IMPROVEMENTS IN THE CONSTRUCTION OF APPARATUS FOR COOKING BY THE AGENCY OF GAS, PETROLEUM AND OTHER SIMILAR PRODUCTS
Year: 1884

page_text: I, JOHN BALBIRNIE of Nelson Place, Sheffield in the County of York Doctor
of Medicine do hereby declare the nature of my said invention for IMPROVEMENTS
IN THE CONSTRUCTION OF APPARATUS FOR COOKING BY THE AGENCY OF GAS,
PETROLEUM AND OTHER SIMILAR PRODUCTS to be as follows:-
My invention relates to improvements in the construction of Apparatus for
cooking by the agency of gas, petroleum and other similar products, and which
I call the "Sanitary Cooking Stoves"; the object being to produce an apparatus
that shall while securing the full heat of the ovens, be able to exclude, when
required, the deleterious products of combustion from the interior of the ovens, and
also from entering the apartment in which the stove is fixed; two impossibilities
in gas stoves as at present constructed.
My Invention consists (broadly speaking) in constructing the two sides and
back of the ovens, or of the complete stove, with a double wall having a hot air
space which may be either in large compartments or may be subdivided or
channelled into winding flues or hotair passages for the purpose of conducting the
heated air over all the surfaces and finally to the chimney, also in the novel con-
struction of the boiler, likewise in the peculiar arrangement of the gas pipes or
burners; and notably in the interchangeable sets of pierced top-plates for boiling
and other purposes, according as vessels of larger or smaller sizes are required.
The entrances and the exits of all the hot-air receptacles or flues are protected'
by slides which cut. off or graduate the quantities of hot air they admit.
My Invention may be described as consisting essentially in the construction of
Cooking Stoves (heated by gas or other suitable agent) with an upper and a lower
oven and a boiler placed between them, supplied at will from the waste heat of
either, of all which it must be understood that there may be various modifications
in shape aud arrangement.
I place the gas pipe or burner in a space under the floor of the lower oven, and
admit the air to support combustion through a winding Que and in contact with
the heated metal so that it shall attain a high degree of temperature before
reaching the gas jets; and thus a very considerable saving of heat is effected.
The air heated by the gas, and the products of combustion pass into the hot air
cavity between the walls, or into the winding flues formed therein which convey
the intensely hot gases over the three sides of the oven to the underside of the
boiler A sort of trap door is provided in the floor of the oven over the gas jets;
so that if in any case it may be desirable to let the full force of the gas flood the
interior of the oven it can be done.
Both upper and lower ovens have direct exits into the chimney, which ensures a
perfect ventilation.
The Boiler, (which comparatively is of a large capacity) is placed between the
ovens, both for convenience and for economy of heat; it occupies the full area of

page_text: space and projects in front sufficiently to form on its top surface a shelf or support
for dishes drawn from the top oven.
This projecting portion is made of an angular shape, sloping back from the top
front edge. In the top the opening for cleaning out and filling is placed; and in
the sloping underside I place the draw off tap.
This projecting.portion being cut away on the undersido does not interfere with
the light, or prevent easy access to the bottom oven.
I admit the heated air to all the sides of the boiler except the front; and by
means of radial ribs the heated air is prevented escaping in a direct course to the
exit, but is directed over the surfaces; so that it may be utilised to the greatest
extent possible before it escapes to the ovens or their flues.-An auxiliary burner
is placed in a space under the boiler, constituting a double bottom, for heating the
boiler with its own gas supply as occasion requires.
The upper oven is surrounded by a continuation of the winding hot air
passages as before described, which finally lead to the chimney. The top plate of
this oven may be used as a support for culinary vessels under actual cooking, and
also simply to keep their contents hot till served.
It is pierced with a number of holes of various shapes and sizes, in which are
placed cast iron removeable sockets, varying in depth as required, in which the
bottoms of correspondingly shaped pots or kettles are placed, and which thus
depend into the body of the oven; more or less according to the size of the vessel,
or the nature of the operation.
The gas arrangements are of a novel character. I arrange two or more series of
supply pipes provided with sockets or nozzils, upon which may be placed straight
or shaped perforated burners, removeable and interchangeable.
These burners are suited to the various sizes and shapes of the pots or kettles,
and can be adjusted to go under the deepest vessel, or to heat the hot plate by
direct contact.
Oweing to the construction of the socket joints, the burners can be fixed in
position, or removed with the greatest ease; and upon the pipes forming the
burners I put a number of ferules that will slide along the pipe, and may be
passed over and close the orifices when it is desired to reduce the number of
lights.
When the top of the oven is required as a hot plate only, the openings are closed
with flat lids, and both lids and sockets are made to fit so that no gas fumes may
escape at the circle of contact.
A cover may be used to enclose dishes placed on the hot plate, by which means
a cooked dinner may be kept hot for hours without further cooking.
The residual air chambers occupying the outsides of the upper oven are made to
receive and retain a large body of the overflow or surplus hot air of the oven
before it escapes to the receptacles or flues; this hot air is with great difficulty
dislodged, and answers the purpose of a supplementary hot air supply.
