IMPROVEMENTS IN THE CONSTRUCTION OF BRIDGES OF THE FURNACES OF MARINE AND CORNISH. BOILERS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER KINDS OR FURNACES
Year: 1882

page_text: LETTERS PATENT to Christopher Hill, of Blaydon-on-Tyne, in the County of
Northumberland, Engineer, for an Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF BRIDGES OF THE FURNACES OF MARINE AND CORNISH.
BOILERS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE TO OTHER KINDS
OR
FURNACES"
PROVISIONAL SPECIFICATION left by the said Christopher Hill at the
Office of the Commissioners of Patents on the 4th August 1882.
CHRISTOPHER HILL, of Blaydon-on-Tyne, in the County of Northumberland,
Engineer, "IMPROVEMENTS IN THE CONSTRUCTION OF BRIDGES OF THE FURNACES
OF MARINE AND CORNISH BOILERS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE
TO OTHER KINDS OF FURNACES,"
This Invention consists in improvements in the construction of bridges employed
in the furnaces of marine and Cornish boilers, such improvements being also
applicable to other kinds of furnaces in which bridges or other analogous or
similar contrivances are used. By means of the said improvements heat is
generated in less time and more perfectly than is the case when bridges constructed'
in the ordinary manner are employed, and owing to a current of heated air being
brought, as hereinafter described, into contact with the fuel complete combustion
and consequently great economy of fuel are effected, whilst at the same time the
escape of smoke is entirely, or nearly so, avoided.
The bridge, which is arranged at the end of the grate, in the ordinary manner,
is formed of bricks, wrought iron, cast iron or any other suitable material, and is
made hollow. Air is admitted into the hollow portion of the bridge through an
opening formed in the front thereof below the fire bars, and such air passing
upwards through the hollow bridge escapes through an opening or openings,
formed in the latter above the fire bars, on to the fuel It will be readily under-
stood that the air, in its passage through the ash pit and hollow bridge, becomes
thoroughly heated, so that on coming into contact with the fuel on the grate and
meeting the other currents of air, it will effect a complete combustion beneath
the crown of the furnace, whilst at the same time the current of air so conducted
will keep the fire from the bridge and assist in preventing the formation of
clinkers.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Christopher Hill in the Great Seal Patent Office on the
31st January 1883.
"s
CHRISTOPHER HILL, of Blaydon-on-Tyne, in the County of Northumberland,
Engineer, IMPROVEMENTS IN THE CONSTRUCTION OF BRIDGES OF THE FURNACES
OF MARINE AND CORNISH BOILERS, SUCH IMPROVEMENTS BEING ALSO APPLICABLE
TO OTHER KINDS OF FURNACES,"
My said invention consists in improvements in the construction of bridges
employed in the furnaces of marine and Cornish boilers, such improvements being
also applicable to other kinds of furnaces in which bridges or other analogous or
similar contrivances are used. By means of the said improvements heat is
generated in less time and more perfectly than is the case when bridges constructed
in the ordinary manner are employed, and owing to a current of heated air being
brought, as hereinafter described, into contact with the fuel, complete combustion
and consequently great economy of fuel are effected, whilst at the same time, the
escape of smoke is entirely, or nearly so, avoided.
The bridge, which is arranged at the end of the grate, in the ordinary manner,
is formed of bricks, wrought iron, cast iron, or any other suitable material, and is
made hollow. Air is admitted into the hollow portion of the bridge through an
opening formed in the front thereof below the fire bars, and such air passing
upwards through the hollow bridge escapes through an opening or openings,
formed in the latter above the fire bars, on to the fuel. It will be readily under-
stood that the air, in its passage through the ash pit and hollow bridge, becomes
thoroughly heated, so that on coming into contact with the fuel on the grate, and
meeting the other currents of air, it will effect a complete combustion beneath
the crown of the furnace, whilst at the same time the current of air so conducted
will keep the fire from the bridge and assist in preventing the formation of
clinkers.
I will now proceed to describe the accompanying drawings from which the
nature of my said Invention will be more clearly understood. Figure 1. is a cross
section of a furnace constructed with a bridge formed as herein before described, and
Figure 2. is a longitudinal section, of a furnace of like nature, taken through the
line A.B. in Figure 1. A. is the boiler. B. the hollow bridge of the furnace, b. the
opening in the same below the fire bars, b¹. the opening in the hollow bridge above
the fire bars, and c. are the fire bars.
Having thus described and ascertained the nature of my said Invention and the
manner in which it is to be performed I would observe in conclusion that what I
consider novel and original and therefore claim as constituting the invention
secured to me by the said hereinbefore in part recited Letters Patent, is :-
The construction of a hollow bridge for furnaces, such bridge having an opening,
for the admission of air to the hollow interior, below the fire bars and also an
opening above the fire bars for the escape of air from the interior on to the fuel,
substantially as hereinbefore described and set forth.
In witness whereof I the said Christopher Hill have hereunto set my hand
and seal this seventeenth day of January in the year of our Lord One
thousand eight hundred and eighty three.