IMPROVEMENTS IN GAS FIRES
Year: 1856

page_text: LETTERS PATENT to Nathan Defries, of Fitzroy Square, in the County
of Middlesex, and George Henry Bachhoffner, of Montague Street,, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN GAS
FIRES."
Scaled the 21st October 1856; and dated the 1st May 1856.
PROVISIONAL SPECIFICATION left by the said Nathan Defries and George
Henry Bachhoffner at the Office of the Commissioners of Patents, with
their Petition, on the 1st May 1856.
I, NATHAN DEFRIES, of Fitzroy Square, in the County of Middlesex, and
I, GEORGE HENRY BACHHOFFNER, of Montague Strect, in the County of
Middlesex; do hereby declare the 'nature of the said Invention for IMPROVE-
MENTS IN GAS FIRES, to be as follows:-
- Our Invention of improvements in gas fires consists, first, in forming the
gas burner or jets used for such fires of argillaceous material, mixed with oxide
of copper or other metallic oxides or metals in a finely divided state, which
imparts a hardness to the argillaceous material, and renders it more durable for
the purpose; and also has this advantage, that it produces the burner of a dark
or black colour, which, if of a suitable shape, gives it the appearance of coals:
We also form the compound of argillaceous matter and metallic oxides or
metals into small-thin masses or layers, having one or more openings through
aliem, and over which openings we place threads or films of asbestos, where they
are caused to adhere while the argillaceous matter is in a moist state. These

page_text: layers of argillaceous matter, thus composed, are placed above each other on the
burners emitting the gas, which in its emission & ignition causes the whole
mass to become ignited or red hot, & thus represents all the appearance of a
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Nathan Defries and George Henry Bachhoffner in. the Great
Seal Patent Office on the 1st November 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we NATHAN
DEFRIES, of Fitzroy Square, in the County of Middlesex, and GEORGE
HENRY BACHHOFFNER, of Montague Street, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of May, in the year of our Lord One
thousand eight hundred and fifty-six, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
Nathan Defries and George Henry Bachhoffner, Her special licence that we,
the said Nathan Defries and George Henry Bachhoffner, our exccutors,
administrators, and assigns, or such others as we, the said Nathan Defries
and George Henry Bachhoffner, our 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 Ireland, the Channel Islands, and Isle of Man, an Invention for "Im-
PROVEMENTS IN GAS FIRES," upon the condition (amongst others) that we, the
said Nathan Dofries and George Henry Bachhoffner, our executors or admini-
strators, by an instrument in writing under our, or one of our or their, or
one of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, 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 Nathan Defries, on behalf of myself and
the said George Henry Bachhoffner, do hereby declare the nature of our said
Invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
Our Invention of improvements in gas fires consists, first, in forming the
gas burner or jets used for such fires of argillaceous material, mixed with

page_text: oxide of copper or other metallic oxides or metals in a finely divided state,
which imparts a hardness to the argillaceous material, and renders it more
durable for the purpose; and also has this advantage, that it produces the
burner of a dark or black colour, which, if of a suitable shape, gives it the
appearance of coals.
We also form the compound of argillaceous matter and metallic oxides or
metals into small thin masses or layers, having one or more openings through
them, and over which openings we place threads or films of asbestos, where
they are caused to adhere while the argillaceous matter is in a moist state.
These layers of argillaceous matter, thus composed, are placed above each
other over the burners emitting the gas, which in its emission and ignition
causes the whole mass to become ignited or red hot, and thus represents much
the same appearance as coal fire.
Our Invention refers to an improved formation and arrangement of the
burners for gas fires, which is further applicable to the arrangement of gas
fire previously patented by us, the Patent being dated on or about the Nine-
teenth day of December, One thousand eight hundred and fifty, the Speci-
fication of which was duly filed in the Enrolment Office of Her Majesty's
High Court of Chancery; and also in the nature and preparation of the
noncombustible matter employed to give the appearance of a bright coal
fire, gas alone being the combustible agent.
In the construction of gas burners, for this purpose, we employ the well-
known substance called potters' clay, in a state or condition similar to that
employed by the potter in the fabrication of ordinary pottery, or the descrip.
tion of clays commonly known as pipe-clay and fire-clay; with either kind of
clay we mix from 10 to 15 per cent. (more or less) of any metallic oxide, or
borings of iron, or other metal, in a finely. divided state, not fusible at a red
heat, such as the black oxide of manganese, the black oxide of copper, the
per or sesqui oxide of iron, the metal platinum, in a minute state of division,
commonly known as spongy platinum, or the substance known as plumbago
or black lead, or it may be iron borings or filings. For these purposes we
give preference to the black oxide of copper, as it remains unchanged in
colour when mixed with the clay after being exposed for a length of time to
the action of the gas flame, while it gives to the clay the firmness and con-
sistency of a metallic substance, and at the same time affording, it a closer
and better resemblance to ordinary coal. The metallic oxide is kneaded up
with the clay, and when well incorporated we form with it the burner, our
mode of making which is as follows:-Having taken a pattern of the fire
grate into which the burner is to be fitted, the clay while in a plastic state is