Lastly, the outersides and back of this cooking apparatus, are channelled into
flues or passages, being a repetition of those before described to receive and
thoroughly exhaust the hot air, and pass it forward to the exit chimney; I do not
however bind myself to employ these outer channels or flues in all cases.
The like provisions may or may not be made in the doors of the ovens, preferably
by making them with one receptacle or chamber, having inside holes or slits at
the top for the entrance of the overflow hot air, with which they are filled, being
as effectual (as far as they go) as the sides of the ovens which are the main
heating medium.

page_text: Improvements in the Construction of Apparatus for Cooking by
the Agency of Gas, Petroleum, and other similar Products.
By JOHN BALBIRNIE A.M. MD. Consulting Physician, Member of the Council of
the University of Glasgow, No 2, Nelson Place, Sheffield-I JOHN BALBIRNIE do
bereby declare the nature of my invention for the above purposes (called the
SANITARY GAS COOKING STOVE) and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:-
Before describing his Invention in its details, it will set in a clearer light what
the Inventor has succeeded in accomplishing, if he first states the improvements
called for by past painful public experience in the working of gas cooking stoves.
1st The means of carrying off completely, & directly into the chimney, tho
products of combustion now allowed free escape into the apartment where cooking
goes on.
2nd To put a summary stop to the invited, reckless, needless injury to health
inflicted by breathing an atmosphere polluted & poisoned by gas-einanations.
3d To save the waste of heat which is the least evil of this "matter in the wrong
place"-this overflow & outlet of noxious fumes into confined-spaces-kitchens-
family residences-cooking class-rooms, &c. from all which the public health
demanded their imperative exclusion.
A practical illustration-an instance in point of this mischief will be allow
a physician. To avoid the smuts, & the inevitable tainting of food by the flooding
& Faturation of the cooking cavity with gas, (as stoves have hitherto been
contrived) it has been found necessary-besides introducing an immense amount of
air in the "Bunsen Burner" to drench the oven (so to speak) with great currents
of cold air, quite over & above the supply of oxygen required to support com-
bustion But all this waste of heat, & unscientific "ventilation of ovens" (so called)
avails nothing to purify the atmosphere hitherto prevailing around the current
"cookers" & "kitcheners." As note the following "modern instance." The Corn
Exchange Hall of Sheffield-a spacious & lofty inclosure-grew almost unbearable
from this cause, long before the hour expired that was devoted to cooking lessons
there, with the best gas stoves of the day! This occurred at the "Exhibition" of
these articles in March 1883. If, then, this be the peril & penalty of ga-cooking,
under the most favourable circumstances for its trial, what must be the condition of the
atmosphere of a small confined kitchen under the like operations? In the public
example in question the cooking done was on the smallest family-scale! Does such
a state of matters not call for a remedy? Could any Sanitarian look upon this with
the least degree of allowance?
4th A guarantee is required that in an apparatus of the first necessity to all
civilised society, perfect efficiency, & cheapness, & suitable speed, in preparing food,
should in no degree be compromised.
5th and lastly as Gas Works & Gas companies are the luxuries of popular
places; & gas therefore out of the question in moving life, on shipboard, in Pulman
cars, on the tented field, & even in the settled abodes of isolated country houses,
farms &c, it should be an essential principle in the construction of a valid cooking

page_text: stove, that it work equally well-if not quite so cheaply-with parafine, or other
oil, or spirit, or fuel fit.
Now for the mode in which this Sanitary Cooking stove (so called distinctively)
makes good its claim to accomplish these & all its other specific ends. It consists
essentially in or of three distinct & separate ovens; close, or closable; & two of
these are subdivisible by partitions into minor ovens, which can be used indepen-
dently; making a series of eight ovens altogether; all to be brought to bear at one
time where much cooking is to be done; & from only two or three sources of heat.
Oven number one occupies two thirds of the top of the stove. In size A it is
22 inches square, 10 inches deep, & is divisible into two or four compartments-
all intercommunicating. Bencath this-in certain specimens only of the stove-is
a floor two inches deep, with winding passages, for the admission, & heating,
& distribution of the air needed for combustion. This is received into the cooking
compartments above, thro' slides working in the floor, at will. Two of the partitions
of these compartments are on hinges. The oven, or quadruple series of ovens, now
described, has (in size A) four piercings in its "top plate" for the admission of
capacious cooking vessels which descend from 3 to 5 inches, some more, some less,
into the blazing furnace below. All this boiling, or stewing capacity is instan-
taneously convertible into roasting, or grilling, or baking, or frying cavities; simply
by putting on the lids, & lighting a different set of gas pipes! There is a narrow
but free passage in succession from the various compartments which permits each to
receive the the heating power of its neighbour almost unexhausted, & to transmit it
on to the next: this in addition to its own independent supply of heat. More or
less of the air to support combustion we introduce thro a Bunsen pipe.
Oven number two is the largest division of the Sanitary Cooking Stove; occupies
nearly its lower half; & reaches to the ground. It is a solid massive cast iron box
into which fumes cannot possibly get entrance. It is devoted chiefly to roasting
& baking; altho' available for boiling or stewing.
