the fire-boxes of two boilers; no extra expense is necessitated
in placing it, economy is even effected, in that the solid mass of fire-brick which
separates the two fire-boxes is made hollow; by this arrangement the smoke
is entirely consumed, and a saving of thirty per cent. realised in the combustable.
The furnace is constructed as follows:-Two grates are placed opposite
each other beneath the boiler tubes; rectangular openings are made in the
horizontal plan of the grates, which allow a communication from the two fire-

page_text: boxes to a third placed in the middle of them; this third compartment is the
smoke consumer, and is itself divided into compartments corresponding with the
openings above mentioned, the number of which depends on the length of the
grates.
Small separations perpendicular to the longitudinal axis of the furnace
divide the smoke-consuming department, but are only half the height of the
space which separates the grate from the boiler tubes, in order to allow a free
space in the upper part, which causes the products of the combustion to pass
in the flue placed in the upper part of the fire bridge.
The direction taken by the flames is as follows:-The air passing through
the grate is partly burnt and ascends to the upper part, heats the boiler tubes,
and not finding escape descends by the lower openings above-mentioned.
These openings of the grates being opposite to each other, the flames unite in
the smoke consumer, and produce a combustion of all the volatile products.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Stevens in the Great Seal Patent Office on the
20th December 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
STEVENS, of 31, Charing Cross, in the County of Middlesex, Patent Agent,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of June, in the year of our Lord One
thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Charles Stevens, Her special licence that I, the said Charles
Stevens, my executors, administrators, and assigns, or such others as I, the
said Charles Stevens, 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 SMOKE-CONSUMING FURNACES," a communication to
me from abroad by Antoine Léonide Lacroix, of 42, Rue Laffitte, Paris, in
the Empire of France, upon the condition (amongst others) that I, the
said Charles Stevens, my executors or administrators, by an instrument in
writing under my, or their, or one of their bands and seals, should particularly

page_text: 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 Charles Stevens, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, that is to say :-
My Invention relates to improvements in furnaces by the application of
which the smoke is entirely consumed, an economy of 30 °/° is effected in the
combustible, and from the simplicity of the construction the furnaces last
considerable longer, and the improvements can be easily adapted to existing
furnaces. The improved system differs essentially from all the arrangements
bitherto known, in that none of its parts are of metal, it consisting simply in
the arrangement of the brick partition which separates the fire-boxes of the two
boilers. No extra expense is incurred in fitting it, a saving is even effected,
the solid mass of brickwork generally separating the two fire-boxes being in
the present system converted into a hollow compartment.
The improved furnace is constructed of two grates placed opposite and
beneath the boilers rectangular openings 12 inches long by 4 inches high
are made in the horizontal plan of the grates, allowing the divisions of the
two fire-boxes to communicate with a third compartment, which is situated
between them and in which the smoke is consumed. This third compartment
or smoke consumer is divided into other compartments corresponding with the
openings made in the grates as above-mentioned, the number of which must
depend on the length of the grate. The small divisions perpendicular to the
longitudinal axis of the furnace, and serving to separate the smoke consumer
into compartments, are only about half the height of the space which separates
the grate from the boilers, thus allowing a free space above by which the
products of the combustion are conducted into the flue placed at upper part
of the fire-bridge of the furnace.
The course taken by the flames is as follows:-The air passes through the
grate, is partly burnt, it then ascends and heats the boilers, and finding no
escape descends and escapes by the openings above mentioned, which being
opposite each other the flames on both sides become united in the smoke
consumer. It is by thus uniting that the volatile products are consumed, and
to effect this it is necessary that the grates be fed alternately so that only one
of the fire-boxes contains fresh coal at a time, the coal being in the other
almost or entirely converted into coke.

page_text: Having thus described my Invention, what I claim and desire to secure by
Letters Patent is the introduction of a smoke-consuming compartment
between the two fire-boxes in the manner and for the purposes herein-before
described.
In witness whereof, I, the said Charles Stevens, have hereunto set my
hand and seal, this Twentieth day of December, in the
Lord One thousand eight hundred and sixty-one.
year of our
CHARLES STEVENS. (L.S.)