page_text: moulded in two or more pieces upon the said pattern; the mould or core is
then removed, and the several pieces are united, in the ordinary way, so as
to form a hollow mass; a hole is then made beneath for, the admission of gas
and attachment of the gas. pipe. In the upper surface, and towards that
portion of the burner which is to form the front of the fire, and, from which
the gas to be ignited is to issue, fine holes are pierced, drilled, or moulded for
its emission. The burner, thus prépared, is then dried and fired in the kiln, as
now practised for ordinary pottery ware. Instead of a burner of this descrip-
tion from which the gas is emitted, we sometimes use hollow bars, of-the
prepared clay, which bars may be. so formed as to coincide with the bars of the
fire--grate. Holes are drilled or moulded in. these bars for the escape of the
gas, in manner similar to the iron bars now employed for that purpose... Other,
shapes and arrangements of burners may be formed of clay, combined with
oxides of metals, or metals in a finely divided state, as before, described, suited
and adapted to the purpose for which they are required.
We use the same combination of clay and oxides of metals, or metals
herein-before described as employed in the construction of the burner, in the
formation of thin lamina, in pieces of an area from about one to sixteen square
inches, and of about one-eighth to one-sixteenth of an inch in thickness, more
or less. While in a plastic state holes or perforations are made through such
pieces, by preference without regularity of order or position.. Over these holes
filaments or strips of asbestos are placed, and caused to adhere while the clay
is yet in a plastic state, and to which the asbestos adheres when the lamina or
thin masses of clay are baked and fired, or burnt in a kiln as before described.
The plates or laminæ of clay are moulded of a convexo-concave form, so that
gas on being admitted below the under and concave side will pass up through
the holes, and will impinge on and pass through amongst the filaments of
asbestos in. an ignited state.
.In any suitable fire-place or position we place the burner from which the
gas is emitted; superposed on this we place several layers of the pieces of clay
before. mentioned, with the concave side downwards, so that the gas, when
emitted and lighted, passes up through the several layers or laminæ of the clay
and asbestos. Immediately the gas is lighted the asbestos presents a bright
luminous appearance, while the clay presents more or less the appearance of
black coals. After the gas has been lighted some little time it gradually
becomes red hot, and will become more or less, or entirely so,, according to
the quantity of gas consumed, in proportion to the extent and arrangement of
the clay, any part remaining dark or black resembling in some degree the
black coals of a fire...
4.

page_text: The several parts, manufactured as herein-before described, are applicable,
and may be arranged and applied in the manner of the gas fires, described in
the Specification of our former Patent, herein-before referred to.
Having described the nature of our Invention, and the manner in which
the same may be performed, we would have it understood that we do not claim
the exclusive use of clay or other argillaceous materials, or asbestos alone, in
or as part of gas fires, or of the gas burners for those fires; but that what we
do claim as of our Invention, and to be secured by the berein-before in part
recited Letters Patent is, the combination of the metallic oxides or metals,
berein-before mentioned, with clay or argillaceous materials, in the manu-
facture of gas burners or the parts of gas fires. We also claim combining
and arranging filaments of asbestos with the layers or masses of the clay, as
herein-before described.
In witness whereof, I, the said Nathan Defries, have hereunto set my
hand and seal, this Thirty-first day of October, in the year of our Lord
One thousand eight hundred and fifty-six.
Witness,
WILLIAM CLARK,
Patent Agent,
53, Chancery Lane, London.
N. DEFRIES. (L.S.)