Oven number three (called, for distinction's sake,) The Hot Closet (& serving all
the purposes of such) is perhaps the most useful, convenient & economical arrange-
ment of this improved stove. It has two small serviceable independent ovens ; one
on each flank of its enclosure; & in the intermediate space, the lid of the capacious
Boiler, on the front third of which this Hot Closet is built.
The Boiler here fal's to be described. It occupies the central position of the
entire stove; easy of access to draw from, to fill, or to clean; & is relatively of great
capacity; here, in size A (the smallest made) of about nine gallons. It is situated
immediately under the top oven (No 1) and projects ten inches beyond the line
of the stove-front. It is cut away in angular fashion; sloping downwards towards
the roof of the bottom oven. Here is fittingly placed the draw off tap. This
projecting roof of the Boiler constitutes a firm foundation on which are built the
Hot closet, & its small ovens.
Here it falls into place to describe the means-qu'te new in gas or oil cooking—
for heating the ovens and the boiler. The large lower oven & the boiler have a
double bottom two inches deep. In this is fixed the furnace in which is placed the
gas-pipe, or received a long narrow vessel holding the oil or parafine &c. From
this cavity (controlled by a slide) are led off the blazing products of combustion
first detained (for economy of heat) in winding floor passages; thence rising thro'
a series of flues lining the sides & back of the oven & the boiler, till they reach
their top surface. On this, the burning fumes are spread an inch deep, & retained
as so much residual, residential, or overflow heating material. There are in all,
three layers of these winding sido & back flues. The end of the first layer being
reached, there is an opening into the flues of the second layer. Down these the
burning stream winds, till it reaches the point it started from in the first layer of
flues that nearest the massive walls of the oven & boiler. Here the exit opens
into the outermost flues of all which are twice the depth of the first & second series.
The former are only one inch deep. The deeper flues are wrought on the interior
qurface of the outside plates of the stove. These wind round its sides & back;

page_text: carrying off all the products of combustion everywhere generated, & lealing them
for final exit directly into the chimney, by a massive upcast flue securely fixed to
the back plate of the apparatus. Near the top of this there is-in only some of the
stoves a small slide, with a set of thin bars fixed across the flue. This is to
receive a small half ounce cup of parafine, which lit, & the slide let fall, uses up
the air retained in the winding flues. So, when the furnaces are first lit, a draught
is established in the long passages that will at once start the necessary currents.
It is essential here to note another new & exclusive feature of the Sanitary
Cooking Stove, viz. the substitution of slides for doors in the larger ovens. The
latter (doors) act necessarily as air-pumps every time they are pulled open-and a
cook never but pulls them, & that with a slam. The slides will not suck out the
the hot air in this fashion. But this is only half of this improvement. We use
thick plate glass alone, or in the shape of a panel for one or both of the pair of slides.
This is nearly as strong, & quite as effective, as would be its iron fellows, in retain-
ing the heat; & on all occasions, (where much steam is not generated) enables the
cook to reconnoitre the condition & progress of her preparations without roasting
her face, or cooling the oven. Springs prevent the breakage of glass.
An entirely new expedient to guard against the escape of fumes, it behoves here
to note. This accident is only possible in the top oven by carelessly & suddenly
lifting off the massive iron lids that close the openings thro' which the culinary
vessels are let down into the furnace. These carefully slid away, there is no escape
of fumes. The cold air rushing in represses all such escape, & netivates the
circulation from one cavity to another, till the whole products of combustion
generated in the top oven escape into the wall flue circulation for final exit.
In cases where it is expedient to prevent any risk of escape of fumes here, I
adopt a set of iron-moulds of the lower half of the cooking vessels-or up to the
flange by which they hang to the top plate. These moulds also are kept hanging
by their flanges; & get so bot that a pot or kettle plunged into them is hastened.
very much in reaching the boiling point. By this, no fuines can possibly escape;
& an actual concentration of the heat of the oven is gained for the vessels placed in
such socketa.
I should here state that my stove (size A) stands 40 inches high, & is 22 inches
square. The Boiler, however, projects ten inches beyond the front; & as the Hot
Closet is built on this projection, the top plate (which covers all in) is 22 inches
from side to side, & 32 inches from front to back. This entire surface gets so hot,
from the gas playing directly upon it, here & there below, that, when the lids are
put on, this entire superficies may be covered over with boiling, or stewing, or
baking dishes.
The whole apparatus will allow half a dozen cooks to work round it—with
elbow-room for each; & yet, it is so cleanly, that it may be set up in the Dining
Room of a Club Hou-e, without being an eye-sore, or nuisance; but it will not b
too large or unhandy for the moderate kitchen of a young couple commencing life.
Explanation of the accompanying drawings illustrative of the Gas Sanitary
cooking stove, & of the series of entirely new & original constructive arrangements
it involves differences as marked & as advanced (compared with the existing.
apparatus for the purpose) as exists between the Henry-Martini Rifle & the old
"brown bess"; or between a Pulman Car, & a third class carriage, as found on.
