IMPROVEMENTS IN LAMPS
Year: 1872

page_text: LETTERS PATENT to George Grainger Tandy, of Penge, in the County
of Surrey, Gentleman, and John Andrews Dryden, of Battersea, in
the same County, Lamp Maker, for the Invention of "IMPROVEMENTS
IN LAMPS."
Sealed the 6th August 1872, and dated the 1st March 1872.
PROVISIONAL SPECIFICATION left by the said George Grainger Tandy
and John Andrews Dryden at the Office of the Commissioners of
Patents, with their Petition, on the 1st March 1872.
We, GEORGE GRAINGER TANDY, of Penge, in the County of Surrey,
Gentleman, and JOHN ANDREWS DRYDEN, of Battersea, in the same
County, Lamp Maker, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN LAMPS," to be as follows:-
The object of our Invention of improvements in lamps is to obtain
brilliancy and steadiness of light when burning combustible liquids
(more especially those rich in carbon, such as petroleum and paraffin)
without using a glass chimney or globe or any transparent substitute
for regulating or controlling the flame.

page_text: In carrying out our Invention we enclose the burner within a jacket
or envelope partly or entirely of glass as is usual in railway lamps, but
we are careful to render this envelope air-tight at its upper edge, and
we admit the air to the burner by special channels provided for the
purpose, as will be hereafter explained.
Our Invention is more particularly applicable to railway carriage
roof lamps, but can be adapted to other lamps, such as swinging lamps
or other lamps or lanterns. In railway carriage roof lamps the burner
consists of an oil cup or chamber to hold the wick, and is provided
with a metal dome to enclose or encircle the wick. This burner is
placed at the bottom of the enveloping glass dish, on the upper edge of
which is carefully fitted the reflector so as to prevent any ingress of air
to the flame except through the proper channels. From the space above
the reflector and which communicates with the external atmosphere two
tubes conduct the air to the interior of the burner in order to support
combustion, and all access of air to be burner except through these
channels is carefully prevented. The outer orifices of these tubes are
protected by means of wire gauze or perforated metal from the effects
of external currents of air, so that the supply of air may be uniform and
steady. The oil is contained in an annular or semi-annular reservoir
placed outside the lamp so as to keep the same cool, and two tubes lead
down from it to the burner. The reflector has a piece cut out of the
centre, and to this detachable part of the reflector is attached a metal
chimney for creating sufficient draught through the burner. The object
of this part being detachable is merely to facilitate the lighting of the
lamp. In order to increase the up-draught we make this metal chimney
rather longer than usual.
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 31st August 1872.
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 Battersea, in the same County, Lamp
Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of March, in the year of our

page_text: Lord One thousand eight hundred and seventy-two, in the thirty-fifth
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 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
wo, the said George Grainger Tandy and John Andrews Dryden, exe-
cutors 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 Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that we, the said George Grainger Tandy and 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) :—
The object of our Invention of improvements in lamps is to obtain
brilliancy and steadiness of light when burning combustible liquids
(more especially those rich in carbon, such as petroleum and paraffin)
without using a glass chimney or globe or any transparent substitute for
regulating or controlling the flame.
In carrying out our Invention we enclose the burner within a jacket
or envelope partly or entirely of glass as is usual in railway lamps, but
we are careful to render this envelope air-tight at its upper edge, and we
admit the air to the burner by special channels provided for the purpose,
as will be hereafter explained.
Our Invention is more particularly applicable to railway carriage roof
lamps, but can be adapted to other lamps, such as swinging lamps or
other lamps or lanterns. In our improved railway carriage roof lamps

