CONSUMING OR PREVENTING SMOKE IN CHIMNIES AND FURNACES
Year: 1856

page_text: PROVISIONAL SPECIFICATION left by William Smith and Donald
Bethune at the Office of the Commissioners of Patents, with their
Petition, on the 26th December 1856.
We, WILLIAM SMITH, of Number Eighty-five, Margaret Street, Cavendish
Square, London, Engineer, and DONALD BETHUNE, of Cambridge Terrace,
Hyde Park, London, Esquire, do hereby declare the nature of the said Inven
tion for "CONSUMING OR PREVENTING SMOKE IN CHIMNIES AND FURNACES," to be
as follows:-
Our said Invention consists in improvements in the construction of stoves or
grates and the flues leading therefrom to the flue of the chimney, and in the
construction of doors of furnaces, by which improvements the smoke that
ordinarily arises from fires in stoves, grates, and furnaces is consumed or pre-
vented. And we consume the smoke or prevent it from rising by the
admission of air in certain parts of the flues and doors, or near thereto. By
one of the plans we adopt, we close the opening from the grate or stove into
the flue of the chimney, as now generally in use, and we make the draught (by
means of proper openings for that purpose) to pass back of the grate into the
flue of the chimney, and air is admitted through a plate placed opposite to and
at a little distance from that part of the grate through which the draught
passes into the flue of the chimney, so that such air comes in contact with the
gases arising from the fuel in the grate, and causes such gases to ignite, and
are thus consumed. By another plan, the draught is made to pass under the

page_text: grate and into the flue of the chimney, and air is admitted through a plate
placed at or near the bottom of the flue which passes into the chimney, so that
such air comes in contact with the gases arising from the fuel in the grate, and
ignition takes place. The air may be admitted higher up the flue if necessary.
By another mode, we alter the size of the opening above the grate or stove
now in common use, and alter its shape; and wo also in some instances alter
the shape and angle of such opening, and we place what may be termed a hood
at or near the opening of the grate or stove into the flue of the chimney, which
hood we perforate with holes or openings, so as to admit the passage of air into
the opening, and which air comes in contact with the gases arising from the
fire in the grate, and causes such gases to ignite. We also use a damper in
this as well as in the other places mentioned, and blowers may be used when
the fires are first lighted. And we do not confine ourselves to the details
herein inentioned.
For the consumption of smoke in furnaces we employ. what may be termed
à double door with a space of about an inch, more or less, between the two
doors, and we make an opening or openings for the admission of air near the
top and bottom of the outside door, nearly the whole length of the door, and
about an inch wide, more or less, according to the size of the door, and we
place bars or ribs between the doors about half an inch in depth, so as to
Úreak the current of air and to cause the air to pass over them, and thus
become heated, and then enter the furnace about the centre of the inner door
through openings made for that purpose nearly the whole length of the inner
door, and of a width corresponding with the size of the openings in the outer
door, allowing for the expansion of air on its becoming heated in its passage
between the doors to the furnace. Valves may be fitted to the openings of the
outer door for regulating the supply of air; and we do not confine ourselves to
the details herein mentioned.