"photo"
"loop" lines thirty years ago. A single glance at these drawings & the "
of a typical gas "cooker" of the very best class, will satisfy any unprejudiced mind
inquiring what, & how many, are the features of novelty and improvement in my
Invention. Furthermore, for the minute details of these specialities I claim to be
protected I refer to their summing up under distinct heads-I. II. III. IV. V. VI.
VII. VIII. IX. X.
Fig. 1. is a lateral section from front to back of the stove. (see dotted line A-B
in Fig. 2) The foundation of the whole is the large bottom oven C, 18 inches
deep, 15 inches high, & 14 inches broad. D-D represent movable oven plates.
E the furnace under the oven, with the line of section here transferred to X-Y.

page_text: Here refer to Fig. 7. A for the ground-plan of this furnace; & the immediate
flues leading off from it. The three Fs indicate the succession of primary flues
winding round the oven walls. The three Hs are the second series of winding
Blues into which the former open, & bring down the hot currents to the point they
started from. Thence they find exit into the outermost or departing flues: (sce the
six Is which are double the capacity of the flues F & H) For the windings of
these flues see Figs 8 & 9. J is the final exit-flue running up the back of the stove,
& bending at K into a new joint of tube carrying the products of combustion
directly into the kitchen chimney. The point of issue from the testing flues I into
this back departure-fluo is indicated by the *. This large foundation-oven C,
detached from the rest of the apparatus, may be made of all sizes; & constitutes of
itself an integral & perfectly acting contrivance for its purpose; & under fair
treatment not easily derangeable. Hence, the covering shield of the Patent Office
is respectfully solicited for it, as an essential means for the working man of of
'making his bread" in a double sense. The great saving of heat (economy of fuel)
is its least recommendation. In most other furnaces the heat disengaged makes its
quickest outlet to the skies; only an infinitesimal portion of it being exhausted.
In coal-fire kitchen ranges things are a little better; for there is an open space left
all around the walls & top of the oven, by which the heat escapes in one great
broad wasteful wave or current into the chimney. But in the present oven the
heat is chained to its work (as it were) & made the slave of the cook. It escapes
in the narrowest streams (compatible with its free passage) & these are kept close
applied to the oven walls, & wind round them from bottom to top in a close con-
tinuous rope of heat. At the end of this its first circuit, this rope of heat (allow
me the phrase) gets into a second series of flues-a repitition of the first,-& comes
back to where it started from. There it enters into a third & wider system of
flues, coursing along the whole outside plates of the stove before it is permitted to
"strike work" & depart. I reserve to myself the power of adding more flues for
the purpose, where the greatest economy of heat is asked for. But the recom-
mendation of this sort of oven to all sanitarians is that there is no poisoning of the
kitchen, or the bake house, with the fumes necessarily escaping in all other gas
ovens. The swinging of their open doors, to take cooked things out of them,
makes a clean sweep, for the nonce, of their entire cubic aerial contents; & these,
of course, strongly impregnated with gas.-But to proceed with out description.
L represents tho Boiler with precisely the same arrangement of furnace & flues,
& their top residual (or overflow) hot air-floor G which we omitted to refer to in
describing the oven below. The Boiler (nine gallons) is placed in the central
compartment of the stove; & this, on the ground of most convenient access to what
will be oftenest in demand, & as most economically heated, the proverbially hot
situation "between two fires"-which will often supersede its own fuel-supplies,
where merely warm water is wanted. The boiler detached will also "work
perfectly M. The top compartment of the stove is ten inches deep & 22 inches
square. It is divided into two ovens, which are further subdivided by a folding
door in each, constituting four conveniently accessible cooking cavities; equally
available for all the purposes & processes of boiling & stewing, roasting & grilling
& baking & frying. The latter operations can be performed inside; while the top
of the stove is utilised for the former. And all this, without the escape of the
noxious gas-fumes into the apartment-a very different state of matters from what
salutes the nose & the lungs from the top of our present "gas-cookers." The "top
plate" is pierced with openings for the admission of culinary vessels-to be inserted
at any depth into the oven; up to seven inches, for the present. A glance at the
section will shew all this. For the top-plate openings see Fig. 3. a a a a. For the
anatomy of the interior of the top compartments, or."apartments" (for such they
really are) with their entrances & outlets, & connecting corridor (for free passage)
see Figs 5 & 6, & then study Fig. 4. QQ represent one bar of a floor of them
here running across the ovens, two inches from the floor-thus guarding the gas
pipes laid on this floor or the parafine dishes or "vessels" their substitute. R points
"

page_text: out the passage that separates the two. lateral overs; & is, at the same time, the
conduit of the hot air current. S. S is a coil of gas pipe flattened, or a parafine
vessel concentric with the piercing in the top plate. Consult here Fig. 5. for the
full ground-plan of the gas-distribution on the floor of the top ovens; & Fig. 6. for
the gas-pipes laid along the ceiling" of the same. Tindicates the innermost of
the two right hand cooking cavities; with one of the larger pots let down, full
depth, into it. U is the posterior of the two left hand ovens, with a kettle let
down into the opening; with anfficient space left (as is seen) for V a "joint," & its
dripping pan, and exit. W refers us to a distinct Fourth Compartment of the
Sanitary Gas cooking stove-the Hot Closet. This is built on the top of the front
third of the boiler, and is 22 inches long, ten inches wide, & about ten inches in
height, for the present. These measurements as all the other measurements—will
vary with other sizes of the stove. X. X. X are the residual hot air chambers; or
double walls & floors that constitute the sides, top, & bottom of the hot closet.
