IMPROVEMENTS IN GAS HEATING AND COOKING APPARATUS
Year: 1852

page_text: LETTERS PATENT to William Fraser Rac, of Edinburgh, in the
County of Mid-Lothian, Brass Founder, for the Invention of
"IMPROVEMENTS IN GAS HEATING AND COOKING APPARATUS."
Scaled the 30th April 1853, and dated the 15th November 1852.
PROVISIONAL SPECIFICATION left by the said William Fraser
Rae at the Office of the Commissioners of l'atents, with his
Petition, on the 15th November 1852.
I, WILLIAM FRASER RAE, of Edinburgh, in the County of Mid..
Lothian, Brass Founder, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN GAS HEATING AND COOKING APPARATUS"
to be as follows:
This Invention relates to various arrangements of apparatus for
the production and application of heat for warming and cooking.
According to one simple arrangement the stove or heating
apparatus consists of a pair of vertical cylinders placed concentri-
cally one within another, leaving an annular space between the two,

page_text: the two cylinders being attached to a base perforated to admit air.
The top of the cylinders is covered over with a diaphragm of wire
gauze or other porous or perforated material, over which diaphragın
is either a single or double dome shaped top, carrying a vessel for
holding water, the dome being for the purpose of causing the heated
air to issue laterally from the stove. The gas burners may be
placed either within the inner cylinder or between the two, the
being either a perforated tube, or an arrangement of fan, union jet,
fish-tail, batswing burners, or burners of a similar class. When the
burners are placed in the inner cylinder, the air to be warmed may
be taken either from the apartment containing the stove, or a
communication inay be opened up between the exterior cylinder and
the outer atmosphere. If the burners are in the annular space
between the two cylinders, the inner one may communicate with
the open air, whilst the vitiated current is carried off by a passage
from the external cylinder. Beneath the gas burners a reflector is
placed. In applying the Invention to heating water for baths or
reservoirs, three cylinders are used, one within the other, the inner-
most cylinder having a series of short, horizontal, open ended pipes
passed through it. The water in the bath circulates through two
pipes, one connected to the top and the other to the bottom of the
apparatus. The gas is consumed in a chamber beneath the
cylinders, and the heated air passes off up through the inner
cylinder, and between the outer and middle one.
For cooking
stoves the chambers are also constructed with an external air space;
that is, one rectangular chamber is placed inside another slightly
larger, the inner chamber being divided by shelves.
The gas
burners are placed beneath the inner chamber, a curved or other
overhanging cover being above them, whilst a space is left between
the top of this cover and the bottom of the inner chamber, to allow
the heated air to pass through, and afterwards up between the
two chambers, and off by a suitable discharge pipe in the external
chamber. A reflector is placed behind the burners, such reflector,
as well as the lining of the inner chamber, being, by preference,
of enamel. Above the chambers is a double top, divided into

page_text: compartments, in which gas is burnt for boiling and other cooking
operations, and on the top a boiling and steaming apparatus may be
laced beated by a ning or nines from the stove beneth
SPECIFICATION in pursuance of the conditions of the Letters
Patent, filed by the said William Fraser Rae in the Great Seal
Patent Office on the 14th May 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
WILLIAM FRASER RAE, of Edinburgh, in the County of Mid
Lothian, Brass Founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by
Her Letters Patent, bearing date the Fifteenth day of November, in
the year of our Lord One thousand eight hundred and fifty two, in
the sixteenth year of Iler reign, did for Herself, Her heirs and
successors, give and grant unto me, the said William Fraser Rae,
Her special licence that 1, the said Willian Fraser Rac, my ex-
ecutors, administrators and assigns, or such others as I, the said
William Fraser Rac, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time
and at all times thereafter during the terin therein expressed, should
and lawfully might make, use, exercise, and vend, within the
United Kingdoin of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN GAS HEATING
AND COOKING APPARATUS," upon the condition (amongst others) that
I, the said William Fraser Rac, by an instrument in writing
under my hand and seal, 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that 1, the said William Fraser Rae, do
hereby declare the nature of my said Invention, and in what
manner the same is to be performed, to be particularly described
and ascertained in and by the following statement, reference being

