IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES
Year: 1870

page_text: LETTERS PATENT to William Thornley, of Little Lever, in the
County of Lancaster, Agent, Samuel Spencer, of Prestolee, in the
same County, Engineer, and Joseph Wright, of Gresford, in the
County of Denbigh, North Wales, Engineer, for the Invention of
PROVISIONAL SPECIFICATION left by the said William Thornley,
Samuel Spencer, and Joseph Wright at the Office of the
Commissioners of Patents, with their Petition, on the 13th January
1870.
We, WILLIAM THORNLEY, of Little Lever, in the County of Lan-
caster, Agent, SAMUEL SPENCER, of Prestolec, in the same County,
Engineer, and JOSEPH WRIGHT, of Gresford, in the County of Denbigh,
North Wales, Engineer, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES," to be as
follows:-
:-
This Invention has for its object improvements applicable to those
descriptions of steam boiler and other furnaces wherein rocking or

page_text: moveable fire bars are used in order to obviate the nuisance arising from
black smoke being emitted from the chimney mouth, and consists in
applying openings or slots formed in the dead plate of such furnaces
for the admission of air on to the top of the fuel lying upon such
descriptions of fire-bars for the better consumption for the fuel, and
further in the application of or opening through the bridge from the
furnace to the back of the bridge, which slot or opening is set at the
proper angle to allow the heated air passing through it to mix with the
products of combustion passing over the bridge in the direction of
the draught, and so as not to impede the draught as is the case when
a current of cold air is admitted through a hollow or slotted bridge at
right angles to the draught in furnaces in which ordinary stationary fire-
bars are used.
The openings in the dead plate are adjustable in size by being
constructed with a sliding gird which allows of their size being regulated
to the greatest nicety so as to suit the area of flue and strength of
draught, which is found to differ in almost every furnace.
These improvements are especially useful when applied in conjunction
with rocking or moveable fire-bars which prevent the air space between
the fire-bars being fitted up, and in combination together constitute a
fuel economising and smoke consuming furnace.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Thornley, Samuel Spencer, and Joseph
Wright in the Great Seal Patent Office on the 13th July 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM 2
THORNLEY, of Little Lever, in the County of Lancaster, Agent, SAMUEL
SPENCER, of Prestolee, in the same County, Engineer, and JOSEPп
WRIGHT, of Gresford, in the County of Denbigh, North Wales, Engineer,.
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her a
Letters Patent, bearing date the Thirteenth day of January, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said William Thornley, Samuel Spencer,

page_text: vend, within the
Channel Islands,
STEAM BOILER AND
and Joseph Wright, Her special licence that we, the said William
Thornley, Samuel Spencer, and Joseph Wright, our exccutors, adminis-
trators, and assigns, or such others as we, the said William Thornley,
Samuel Spencer, and Joseph Wright, our '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
United Kingdom of Great Britain and Ireland, the
and Isle of Man, an Invention for "IMPROVEMENTS IN
OTHER FURNACES," upon the condition (amongst others) that we; the
said William Thornley; Samuel Spencer, and Joseph Wright, our
executors or administrators, by an instrument in writing under our, or
their, or one of their hands and seals, should particularly 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 we, the said William Thornley, Samuel Spencer,
and Joseph Wright, do hereby declare the nature of the said Invention,
and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This Invention has for its object improvements particularly applicable
to those descriptions of steam boiler and other furnaces wherein rocking
or moveable fire-bars are used in order to obviate the nuisance arising
from black smoke being emitted from the chimney mouth, and consists
in applying openings or slots formed in the dead plate of such furnaces
for the admission of air on to the top of the fuel lying upon such
descriptions of fire-bars for the better consumption of the fuel, and
further in the application of a slot or opening through the bridge from
the furnace or ash-pit to the back of the bridge, which slot or opening
may extend the whole width of the bridge and be from three-quarters to
one inch in width according to the size of furnace and strength of
draught in the flue, such slot or opening being set at an angle of from
twenty-five to fifty degrees from the horizon or line of fire-bars, and
thus such slot or opening allows the heated air passing through it to
mix with the products of combustion passing over the bridge in the
direction of the draught and does not impede the draught as when a

page_text: current of cold air is admitted through a hollow or slotted bridge at
right angles to the draught. In some furnaces it may be desirable to
partially or entirely close the slot or opening in the bridge when the
freshly fed fuel has become incandescent. This is effected by mounting
a flap-hinged door beneath the fire-bars at the entrance to the slot or
opening, or at the back of the bridge where the air escapes from such
slot or opening, or a damper may be mounted in the bridge for the
same purpose, such door or damper being opened and closed by a
connecting rod worked by the hand of the fireman, or connected to the
fire-door so as to be opened at the same time as such fire-door and to be
closed by any of the various arrangements of self-acting mechanism
now in use for regulating the admission of air to furnaces. By means
of this door or damper the admission of heated air for mixing with the
products of combustion at the back of the bridge may be regulated and
adjusted.
The openings in the dead plate are made adjustable in size by being
constructed with a sliding grid, which allows of their size being regu-
lated to the greatest nicety, so as to suit the area of flue and strength
of draught, which is found to differ in almost every furnace and cannot
be ascertained beforehand.
་
These improvements are specially useful when applied in conjunction
with rocking or moveable fire-bars which prevent the air space between
the fire-bars being filled up, but these improvements are also applicable
to furnaces wherein stationary fire-bars are used.
Having thus particularly described and ascertained the nature of
this our said Invention, together with the best methods with which
wc are acquainted for carrying the same into practical effect, we wish it
to be distinctly understood that we claim,-
1st. The use and application to steam boiler and other furnaces of a
sliding grid mounted over slots or openings formed in the dead plate to
regulate the admission of air in accordance with the area of flue and
strength of draught in such furnace, as and for the purpose described.
2nd. The use and application of a slot or opening in the bridge of
steam boiler and other furnaces set an angle of from twenty-five to
fifty degrees with the horizon or line of fire-bars and capable of being
regulated and adjusted in size, as and for the purpose described.

page_text: 3rd. The application of these improvements in connection with rocking
or moveable fire-bars, or any mere modification of the same.
In witness whereof, I, the said William Thornley, for and on
behalf of myself and the said Samuel Spencer and Joseph Wright,
have hereunto set my hand and affixed my seal, this Twelfth
day of July, in the year of our Lord One thousand eight hundred
and seventy.
Witness,
JOHN G. WILSON,
Patent Office,
71, Market Street,
Manchester.
WILLIAM THORNLEY. (L.S.)