Z the lid of the boiler; most conveniently reached on the floor of the Hot Closet.
Y represents a large stew pot "at work proving the double function of the hot
closet; that, not only will it be a great receptacle for warming service-plates,
& "dishes" of all sorts; keeping joints hot till wanted; "airing" an invalid's
sheet, blanket, great coat, or cloak, &c. (these things, of course, wrapped up in
towel or newspaper ;) but it will be hot enough for actual cooking. 4 Throttle
Valve
Fig. 2. shews the front "elevation" of the Sanitary Gas cooking stove: revealing
clearly the three essential, distinctive, separate, yet integral compartments into
which it is divisible. The upper cooking cavities; the central Boiler; & the
Lower Large Oven are, to all intents & purposes, each, individually, one apparatus
in their use, ends, & action; and, if detached, & made to various scales of size,
would answer all the requirements of boiling, roasting, toasting grilling, baking &c.
To split this machine up into its component parts, & to make these parts
extensively available for the wants of those whose purposes they would answer
without going to the expense of buying the completed store; the Inventor waits
for the authorisation & protection of the Patent Office.
NB. The dotted lines ou the left hand side of the stove shew, in profile, the
position & course of the gas pipes that are firmly secured to the strong iron
casing. Z. Z. represent the entrance into the furnace of the boiler, & into
that of the lower oven. G G Groove of slides. FF springs acting as " buffers."
PP Massive panels of plate glass. K oven shelf. L New "Bussen" M Mouth
of new 14 Bunsen."
Fig. 3. Represents the entire "top plate "-that covering the ovens proper,
& that covering (b) the "hot closet "-in all 22 inches broad, & 32 inches long:
a. a. a. a are the four openings for the reception of pots & kettles &c. The number
of these is increased, as well as their size, according to the object & capacity of the
required stove: So, also, the depth into which these vessola descend into the
furnace. When much cooking takes place the top plate alone, without removing
the lids, is hot enough for most culinary operations; & may have its entire surface
covered over with vessels. All this while the interior is doing hard duty, roasting
or grilling, or baking or boiling!
Fig. 4. is a section shewing the interior arrangements of the left hand division of
the upper compartment of the Sanitary stove. A is the posterior or smaller of its
two chambers B its front oven. C the division between these two cavities formed
by the door, which, when put up against the wall, makes this whole side one oven.
[The right hand division of this upper compartment of the stove has also its door
for the same purposes]. D represents the position & course of a gas-pipo set
against the left wall for roasting purposes. E is another gas-pipe running up to
the roof of this chamber, & bending across at in front of the piercing in which
the vessel F is set. To see this accurately, refer to Fig. G. M. In the posterior
cavity those cooking pots are seen "at work"; G resting on the bars of the
grating (K) placed across the oven at two inches from its bottom. S. S. shew the

page_text: central gas-pipe circles flattened concentric with the openings in the top plate
above. J represents a small " joint" cooking in its dripping pan: the wholo
shewing the power of the oven to cook on its grating below; while its top is
filled with pots or kettles. L. L repeat the shewing of the moulds of the pot-
bottoms (note the heavy black lines) let into the top plate openings, to guard
(in certain exceptional cases) against the escape of fumes into the apartment.
A indicates the back opening of all into which the hot air air plunges to escape
down into the large winding departure-flues we have already seen lining tho
interior of the outer iron casing of the stove. see K in Fig. 5.
Fig. 5. shews the floors of the top ovens, & how their heating is provided for.
A is the first cavity; about 12 inches square, & ten inches high. E is the centre
of of a coil of gas pipe flattened, or the seat (site?) of a vessel holding parafine.
b is the gas-pipe. L is a section of the gas pipe going up to the "ceiling,"
& running dingonally across this chamber, bending out of it into the posterior
chamber; & there taking the course of the dividing door when closed. [For all
this sec R in the next figure]. P is the dividing door. B is the right posterior
chamber. Fits gas-centre; a the pipe leading thereto. R is the flue between the
right & left sides. C is the third oven; G its gas centre; d the pipe supplying it.
M is part of the course of the gas-pipe that supplies the wall of this & the next
oven. (see Fig. 4. D.) D is the last of the four Divisions of the upper compart-
ment of the Sanitary Stove. H is the gas centre; e the pipe lending to it. P is
K is the outlet for the products of
the door dividing the two left side ovens.
combustion which descend thence to the winding flues cast on the inner sides of
the three outside plates of the stove. (see Fig. 9.)
