IMPROVEMENTS IN LAMPS."
Year: 1874

page_text: LETTERS PATENT to George Grainger Tandy, of Penge, in the County
of Surrey, Gentleman, and John Andrews Dryden, of Corunna Road,
Stewarts Lane, in the same County, Lamp Maker, for the Invention
of "IMPROVEMENTS IN LAMPS.""
Sealed the 1st December 1874, and dated the 4th June 1874.
PROVISIONAL SPECIFICATION left by the said George Grainger Tandy
and Jolin Andrews Dryden at the Office of the Commissioners of
Patents, with their Petition, on the 4th June 1874.
We, GEORGE GRAINGER TANDY, of Penge, in the County of Surrey,
Gentleman, and JOHN ANDREWS DRYDEN, of Corunna Road, Stewarts.
Lane, in the same County, Lamp Maker, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN LAMPS," to be as follows:-
Our Invention of improvements in lamps relates to that class of
lamps in which liquid hydrocarbons are consumed for illuminating
purposes, and is more particularly applicable to railway roof lamps.

page_text: The object we have in view is. so to construct these lamps that the
supply of air to the interior of the lamp may be adjusted to the require-
ments of the case, so that the height of the flame and consequently the
consumption of oil may be regulated with accuracy and facility. This
will be found a great advantage and will effect a considerable economy,
inasmuch as the flame may be reduced in size when the light is not
required, and may be increased again in illuminating power when required
as when passing through tunnels.
In carrying out our Invention and adapting it to railway roof lamps
we cause the reflector to rest upon a moveable supporting piece at the
lower end of a rod which is screwed at its upper end and passes through
a nut, so that by turning the latter the reflector may be lifted a little
off its seat and air allowed to pass into the interior of the lamp and act
upon
the flame. Air is admitted to the interior of the burner through
a tube specially provided for the purpose, but no provision is required
for regulating the supply of air through these channels.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Grainger Tandy and John Andrews Dryden
in the Great Seal Patent Office on the 4th December 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE
GRAINGER TANDY, of Penge, in the County of Surrey, Gentleman, and
JOHN ANDREWS DRYDEN, of Corunna Road, Stewarts Lane, in the same
County, Lamp Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of Junc, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said George Grainger Tandy and John Andrews
Dryden, Her special licence that we, the said George Grainger Tandy
and John Andrews Dryden, our executors, administrators, and assigns,
or such others as we, the said George Grainger Tandy and John
Andrews Dryden, 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

page_text: 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 LAMPS," upon the condition (amongst
others) that we, the said George Grainger Tandy and John Andrews
5 Dryden, our executors or administrators, by an instrument in writing
under 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 performed, and cause the same to be filed
in the Great Scal 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 Grainger Tandy, on behalf
of myself and the said John Andrews Dryden, 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, reference being had to the Drawing hereunto
annexed, and to the letters and figures marked thereon (that is to .
say):
Our Invention of improvements in lamps relates to that class of lamps
in which liquid hydrocarbons are consumed for illuminating purposes,
and is more particularly applicable to railway roof lamps.
The object we have in view is so to construct these lamps that the
supply of air to the interior of the lamp may be adjusted to the require-
ments of the case, so that the height of the flame and consequently the
consumption of oil may be regulated with accuracy and facility. This
will be found a great advantage and will effect a considerable economy,
inasmuch as the flame may be reduced in size when the light is not
required, and may be increased again in illuminating power when
required (as when passing through tunnels) by simply regulating the
supply of air to the interior of the lamp casing.
In carrying out our Invention (and adapting it to railway roof lamps)
we cause the reflector to rest upon a movable supporting piece attached
to the lower end of a rod which is screwed at its upper end and passes
through a thumb nut, so that by turning the latter the reflector may be
lifted a little off its seat, and air allowed to pass into the interior of the lamp
and act upon the flame. Air is admitted from the casing to the interior
of the burner through a tube specially provided for the purpose, but no
provision is required for regulating the supply of air through these

page_text: cbannels, the adjustment of the air supply being confined to its admission
to the casing of the lamp from the external atmosphere.
The Figure in the accompanying Drawing represents a vertical
section of a railway carriage roof lamp with our improvements adapted
thereto. a, a, is the reflector of the lamp and is supported on one side
by the movable piece b, which is attached to a rod or strip of metal c
which passes upwards and is firmly attached to a forked piece or staple d;
e is a fixed screw on which works the thumb nut which takes into the
staple d; 9, 9, are the air tubes communicating with the interior of the
casing and through which the air is supplied to the interior of the
burner a*; h, h, are the oil tubes for supplying the wick with oil from
the annular reservoir *. In order to regulate the height of the flame
and consequently the consumption of oil it is only necessary to turn the
thumb nut f, and thereby raise or lower the movable piece 6 which
supports the reflector. This will permit the air to enter the interior of
the lamp through the small space below b, in such quantities as may be
required.
Having now described our Invention of "Improvements in Lamps,"
and having explained the manner in which it is to be carried out, what
we claim as the Invention secured to us by Letters Patent is, adapting
to the reflector a any suitable mechanical device (such for instance as
that above shown and described), whereby such reflector may be slightly
lifted off its seat when required, so as to admit a regulatable quantity of
air from the outside to the interior of the lamp glass, as and for the
purpose
herein set forth.
In witness whereof, I, the said George Grainger Tandy, have
hereunto set my hand and seal, the Fourth day of December,
in the year of our Lord One thousand eight hundred and seventy-