page_text: the burner consists of an oil cup or chamber to hold the wick, and is
provided with a metal dome of peculiar form or construction which
encloses or encircles the wick. This burner is placed at the bottom of
the enveloping glass dish, on the upper edge of which is carefully fitted
the reflector so as to prevent any ingress of air to the flame except
through the proper channels. From the space above the reflector and
which communicates with the external atmosphere two tubes conduct
the air to the interior of the burner in order to support combustion, and
all access of air to the burner except through these channels is carefully
prevented. The outer orifices of these tubes are protected by means of
wire gauze or perforated metal from the effects of external currents
of air, so that the supply of air may be uniform and steady. The oil is
contained in a reservoir placed outside the lamp so as to keep the same
cool, and two tubes lead down from it to the burner. The reflector
has a piece cut out of the centre, and to this detachable part of the
reflector is attached a metal chimney for creating sufficient draught
through the burner. The object of this part being detachable is merely
to facilitate the lighting of the lamp. In order to increase the up-
draught we make this metal chimney rather longer than usual.
In the accompanying Drawings Fig. 1 is a vertical section, and Fig. 2,
a sectional plan view of one of our improved railway carriage roof
lamps.
a, a.
a, a, is the ordinary enveloping glass, in which the burner of the
lamp is placed, and c, o¹, is a reflector made of bright metal or other
suitable material; it is formed of two parts c and c¹. The outer part
c is made of an annular form and is fixed to the oil and air pipes and g,
hereafter described, and fits closely on the top edge of the glass envelope
The central part c¹ of the reflector carries a metal chimney c².
It rests on a ledge formed round the inner edge of the annular part c,
and may be lifted out without disturbing the other part. The oil
reservoir d, d, is made of a curved or semicircular form and is placed
outside the metal case e, e, of the lamp. This reservoir a communicates
with the burner below by means of the two tubes f, f¹, the upper end of
one of which f¹ passes through the bottom of the reservoir and is carried
up to the top of the oil space, as indicated by dots in Fig. 1, so that as
the oil passes down the tube f to the burner air will pass up the tube
finto the oil reservoir. All the air to support combustion is drawn in
from outside the lamp and passes down the tubes g, 9, and is conveyed
thereby to the spaces i, i, (Fig. 3) on each side of the wick holder, from

page_text: whence it rises up to the space between the wick holder and the dome
or deflector h, whereby it is thrown on to the flame near the point of
ignition. The oil supply pipes f, f¹, are placed behind the air tubes g, g,
so as to protect the same from the direct radiation of heat from the flame.
The open ends of the air tubes are protected from sudden puffs of air by
wire gauze or perforated metal shields. The wick holder j is of a flat
form and of the ordinary construction, and is enclosed within a metal
dome h, which acts as a deflector. We find by experience that the
construction and form of this dome or deflector is of great importance
for the successful action of the lamp, and in order that its construction
may be clearly understood we have shewn at Figures 3, 3a, and 36
various views of it detached; Figures 3 and 3a being vertical sections
taken at right angles to each other, and 36 a plan view of the interior
shewing the air spaces i, i, and oil or wick chamber j¹. It will be seen
that the inclined sides of the deflector / are flat and the slit or opening
(through which the flame passes) is perfectly level and is not cut down
at the ends. The ends of the dome also are perfectly vertical so that the
air will only impinge at an angle on the sides of the flame and not at
the ends, and the flame will therefore be straight instead of fan-shaped
or spreading as is usually the case. It will be seen moreover on referring
to the plan view that the wick is placed at right angles to the vertical
plane of the oil and air tubes, and therefore these will throw no shadow
from the transverse flat flame. As the burner, the oil reservoir, and
oil and air tubes, and the part c of the reflector are all connected
together they may all be lifted at once from the envelope or case a, and
in order to prevent the lamp from shaking about on its seat, it is steadied
by means of the blocks k, k, on which the top or cover of the envelope
presses when in its place and the lamp is shut.
Fig. 4 is a vertical section, and Fig. 5 a plan view of a modification of
the lamp shewn at Figures 1 and 2. In this instance the oil tubes are
placed inside the air tubes and the wick holder is arranged in the samo
vertical plane as the air and oil tubes. This arrangement of parts will
be found convenient for use in third class carriages or other carriages
where the light is required to be thrown across several adjoining com-
partments.
Although in the Drawings we have only shewn our Invention as
adapted to railway carriage roof lamps, it will be evident that the same
principle of construction is equally applicable to ships' lamps, signal
lamps, carriage lamps, and street and other stationary lamps in which

page_text: hydrocarbon oils are usually consumed.
The essential features of the
Invention will be the same in all cases, but the form and construction
of the envelope or casing must be varied according to the circumstances
of the case for which the lamp is to be used.
Having now described our Invention of "Improvements in Lamps," and
having explained the manner of carrying the same into effect, we claim
as the Invention secured to us by Letters Patent as aforesaid, constructing
carriage, roof, and other lamps, including ships' and signal lamps and
street or stationary lamps in which hydrocarbon oils are usually
consumed, substantially in the manner or manners herein set forth.
We claim particularly the combination of a burner which is supplied
with oil and air to support combustion by means of special tubes arranged
as herein set forth, with an oil reservoir outside the envelope or casing
of the lamp, as above shewn and described.
We also claim constructing the dome or deflector in the manner and
for the purpose herein set forth.
In witness whereof, we, the said George Grainger Tandy and John
Andrews Dryden, have hereunto set our hands and scals, the
31st day of August, in the year. of our Lord One thousand cight
hundred and seventy-two.
G. G. TANDY.
(L.S.)
J. A. DRYDEN. (L.S.)