page_text: had to the accompanying Drawings, and to the Letters and Figures
marked thereon (that is to say);
My said Invention relates to various arrangements of apparatus
for the production and application of heat for warming and cooking
in a more economical and effectual manner than hitherto, according
to one simple arrangement. The stove or heating apparatus consists
of a pair of vertical cylinders placed concentrically one within
the other, leaving an annular space between the two, the two
cylinders being attached to a base perforated to admit air. The
top of the cylinders is covered over with a diaphragm of wire gauze
or other porous or perforated material, over which diaphragm is
either a single or double dome shaped top, carrying a vessel for
holding water, the dome being for the purpose of causing the
heated air to issue laterally from the stove. The gas burners may
be placed either within the inner cylinder, or between the two, the
burner being either a perforated tube, or an arrangement of fan,
union jet, fish tail, batswing burners, or burners of a similar class.
When the burners are placed in the inner cylinder, the air to be
warmed may be taken either from the apartment containing the
stove, or a cmomunication may be opened up between the exterior
cylinder and the outer atmosphere. If the burners are in the
annular space between the two cylinders, the inner one may
communicate with the open air, whilst the vitiated current is
carried off by a passage from the external cylinder. Beneath the
gas burners a reflector is placed. In applying the Invention to
heating water for baths or reservoirs, three cylinders are used, one
within the other, the innermost cylinder having a series of short
horizontal open ended pipes passed through it. The water in the
bath circulates through two pipes, one connected to the top and
the other to the bottom of the apparatus. The gas is consumed in
a chamber beneath the cylinders, and the heated air passes off up
through the inner cylinder, and between the outer and the middle
one. For cooking stoves the chambers are also constructed with
an external air space; that is, one rectangular chamber is placed
inside another slightly larger, the inner chamber being divided by

page_text: shelves. The gas burners are placed beneath the inner chamber, a
curved or overhanging cover being above them, whilst a space is
left between the top of this cover and the bottom of the inner
chamber to allow the heated air to pass through, and afterwards
up between the two chambers, and off by a suitable discharge pipe
in the external chamber. A reflector is placed behind the burners,
such reflector, as well as the lining of the inner chamber, being,
by preference, of enamel. Above the chambers is a double top,
divided into compartments, in which gas is burnt for boiling and
other cooking operations, and on the top a boiling and steaming
apparatus may be placed, heated by a pipe or pipes from the stove
beneath. Figure 1, on my sheet of Drawings is an external eleva-
tion of one of my domestic or warning stoves complete, and
Figure 2, is a corresponding sectional elevation of the stove. It
consists of an open rectangular base A, set upon ornamental feet
riveted to it, and on this base is bolted down the moulding piece B,
carrying the external cylinder or main shell C, of the stove. To
the base is also attached the cross-piece D, from which spring
brackets E, to hold the internal cylinder F, and on this cross bar
is also attached the concave reflector G. The top of the internal
cylinder terminates in an open cone II, and beneath this conc it
has a series of holes in it to form a communication between the
interior of the inner cylinder, and the annular space J, between the
two cylinders. The outer cylinder is also open topped, but it is
covered in by a permeable diaphragm K, and this again is covered
by an ornamental cover piece 1, secured by catches M, so as to be
removeable, and having an expanded open lower side. Over this
cover is a hollow air chamber N, bolted down to the cover L, and
supporting the open vase O, as the finish at the top. Access to
the burners is obtained by the bottom side door P, fitted with a
tale window Q, in the centre, a corresponding hole being cut in the
inner cylinder to suit. The gas enters to the burners by the pipe
R, turning up by an elbow in the centre of the inner cylinder to
carry the three branches for the three burners S. This compound
gas burner, when lighted up, heats the air in the inner cylinder,

