IMPROVEMENTS IN GAS STOVES
Year: 1861

page_text: PROVISIONAL SPECIFICATION left by Charles Chalmers at the Office
of the Commissioners of Patents, with his Petition, on the 11th June
1861.
I, CHARLES CHALMERS, of Edinburgh, in the County of Mid-Lothian, North
Britain, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN GAS STOVES," to be as follows, that is to say :-
This Invention relates to the arrangement and construction of gas stoves,
which the Inventor designates the "Merchiston gas stove," suitable for heating
purposes, and is based to a certain extent upon an Invention of a somewhat.
similar nature for which Letters Patent were granted to me, datod the
15th day of November, 1859, numbered 2588. Under one modification
the improved gas stove is arranged as follows:-Two, three, or other suitable
number of Bunsen burners are arranged upon a base plate, each of these
burners is connected by a separate pipe and stop cock with the pipe from
which the supply of gas is obtained so that one or more burners may
be used as required, the Bunsen burners are surrounded by a small air
chamber which is furnished with a door in front to admit of lighting and
regulating the burners. An air pipe is conveyed from the exterior of the
building and concealed, if required, either beneath the floor of the room or
behind the skirting board. This pipe is by preference about three inches in
diameter; it opens into the air chamber where the air mixes with the gas as
it flows up the tube of the burner and greatly adds to the heating power.

page_text: The stove consists of a metal cylinder of about three feet and a half in height
by fifteen inches in diameter, the cylinder may be formed of iron, brass, plated
metal, or of silver. The cylinder is supported on tripod feet which extend to
the upper part of the air chamber so as to admit of ready access thereto. The
top of the cylinder is by preference of a dome shaped figure and is completely
closed, the lower part of the cylinder is formed of a conical figure. In the centre
of the stove is fitted a vertical tube which extends to within a short distance of
the top of the cylinder and passes out through the bottom, and into the air
chamber, where it terminates just above the burners. A door in front of the cylin-
der affords access to the interior for the purpose of cleaning it when necessary.
The admixture of gas and air burns with a blue flame, giving off an intense heat,
the volume of heated air passes up the central tube and then into the stove, the
surface of which radiates the heat into the apartment or building. The most
important feature in the arrangement of this stove is the mode of getting rid
of the vitiated air and products of combustion. These impurities are carried off
at the lower part of the stove by means of a pipe which is carried out from the
bottom or near to the bottom of the stove. This pipe extends either outsido
the building or is carried into a contiguous chimney. As the external air flows
in through the inlet pipe and passes around and through the gas flame it
becomes very highly heated, and the heated air as it impinges against the top of
the stove parts with a portion of its heat and so becomes specifically heavier
in proportion. The current of heated air as it ascends continuously occupies
the place of the cooler portion of the air, and thus the vitiated air is caused to
descend and pass off by the outlet pipe. In its downward passage the air
gives off its heat to the surrounding metal of the stove so that it passes
away by the outlet pipe, carrying with it little or no heat. In this manner the
whole of the heat is economised and rendered available whilst the building or
apartment is kept entirely free from the impurities arising from the combus-
tion of the gas. The vitiated air passes off into the outlet tube so that the air
of the room or building is uncontaminated by the presence of the stove, and at
times is maintained at an agreeable temperature, a ventilator only being
necessary at the upper part of the room to carry off the heated air. This
store may also be arranged to adapt it for culinary and other generally similar
purposes.