Fig. 6. Represents a Section close to the "ceiling" of the four ovens occupying
the top of the stove. R shews the course of the roof gas-pipe-used for roasting.
It skirts along the large top plate piercing L shewn as it were in shadow here by
the dotted circle, for the section is really an inch lower down. [Nevertheless, the
chief points of the construction of this four chambered upper compartment of the
stove are here made very manifest-the piercings to let down culinary vessels L-
the doors N-the dividing hot air passage P-and the exit-corner whence the hot
air is received down into the winding flues for final discharge, K.-The main
roasting pipes R & M-and the direction of the air-currents indicated by the
arrows.] Continuing to describe the course of the main roasting pipe R which
is almost a semi circle, it enters the back oven in the interspace between the closed
door & the portion of fixed iron wall (flange) that completes the division of the two
ovens T; Thence it turns round, & runs close along the back of the door. M is the
roof gas-pipe left anterior oven in front of the top plate opening. (Sec Ee
in Fig. 4.)
Fig. 7. shews the floor & sides alike of the Boiler & of the Lower Oven, which
do not differ in the principle, & mode of construction & action, of their heating
floors A. The partition-walls dividing it into flues are C1. C2. C3: These
passages lead the flame current into the winding wall flues already described.
They enter at the corner E. In the largest division of this heating flour D
(which occupies ab ut half of the entire surfac.) the gas is laid on; or, in its
absence, a long parafine vessel is introduced; its mouth is closed with a slite, both
to command the air for combustion, & to admit of lighting. The hot air flues
surrounding the Boiler & Lower Oven are threefold. The first or primary set are
indicated by F. F. F. The hot air having wound around these (about 3 inches
wide cach, & one inch in depth) reaches the top of the oven or boiler, & thero
overflows into the residual hot air chamber; which constitutes the first coating (so
to speak) of blazing material by which the boiler & oven are heated. Where the
first series of flues terminates, the second begins. Into this the blaze opeus,
& proceeds along the secondary flues (of the same size) of course in a downward
direction till it reaches the point where the hot current first began to ascend from
the floor or furnace. H. H. H. mark the course of these secondary flues. The
tertiary or outermost flues (much deeper & wider than the others) now take up the

page_text: duty of disclarging the products of combustion; which are first made to wind
along the entire inside of the outer iron box that cases the stove. These larger
flues are marked K. K. K. see Fig. 9. C. for the point where the hot air from the
lower oven gets first into the outermost layer of flues; & for D the point where
the hot air from the boiler make its way into the same large outer series of flues.
The great ascending Blue (Fig. 9) F carries up the products of combustion in this
manner, & by this route, from the furnaces of the Boiler & Lower Oven, & pours
them into the top of the ascending outside back exit-flue at the corner *I* Fur
the point where these tertiary flues J terminate, & pour their hot steam into this
large exit-flue (that runs up the back of the stove) see the star Fig. 1. The same
point is indicated by the in the figure now under description (Fig. 7) which
plainly appears at the back of the stove (right hand side) & rising from the very
bottom, or foundation plate, of the stove.
Fig. 8. shows how the hot air flues on the walls of the right-side plate (of the first
series of flues, that is) are constructed. The arrows indicate their course. E is the
point where the blazing current first enters from the furnace flues at the bottom of
the oven. See also E in Fig. 7. where the arrows make this entrance very plain.
Fig. 9 illustrates, on the right hand outer wall-plate, how the hot air currents
from the Boiler & Lower Oven furnaces are led up to get into the direct chimney
exit. The general outside circulation cominences at the bottom of the upper oven
(see the outlet K in Figs 5 & 6. In other respects this figure has been sufliciently
explained in the details given of the constructive points of Fig. 7.
Fig. 10. shews the floor of the Hot Closet. Z is the lid of the Boiler. X X are
the floors of the two small side ovens. Y Y are the residual air flues that fill tho
bottoms, tops, & walls of the two sinall ovens. The back plate of this hot closet is
the right hand side wall of the right hand top oven. This wall, when the oven is
going," gets intensely hot. The hottest air, too, of the top oven overflows into
the residual air-chambers; & makes the hot closet hot enough for many culinary
operations; altho', in the present size of oven, we withhold, for the nonce, an
independent gas-supply.
Having now finished our description of the Sanitary Gas Cooking Stove, wo
make bold to affirm-(and we appeal to all competent judges how far we have
made out our case, & established our contention & pretention)-that we have
introduced a grand series of valid improvements in the apparatus for gas cooking
hitherto in vogue in any part of the world. The original, & novel, & "workable,"
& heat-saving, & health-saving devices of construction which I have instituted
differentiate iny stove from all rival stoves, as much as the make of the Henry-
Martini Rifle differentiates it from the "old brown bess." Look at my drawings
as contrasted with those of the construction of the best of the current gas
"cookers;" & it will scarcely be necessary to ask me to make the "points"
I have "scored" stronger, or more numerous than I have done.
