IMPROVE- MENTS IN THE CONSTRUCTION OF CHIMNIES POR LAMPS OR APPARATUS POR TRANSMITTING LIGHT
Year: 1860

page_text: LETTERS PATENT to George Henry Birkbeck, of the Firm of Tongue and
Birkbeck, of 34, Southampton Buildings, Chancery Lane, in the County of
Middlesex, Patent Agents and Engineers, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION OF CHIMNIES POR LAMPS OR APPARATUS POR
TRANSMITTING LIGHT."-A communication from abroad by Etienne Soulié,
Manufacturer, of Paris, in the Empire of France.
Sealed the 18th December 1860, and dated the 23rd July 1860.
PROVISIONAL SPECIFICATION left by the said George Henry Birkbeck
at the Office of the Commissioners of Patents, with his Petition, on the
23rd July 1860.
I, GEORGE HENRY BIRKBECK, of the Firm of Tongue and Birkbeck, of 34,
Southampton Buildings, Chancery Lane, in the County of Middlesex, Patent
Agents and Engineers, do hereby declare the nature of the Inventor for
"IMPROVEMENTS IN THE CONSTRUCTION OF CHIMNIES FOR LAMPS OR APPARATUS FOR
TRANSMITTING LIGHT," to be as follows:-
This Invention has for its object the construction of the chimnies of lamps
or other apparatus for transmitting light, partly of metal and partly of glass,
mica (tale), crystal, or other transparent or diaphonous substance.
For this purpose the upper and lower portions of the chimney of a lamp or
other apparatus employed for transmitting light is formed of any suitable
metal not liable to be melted by the beat from the lamp, the upper and lower
parts of such chimnies being connected together by narrow metallic rods or

page_text: connections opposite the flame of the lamp, so as not to intercept the light,
and the space between the upper and lower parts of metallic chimnies con-
structed according to this Invention is closed up or formed of glass, mica
(tale), or other suitable transparent substance, which may be of tubular or
other form in one or more parts, and supported on a suitable ring or gallery
on the lower part or body of the metallic chimney.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Henry Birkbeck in the Great Seal Patent Office_on
the 23rd January 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HENRY BIRKBECK, of the Firm of Tongue and Birkbeck, of 34, Southampton
Buildings, Chancery Lane, in the County of Middlesex, Patent Agents and
Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of July, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said George Henry Birkbeck, Her special licence that I, the said
George Henry Birkbeck, my executors, administrators, and assigns, or such
others as I, the said George Henry Birkbeck, 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 Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF CHIMNIES FOR LAMES OR
APPARATUS FOR TRANSMITTING LIGHT," a communication to me from abroad by
Etienne Soulié, Manufacturer, of Paris, in the Empire of France, upon the
condition (amongst others) that I, the said George Henry Birkbeck, my exec-
utors or administrators, by an instrument in writing under my, 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
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 George Henry Birkbeck, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention has for its object the construction of the chimnies of lamps
or apparatus for transmitting light, partly of metal and partly of glass, mica,
(tale), crystal, or other transparent or diaphonous substance.
For this purpose the upper and lower portions of the chimney of a lamp or
other apparatus employed for transmitting light is formed of any suitable
metal not liable to be melted by the heat from the lamp, the upper and lower
parts of such chimnies being connected together by narrow metallic rods or
connections opposite the flame of the lamp, so as not to intercept tho light,
and the space between the upper and lower parts of metallic chimnies con-
structed according to this Invention, is closed up or formed of glass, mica
(talc), or other suitable transparent substance, which may be of tubular or
other form, in one or more parts, and supported on a suitable ring or gallery
on the lower part or body of the metallic chimney.
And in order that the Invention may be most fully understood and readily
carried into practice, I will proceed to describe the Drawing hereunto

page_text: ment of the parts by which the cylindrical talc or mica may be enclosed between
the two divisions of the base or body B of the apparatus, a free passage being
formed for introducing the transparent material to form the gallery, which is
previously bent or formed into a suitable shape for this purpose. In the
arrangement shown at Figure 4 the part B of the chimney where the gallery
is placed is shaped to four equal angles of a parallelopiped, as seen in hori-
zontal section. The transparent gallery being formed by four plane rectangular
equal surfaces C, of glass, mica (tale), crystal, or other transparent diaphonous
substance fitting neatly and tightly, and placed in position through the lower
part in the angles B, as shown; or the plane transparent surfaces C may be
retained in position to form the gallery in a metal frame, as shown at Figures
1 and 2, and combined together into square, polygonal, or other suitable forms,
if desired.
In place of connecting the parts A, B, and B', together, as shown in the
Drawing, they may be connected by setting or closing the metallic parts upon
or over the edges of the transparent portion or gallery, or by other convenient
means.
Chimnies of lamps constructed according to this Invention may, like ordinary
lamp glasses, be suitable for having a shade or reflector applied thereto, as
shown in red lines at Figure 1, a ring b, such as shown in Figure 3, serving
to carry the foot c of this additional piece.
Having thus described the nature of the Invention, I would have it under-
stood that the same is not limited to the exact details herein described, so long
as the peculiar character of the Invention be retained, which consists in con-
structing the chimnies of lamps, gas burners, or similar apparatus for trans-
mitting light, partly of metal and partly of glass, mica (tale), crystal, or other
transparent or diaphonous substance, as herein described.
In witness whereof, I, the said George Henry Birkbeck, bave hereunto
set my hand and seal, this Twenty-third day of January, One thousand
eight hundred and sixty-one.
Witness,
J. G. TONGUE, Patent Agent,
34, Southampton Buildings,
Chancery Lane, W.C.
G. H. BIRKBECK. (L.S.)