.AN IMPROVED SILICA GAS STOVE
Year: 1873

page_text: LETTERS PATENT to Joseph Coultas Akester, of Hull, in the County
of York, Chemist, for the Invention of ".AN IMPROVED SILICA GAS
STOVE."
Sealed the 10th March 1874, and dated the 19th December 1873.
PROVISIONAL SPECIFICATION left by the said Joseph Coultas Akester
at the Office of the Commissioners of Patents, with his Petition, on
the 19th December 1873.
I, JOSEPH COULTAS AKESTER, of Hull, in the County of York, Chemist,
5 do hereby declare the nature of the said Invention for "AN IMPROVED
SILICA GAS STOVE," to be as follows:-
-
The Invention consists in utilizing the heat of gas issuing in an ignited
state from Bunsen's or other suitable burners by passing it through silica
in the form of pumicestone enclosed in a perforated case, by which
0 means stoves, ovens, cooking apparatus, boilers, et cetera, may be heated
with less than half the usual consumption of gas.
Construction of the Stove.-The apparatus consists of two cylindrical
chambers arranged one within the other concentrically. The internal

page_text: chamber is perforated or grated at top and bottom, so as to communicate
with the atmosphere. The external chamber is also perforated at top
and bottom for a similar purpose, and is subdivided by an annular
perforated diaphragm in a plane perpendicular to the axis of the
concentric cylinders. The upper of these sub-divisions is filled with
pumicestone. The lower division contains a circle of burners (which
may be a simple tube bent into a ring with perforations for burners)
supplied with gas by a pipe passing through the outer casing of the
stove. The side of this sub-chamber is perforated to admit atmospheric
air, and to enable the burners to be lighted with facility.

page_text: Advantages of the Stove.-1. The heat from the ignited gas is
absorbed by the silica, and thence radiated in a uniform manner; 2, the
products of combustion in passing over the extended calid surface of the
finely cellular pumicestone are deprived of their unconsumed carbon,
which unites with some of the oxygen of the excess of of atmospheric air
admitted to the silica chamber. By these means the gases upon escaping
are free from smell and smoke, and an additional heat is derived from
the secondary combustion. The result is that a greater quantity of
heat can be obtained from each cubic foot of gas consumed in this
apparatus than from any other system at present known. A stove eight
inches diameter by sixteen inches high, with a consumption of three
cubic feet of gas per hour, has been found to sustain at sixty degrees of
Fahrenheit a room fourteen feet by eleven, the temperature outside the
house being twenty-seven degrees.
Features of Novelty in the Stove.-The Inventor claims as his Inven-
tion the use of silica in the form of pumicestone in apparatus for
heating by gas, constructed in accordance with this Specefication.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Coultas Akester in the Great Seal Patent
Office on the 17th March 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
COULTAS AKESTER, of Hull, in the County of York, Chemist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninteenth day of December, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Coultas Akester, Her special
license that I,,the said Joseph Coultas Akester, my executors, administra-
tors, and assigns, or such others as I, the said Joseph Coultas Akester,
my 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 vend, within the United Kingdom of Great Britain and

page_text: .
Ireland, the Channel Islands, and Isle of Man, an Invention for "AN
IMPROVED SILICA GAS STOVE," upon the condition (amongst others) that I,
the said Joseph Coultas Akester, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands & 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 I, the said Joseph Coultas Akester, do hereby
declare the nature of the said Invention, and in what manner the same 1
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say:―
The Invention consists in utilising the heat of gas issuing in an ignited
state from Bunson's or other suitable burners by passing it through
*silica in the form of pumicestone enclosed in a perforated case, by which 1
'means ovens, stoves, cooking apparatus, boilers, et cetera, may be heated
with less than half the usual consumption of gas.
Advantages of the Stove.-Uniform distribution of heat and complète
combustion of the gas, by which great economy and total freedom from
smell and smoke are attained. A stove 8" diameter and sixteen 2
inches high, with a consumption of three feet of gas per hour, has been
found to sustain at sixty degrees Fahrenheit a room fourteen feet by
eleven feet, the temperature outside being twenty-seven degrees.
Features of Novelty in Stove.-The Inventor claims as his Inven-
tion, the use of silica in the form of pumicestone in apparatus for heating 2
by gas constructed in accordance with this Specification, that is to say,
the use of silica in a suitable perforated case.
Form of Stove suitable for Heating Rooms, et cet.-Two cylindrical
chambers are arranged one within the other concentrically. The internal
chamber is perforated or grated at top and bottom, so as to communicate
with the atmosphere. The external chamber is also perforated at top
and bottom for a similar purpose, and is subdivided by annular per-
forated diaphragms in a plane perpendicular to the axis of the concentric
cylinders. The upper of these sub-divisions is filled with pumicestone.
The lower division contains the system of burners, which may be of any a
form or arrangement suitable, supplied with gas passing through the
outer casing of the stove. It is also furnished with a metallic reflector

