AN IMPROVED VENTILATING GAS. LAMP OR GASALIER
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by James France Hill at the Office
of the Commissioners of Patents, with his Petition, on the 21st August
1863.
I, JAMES FRANCE HILL, of 23, Little St. Andrew Street, Upper St. Martin's
Lane, London, do hereby declare the nature of the said Invention for "AN
IMPROVED VENTILATING GAS. LAMP OR GASALIER," to be as follows:-
My Invention consists generally of a gas light supported by a bracket or
pendant tube enclosed within a shade or covering consisting of two parts, and
composed of transparent or semi-opaque or partly transparent and partly semi-
opaque glass or other suitable material. The surfaces of the material of this
shade or covering are of such a nature as to possess at the top & sides a
greater power of reflection than of radiation, and at the bottom a greater
power of radiation or transmission than of reflection of light, thus ensuring the
greater portion of the light being thrown downwards while allowing a sufficient
quantity to pass upwards to illuminate the walls & ceilings. The two portions
of which this shade consists enclose the flame itself in such a manner as to
prevent the rays of light coming into direct contact with the eye at any point
while admitting at the point of junction between them an ample supply of air
to support the combustion. To each of such lights I supply a separate and
distinct ventilating tube so fixed to the top portion of the shade, or covering
and communicating with any convenient air shaft or outlet as that it infallibly
conducts away all the impure products of combustion and renders it simply
impossible for the light to have any deteriorating effect on the atmosphere of

page_text: the apartment; I further ventilate the body of the apartment by means of
openings in the wall or ceiling surrounding the tube or tubes which carry the
lights.
In further illustration of my object I append a mode of construction of one
such lamp to hang from the ceiling, but I desire it to be understood that I
reserve to myself the option of using such lamps either singly or in groups of
auy form & number that circumstances may render desirable; and also that I
do not confine myself to any particular description of burner, nor to any
definite size, form, colour, or material of the semi-opaque medium forming the
shade or covering of such lamps. I first fix in the ceiling a perforated plate
of any desirable design, size, or pattern, to the upper part of which I attach a
tube to form an air flue, and this I make to terminate in any adjacent chimney
or other suitable and convenient outlet to the open air. From the centre of
this plate I suspend two tubes of different diameters one within the other; the
inner one being the gas tube terminating in the burner, the outer one the
ventilating tube terminating at a suitable distance above it to receive the
products of combustion, and carry them up into the air shaft with which its
upper end is in communication. The outer tube is made of a sufficient
diameter to answer this purpose. Over the burner and supported by the tube
or tubes, I now fix. an opal or glass cover or shade in such a manner as to
allow of no opening at the top excepting one into the ventilating tube. This
shade surrounds the light in all directions excepting at the bottom. Under-
neath the open bottom I now fix a dish or plate of glass or any other suitable
transparent or semi-transparent material in such a manner as to be capable of
being raised to a point sufficiently near the top glass to prevent the flame
within from being directly seen, and lowered to such an extent as to admit air
to the burner, and to answer as a door for obtaining access to the interior of
the lamp for lighting, cleaning, or other purpose. In arranging such lamps
groups of two or more, as well as in adapting single lamps under varying
circumstances, modifications of these details will become necessary, but the
principle of construction of each lamp will in all cases be the same.
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