page_text: and from this the outer cylinder becomes heated, whilst air passes
up from below both through the inner cylinder and the annular
space J. The air thus heated passes off laterally from the top by
the expanded cover L, whence it is diffused over the apartment.
Figure 3, is a front elevation of my improved gas cooking
apparatus with the door open, and Figure 4, is a transverse vertical
section of the same at right angles to Figure 3. It consists of an
external rectangular case A, having an open bottom, and being
supported on four bracket legs. Within this outer shell is an
inner case B, attached by studs and connections in such way
as to leave a clear open air space C, between the two casings
open at the top and bottom. This inner case is fitted up with
bracket pieces, as slides to carry moveable cooking shells D, E,
and a perforated grating shelf F, beneath. The gas enters
by the pipe G, and regulating stop cock H, with an external
lever handle. From this stop cock the gas passes along the
pipes I, round part of the base of the external chamber, turning
upwards and completing its circuitous route by the upper pipe J;
thence it bends downwards through the curved pipe K, finally
entering the lower burner pipe L, carrying the set of burners M;
so that in this way the gas is well heated prior to being burnt
by radiation from the burners upon the conducting thoroughfare
above: this range of burners is close to the interior surface of the
case, and the entire range is covered over and protected from the
dripping of matter from above by the curved overhanging screen N,
a similar cover being also upon the inside of the door O. When
the gas burners are in action, the heated current derived from the
external air supply entering at the bottom passes up through the
space C, between the two casings, and escapes through the aper-
tures I, in the outer casing, and finally makes its exit along
a pipe in communication with the larger opening Q, in the pro-
jecting chamber R, behind the stove. At the same time direct
radiant heat passes up to act upon the articles placed upon the
cooking shelves above; and any dripping or discharge from these
articles is caught by the base receiver S, entered beneath the

page_text: burners. A short distance above the termination of the air
casing C, is a close cover T, from which a sliding hook U, capable
of back and forward traverse, is hung for the suspension of articles
requiring to be cooked in this way. Above this is an air chamber V,
containing gas burners and pipes for cooking by boiling, stewing,
and other processes, on the top W. For this purpose the gas
is led up from below by the branch pipe X, to the horizontal
length of pipe Y, passed along the bottom of the chamber V, and
from this pipe stop-cock branches Z, stand up to conduct the gas
through the curved branches a, to the burners b. Each of these
branches is swivel jointed at c, so as to be capable of very nice
adjustment on the floor of the chamber V. This arrangement of
burners is covered over by the top plate W, from which short
open casings or flue pieces d, project inwards over each burner.
The gascous supply is regulated by a set of levers projecting from
the stop cocks outside the front of the stove. The sides of this
upper chamber are perforated as at e, to admit air from without,
and thus an effective source of heat is got up for acting upon the
pans or cooking utensils on the top. The peculiar form of the
burner tubes in this case also, affords the means of licating the
gas prior to combustion, as each tube bends downwards over its
burner, and the heat from the burner necessarily radiates directly
up against the tube. The door of the stove is also fitted in this
instance with a tale window f. Figure 5, is an external elevation
of a modification of my gas heating apparatus as applied for heating
a bath or water reservoir. Figure 6, is a corresponding longi-
tudinal section of the same. It consists of a base disc water
space A, from which three pipes 13, stand up to afford supports
for the duplex conical water chamber C, above, as well as to forin
water ways to connect the base water space A, with the conical
annular water space D. This space D, is formed by the coin-
bination of the external conc E, with the internal one C, across
which last flat water tubes F, are passed at a slight inclination.
These pipes are open at both ends into the water space D. The
inner conc C, is open at top and bottom to admit air freely through