Having now described particularly and ascertained the nature of my said
Invention, & in what manner the same is to be performed, I declare that what
I claim is
I. The system of heating the cavities, that is the ovens & boilers, by furnaces
contained in a double bottom, or a double top, precisely as in ordinary coal or coke
heated boilers, or furnaces for air heating & other purposes; but of course on a
very dwarf-scale of size, as demanded by the condensed, and more valuable, but
equally effective, fuel used. And that the heat so generated should not pas
immediately away by the nearest outlet to the atmosphere, as so much poison
to get quit of in the most summary way-as is deemed to be the wasteful necessity
of coal fuel-I establish a long series of small but sufficient flues for actively
circulating the burning products almost red hot, round & round the bottom
of the oven or boiler, & up in a series of close winding, all round its sides & back
& overflowing all the top surface in a chamber reserved for the purpose, & called
the Residual or Residential or overflow hot air cavity. The effect of all this
is equivalent to plunging a close iron square box, on five of its sides into the midst

page_text: of rodhot conls!!! In this way, the more precious fuel I deal with (mostly, but
I do not exclude other fuel) has its last possible degrees of caloric extracted before
evanishing for ever. And the more to ensure this effect, I establish a second series
of flues a repitition of the first-into which the first set of flues empty themselves.
And not content with this, I employ a third set, of double the capacity of either
flue No 1 or fluo No 2, to lead off finally (in the most circuitous way, all along the
massive outer walls of the stove) the products of combustion (collected from every
heating cavity) to be discharged up the chimney. There is, therefore, no escapo of
the noxious fumes into the cooking apartment, to poison withal Her Majesty's liege
subjects; as if security against this should not be made an Inventor's primary &
paramount object But the immense saving of fuel & of heat by this expedient is
so obvious that insisting upon it would be absurd. In all or most other cases, the
heat that has done its work upon the bottom & sides of a furnace or vessel has
done its work for ever; departs; is wasted; & of no more service.
All this the present Inventor claims as an entirely new & original thing in Gas-
heated, or oil, or spirit- heated cooking stoves. These, indeed, in a modified &
curtailed fashion, are found in some kitchen ranges, & "Cookers," and "Kitcheners,"
where coal or coke is the fuel. And, indeed, such flues are of the most ancient
origin. We borrow them from the far back times of the Roman Republic. But
I claim to be the first Inventor who has applied them, systematically to gas-heated,
or oil-, or spirit- heated cooking stoves. None of these rival stoves are heated from
the exterior, as I have heated mine. They all burn gas freely in their interior; &
try as best they can to diminish its evils by an immense waste of heat-by leaving
open bottoms, or gaping sides of ovens, to "ventilate" them too often at the
expense of overflowing the kitchen with the fumes!
1
In cases tried for the Infringement of Patent Rights, it has been held by
the consensus of legal opinion, that the first Introducer and Adapter of an old
principle for entirely new purposes, & in a new apparatus as a whole, was, to all
intents & purposes, an Inventor-to be protected, while a Patent lasts, in the new
thing he has given to the world.
II. Another new thing the Inventor of this stove introduces, is the System
of heating in special chambers & flues, & circulating by means of the same, & by
outlets at needed points, the air to be used for supporting combustion. Thereby
another obvious & immense saving of heat is effected. For this simple but
scientific novelty, the Inventor most respectfully throws himself under the wing of
the Patent Authorities !
III. The upper Division of this new stove is an entire novelty. There is first a
Bubdivision into a series of compartments (in size A. four such)-separate yet
connected cooking chambers, with hot air escapes or outlets from one compartment
to another; thus permitting each furnace to receive in succession the heating power
of its neighbour, & to transmit it almost unexhausted to the next cavity; & so
it finds its way (when no more can be done with it) to the outside flues on the
interior of the outside (or enclosing) plates of the stove; till it reaches, (by a most
circuitous route) the chimney exit.
In the next place; these ovens are equally adapted for boiling, or stewing, or
baking, or roasting, or grilling; & all this mutual convertibility of function, or
culinary office, is effected by simply fixing on the lids of the top-plate-piercings,
& lighting a new set of gas-pipes; or making an alteration of the parafine vessels.
These piercings for the admission of pots, or pans, or kettles, are entirely now
things in their nature & work, as I have adapted them. Thro' them the cooking
vessels descend to a depth of from three to five inches, more or less, into the
blazing furnace; making the heating effect & power equivalent to burying a pot,
or kettle, so many inches deep, among red hot coals! But where do we find this
sort of thing on our cooking coal fires; much less, in any of the existing gas
stoves ? Where, even, do we find pots & kottles, with appropriate flanges fitted to
hold them fixed in such sockets, & to exclude the smoke? The practice is, in both
instances, merely to put the bottom of the vessel upon the coals; or in the case of

page_text: gas, it is, as a rule, tilted bigh, usually one or two inches or more, above the burning
jets, with an open atmosphere of cold air, all round the sides, or walls of the vessel,
&& often a strong rush of it under them! The superiority, in heating effect, of
my unchilled cooking cavity, & the direct & close accumulation of caloric round
half the body of my pots & kettles (where economy of heating, in long culinary
processes, tells) is too apparent & transparent to need one word of comment.
