IMPROVEMENTS IN APPARATUS FOR THE PREVENTION OF SMOKE IN FURNACES
Year: 1869

page_text: LETTERS PATENT to James Foster, of Bury, in the County of
Lancaster, and John Hollinrake, of the same Place, for the
Invention of "IMPROVEMENTS IN APPARATUS FOR THE PREVENTION OF
SMOKE IN FURNACES."
COMPLETE SPECIFICATION filed by the said James Foster and John
Hollinrake at the Office of the Commissioners of Patents, with their
Petition and Declaration, on the 10th June 1869, pursuant to the
9th Section of the Patent Law Amendment Act, 1852.

page_text: WHEREAS we are in possession of an Invention for "IMPROVEMENTS IN
APPARATUS FOR THE PREVENTION OF SMOKE IN FURNACES," and have petitioned
Her Majesty to grant unto us, our executors, administrators, and
assigns, Her Royal Letters Patent for the same, and have made solemn
Declaration that we are the true and first Inventors thereof.
NOW KNOW YE, that we, the said James Foster and John Hollinrake,
do hereby declare that the following Complete Specification, under our
hands and seals, fully describes and ascertains the nature of the said
Invention, and in what manner the same is to be performed, in and by
the following statement (that is to say):-
Our improvements consist in making a sufficient number of the grate
bars in steam boiler or other furnaces of such a depth that they shall
protrude above the fuel lying on the other grate bars, so as to admit
air to the gases evolved from the fuel, and thereby improve the com-
bustion of the said gases, so as to prevent the formation of smoke.
These deep bars are placed side by side either the whole length of the
grate or any required portion of that length, and the number of deep
bars used will depend on the area of the open space for admitting
the air from the ash-pit to the interior of the fire chamber above the
fuel, and also on the area of the fire-grate requiring from about four
to six square inches of area of spaces between the deep bars per
square foot of grate, so that a sufficient quantity of air may be supplied
through them to facilitate the combustion of the gases and prevent the
formation of smoke. The depth of the bars may vary from about four
inches to twelve inches above the grate, depending on the mode of
firing, but generally they will be of such a depth as to stand above
the other grate bars about six inches, and may be placed in several
groups if required, but we prefer to place them near the middle of the
fire-grate.
Having now described the nature of our said Invention and the
manner in which the said Invention is to be performed, we wish it to
be understood that what we claim as of our Invention is, the use and
manufacture of grate bars of such increased depth that they when placed
in the furnace shall protrude or project above the grate that carries
the fuel so as to admit air to the censos aralred from the
1

page_text: improving the combustion and preventing the formation of smoke, as
herein described.
In witness whereof, we, the said James Foster and John Hollinrake,
have hereunto set our hands and scals, this Ninth day of June,
in the year of our Lord One thousand eight hundred and sixty-
nine.
JAMES FOSTER.
(L.S.)
Witness,
THOMAS BALDWIN,
Engineer,
Bury,
JOHN HOLLINRAKE. (L.S.)
Lancashire.