page_text: if, and the combined shelves are covered over by the open bottomed
case G, resting by its lower edge upon supports H, outside the
cone E. The gas is brought in by the pipe I, opening into an
annular pipe J, laid upon the surface of the case A, and studded with
gas
s burners K. The heat from these lights then acts upon the interior
of the cone C, and upon the transverse tubes F, and the heated air
current passes up from below and strikes against the upper disc
water space L, set a short distance above the open top of the conical
chamber, and opening into the water space D, by the three branches
M. In this way the heat acts on a very extensive area of water space,
and as it is stopped by the rounded top N, of the outer cover G, it
descends and circulates outside the cone E, passing off beneath
the open lower end thereof. The water heated in this way passes off
from the lightest strata at the top through the pipes M, and the
disc chamber L, and emerges by the branch P, into the bath or
reservoir Q, to be heated; at the same time the heavier cold water
in the bath descends by the bottom branch R, and pipe S, and
re-enters the conical water space D. In this way a constant heated
current is kept up so long as the gas is burning. A stop cock
is also fitted at T, in the top of the disc chamber L, by which
the air may be separately drawn off. A door U, with a tale window,
is fitted to the outside of the cone E, and access to the gas
chamber is thus obtained by forming a corresponding hole in the
water space. Figure 7, is a separate sectional detail, shewing
a simple mode of heating the gas prior to being consumed. The
gas enters at A, and making a detour round the burners along the
tube B, it re-enters a separate division C, of the burner tube,
finally escaping by the burner D. Figure 8, is an elevation of a
separate boiling and steaming apparatus, to be placed on the top
of the cooking stove. This consists of a pan or water vessel,
having a slightly concave bottom B, to collect the heat from the
burners and heated air of the stove. Through this concavity,
two pipes C, are made to open as heated air passages, to conduct
the heat from below, and up through the fluid in the pan. In
this way the contents of the pan are rapidly heated, and a per-

page_text: forated diaphragın D, serves to receive articles to be steamed,
the whole being covered by a concave top or cover E, per-
forated to receive separate smaller cooking vessels F.
Having now described and particularly ascertained the nature
of ny said Invention, and the manner in which the saine is or
may be used or carried into effect, I may observe, in conclusion,
that I do not confine or restrict myself to the precise details or
arrangements which I have had occasion to describe or refer to, as
many variations may be made therefrom without deviating from
the principles or main features of my Invention; but what I con-
sider to be novel and original, and therefore claim as the Invention
secured to me by the herein before in part recited Letters Patent, is,―
First, the general arrangement and construction of apparatus, or
means for heating and cooking as herein-before described.
Second, the system or mode of constructing gas heating appa-
ratus with duplex chambers, to produce heated air spaces, in
combination with an expanded concave cover or top to diffuse and
conduct the heat.
Third, the application and use of reflectors for heating and
cooking apparatus.
Fourth, the adaptation of a concave reflector beneath heating
and cooking burners, as represented in Figure 4, on my sheet of
Drawings.
Fifth, the application and use of overhanging covers for pro-
tecting the gas burners.
Sixth, the system or mode of arranging, heating, and cooking
apparatus, wherein the burners themselves are made to heat the gas
prior to combustion thereof.
Seventh, the application and use in heating and cooking ap
paratus of burners of the batswing or fish-tail class, or other
burners of diffused flame consuming their own smoke.
Eighth, the application and use in heating and cooking appa-
ratus of enamelled reflecting surfaces on the inner side of duplex
air chainbers or spaces.
Ninth, the system or mode of heating water, and producing

page_text: a heated fluid current by means of an annular water space, with
tubular connections, as hercin-before described.
Tenth, the system or mode of deflecting and diffusing the
heated air by means of a deflecting cover, as herein-before
described.
Eleventh, the system or mode of heating boiling or steaming
apparatus by means of air passages passing through such apparatus
and communicating with burners beneath.
In witness whereof, I, the said William Fraser Rae, have
hereunto set my hand and seal, this Twelfth day of May,
in the year of our Lord One thousand eight hundred
and fifty three.
WILLIAM FRASER RAE. (L.s.)