A further entirely new feat & feature of invention in this top compartment (now
under description of the sanitary cooking stove-is the system of slides in the
bottom of its respective cooking cavities-one for each cavity-supplying the air
for combustion received up from the heating floor below. The use of this mode of
air-supply is optional, & the power to regulate its amount, or to cut the supply off
entirely, or to derive it otherwise, as need requires, is at once a great culinary
economy & convenience.
For
The above points, both individually, & as a series, of this upper Division of the
stove are without analogue or precedent in any gas, or other, Cooking Stove.
this upper Division, which will work perfectly efficaciously when detached from
the whole apparatus, the special aegis of the Patent Office is asked: on the ground,
that it is intended to make this stove, so detached, the grand culinary resource
& dependence of the working masses unable to buy any thing larger. It will, with
a great saving of fuel, do all ordinary cooking, and more than the best of the
present small kitchen ranges they use; & will come within the ability of their
purse, in good times. In any case, Gas companies will hire them out the. article
on a very moderate quarterly rate.
:
IV. The Boiler claims similar protection because its furnace & flue systems of
heating (as described in its place) are also without analogue or precedent in any
Gas cooking stove; or, for that matter, in any boiler yet made. We have boilers
surrounded with hot air, as it were enclosed in a box; but we have no boilers
where the products of combustion are carefully kept supplied to their sides, tops, &
bottoms, by a series of closely coiling flues which detain the heat to the longest
time possible; & then let it escape by dribblets (as it were) instead of rushing
away in the same large stream in which it was supplied. This also will work
perfectly well, detached from the apparatus of which it here forms a leading feature.
This also, made of several sizes, will be an immense Family Convenience in the
homes of the working man; & it is intended to be brought out as the associate―
yet independent and detached-of the cooking department (III) just described; &
to be put within equal reach of the working man. The entirely novel position
of the Builer in my stove; its relatively capacious size contrasted with its
insignificant capacity, & in fact its general entire absence, in rival stoves, are
conspicuous & exclusivo characteristics which shd bar infringement. But, as the
substitute for the "set pot;" as a means of preparing a warm bath in a few
minutes; & as fitted to meet all the claims of "the washing day," of the operative
class the Inventor respectfully urges his claim for its legal protection.
V. The massive solid iron box constituting the lower oven, & its associated
furnace & flues, & residual air chamber &c, as already described, & constructed on
precisely the same type as the Boiler-will also, one day, be detached, & set apart
for the convenience of the working man; as a necessity for bakers & pastry cooks
in a small or even in a large way; for public institutions; for ships at sea; for
armies in the field; & for the colonist & the squatter-this stove, sold detached,
will be a great public boon.
VI. The introduction of slides, instead of doors, for the ovens is a decided
improvement, & a notable novelty; as I have shewn in the proper place. The
optional substitution of strong massive plateglass, in one or both of the slides
either by way of the slide itself, or as a panel enhances this novelty. The light
so thrown into the interior may, or may not, be always equally serviceable. Stear
will mar its inspecting power; but independently of this, there are many
occasions in which a cook will obtain great help from the reconnoitring power of
the glass.

page_text: VII. The iron moulds or casts of the bottoms of the chief cooking vessels, when
suspended by their flanges into the depths of the red hot furnace-are entirely
original things, never so applied or thought of before. They get intensely hot, &
long retain that heat after gas or parafine is extinguished. A cooking vessel
plunged in this socket gains a great start in the boiling race; & where stewing
simply is required, a fresh reapplication of heat in the furnace may be much longer
dispensed with. In cases where the frames are apt to escape on withdrawing the
oven-lids or ono oven lid, they are effectual preventives of any escape of the
products of combustion into the apartment.
VIII. My modified Bunsen Burner is adapted to a new use, as convertible into a
simple air-conduit.
IX. A looking glass into the top ovens by a massive piece of glass either as a
slide, or a panel in a slide; also another with handle to it for temporarily sub-
stituting the lid of the piercings in the "top-plate "is an entire novelty; but every
cook will admit it to be an immense convenience for surveying the condition of her
comestibles within.
X. & lastly. For the mode of the final exit into the chimney of the products of
combustion: the relatively capacious ultimate flue attached at the back of the
cooking apparatus: for the slide in it, & the means of burning a small dish of
parafine, where it is an object, on beginning cooking, to activate the circulation
thro' the long series of winding flues detailed; & for the "throttle valve" at the
extreme exit;--for all these novelties legal protection is respectfully claimed.
:
In conclusion one parting word may be permitted to the Inventor in his
capacity of Physician & sanitarian. By preventing the extravagant waste of
carbon from coal fires, the extended use of this stove will pave the way-quantum
valeat for the ultimate extinction of-tho appalling & destructive smoke-nuisance
of modern towns. Professor Roberts calculates that the soot in the smoke-pall
hanging over London, on a winter's day, amounts to 50 tons: and the carbonic
oxide (a poisonous compound) resulting from the imperfect combustion of coal,
may be taken as at least five times that amount !
Dated this 10th day of December 1884.