page_text: -
of corrugated metal. This form of stove is represented in Figs. 1, 2, 3, 4,
5, 6, 7 of the annexed Drawings. Fig. 1 is a side elevation; Fig. 2, a
vertical section of same.
-
Details A, outer casing; B, rivited brackets to sustain diaphragm;"
C, lower perforated diaphragm; C₁, upper do., resting on silica; D, inner
tube or casing fastened into C; E, cast-iron perforated top; F, cast-iron
bottom; G, gas burner and tube; H, metallic reflector; I, square block
on annular bottom to admit gas tube; S, silica. Fig. 3 is a plan of the
top of the stove. K, K, et cet., are circular openings for the escape of
the torrefied air; and L, the mouth of the central caliduct. Fig. 4 is a
plan of the bottom of the stove, which is an annulus (P, P,) of metal,
rebated to accommodate the outer casing; I, is the arrangement for the
admission of gas tube. Figs. 6 and 7 are vertical sections at F and I.
Fig. 5 is a plan of the perforated diaphragms, showing the grating M, M,
et cet., and the circular opening N.
Action of this Form of Stove.—It is lighted by lifting the outer casing
away from the cast-iron bottom, on which remains the gas tube and ring
burner, as also the reflector. The stove is then replaced on the bottom.
The gas travels through the tube G into the system of burners C. The
flame plays below the perforated diaphragm C¹; the heat ascends to the
pumicestone S, which becomes intensely hot. By these means the air
included by D undergoes calescence, and a current is established, which
escapes by the perforations in the top of the stove.
A form of stove adapted for ovens, et cet., is represented in Figs. 8, 9,
10, 11, 12; Fig. 8, a vertical section of same; Fig. 9, a plan of top;
Fig. 10 is a transverse section, shewing construction of inner case, which
is dropped into its place from top of oven; Fig. 11, a plan of the system
of burners; Fig. 12 a front elevation.
Details. A, brackets to support a shelf; B, the shelf or upper
) oven. The part on which the silica rests is perforated to permit
the hot air to pass upwards. C, an inner casing of sheet iron at two
sides, back and top of oven; D, silica; E, brackets; F, moveable
shelves; G, burner; H, a tube admitting cold air from outside. The air
passes through a number of small holes in the tube, and supplies the
5 flames; K, K, effluent caliducts.
The forms of stove described above fully illustrate the Invention
applied in practice, but the Inventor claims the privilege of using such

page_text: purposes of
modifications of form and arrangement as may be suggested by special
circumstances in the adaptation of the stove to the various
cooking, heating baths, warming greenhouses, et cet. Such modifications
are too obvious to need description here, as they will naturally suggest
themselves to the mind of every stove engineer.
Having now particularly described and ascertained the nature of the
said Invention, I claim as the subject of these Letters Patent, the use of
silica in the form of pumicestone in apparatus for heating by gas con-
structed in accordance with this Specification.
In witness whereof, I, the said Joseph Coultas Akester, have here-
unto set my hand and seal, this Sixteenth day of March, in
the year of our Lord One thousand eight hundred and seventy-
four:
JOSEPH COULTAS AKESTER.
(L.S.)