IMPROVEMENTS IN OIL LAMPS, AND IN REFLECTORS FOR THE SAME, FOR RAILWAY CARRIAGES AND OTHER PURPOSES." PROAL
Year: 1856

page_text: LETTERS PATENT to Alexis Jean Dessales, of 13, Rue des Enfants Rouges,
Paris, in the Empire of France, and of 43, Southampton Buildings,
Chancery Lane, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN OIL LAMPS, AND IN REFLECTORS FOR THE SAME, FOR
RAILWAY CARRIAGES AND OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Alexis Jean Dessales at
the Office of the Commissioners of Patents, with his Petition, on the
25th January 1856.
I, ALEXIS JEAN DESSALES, of 18, Rue des Enfants Rouges, Paris, in the
Empire of France, and of 43, Southampton Buildings, Chancery Lane, in
the County of Middlesex, do hereby declare the nature of the said Invention
for IMPROVEMENTS IN OIL LAMPS, AND IN REFLECTORS FOR THE SAME, FOR RAILWAY
CARRIAGES AND OTHER PURPOSES, to be as follows:-
My improvements in oil lamps, and their reflectors, refer principally to lamps
for lighting railway and other carriages from the roof, but also applicable to
similar lighting purposes, such as the cabins of ships, where the lamp is inserted
through the deck, and the light required to be generally diffused.
I form the reflectors circular, with a reflecting surface somewhat like a
trumpet mouth, having all the lines of reflection convex. The upper part is
open for the passage of the chimney, and upon which the gallery and chimney

page_text: are supported. Above the reflector I place two oil boxes or reservoirs (one on
either side), which reservoirs, on the side or bottom next the reflector, are
convex, to fit as near as possible the concave of the upper side of the reflector,
but at the same time to leave a space between the two for the passage of air.
I prefer to form the sides of the oil reservoirs in lines radiating from the centro
of the reflector or burner, as it exposes less surface to receive heat from the
lamp.
The heat of reflector acting on the air in the spaces between it and the oil
reservoirs produces rarefaction of the air, and having free entrance at the
lower part, and free escape at the top, a continual circulation of air takes
place through those passages, which prevents. the oil becoming too heated."
The burner is supported in the centre of the reflector by two arms, one from
either reservoir; these are very narrow, to obstruct as little light and throw
as little shadow as possible, but are enlarged by angular pieces at the junction
with the burner, in order to contain a considerable supply of oil at that point..
The burner used is the argand or circular wick burner, which is placed on
a wire wick holder, and can be removed or replaced thereon when required.
The lower part of the lamp is enclosed by a glass dish or plate, and for
railway carriages is fitted into an external case, supported in and fitted to the
hole in the carriage roof in the ordinary manner. The gallery resting on the
top of the reflector clasps and holds the chimney or glass in a vertical position,
and supports a lower gallery in which the chimney, rests, and which can be
elevated or depressed from above by suitable nuts and screws connected with
the upper gallery or glass holder.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexis Jean Dessales in the Great Seal Patent Office on
the 25th July 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXIS
JEAN DESSALES, of 13, Rue des Enfants Rouges, Paris, in the Empire of
France, and of 43, Southampton Buildings, Chancery Lane, in the County
of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of January, 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 me,
the said Alexis Jean Dessales, Her special licence that I, the said Alexis

page_text: Jean Dessales, my executors, administrators, and assigns, or such other's as
I, the said Alexis Jean Dessales, 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 "IM-
PROVEMENTS IN OIL LAMPS, AND IN REFLECTORS FOR THE SAME, FOR RAILWAY
CARRIAGES, AND OTHER PURPOSES," upon the condition (amongst others) that I,
the said Alexis Jean Dessales, my executors or administrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexis Jean Dessales, do hereby declare
the nature. of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the fol-
lowing statement, reference being had to the Sheet of Drawings hereunto
annexed, and to the letters and figures marked thereon (that is to say):-
My improvements in oil lamps, and their reflectors, refer principally to lamps
for lighting railway and other carriages from the roof, but also applicable to
similar lighting purposes, such as the cabins of ships, where the lamp is inserted
through the deck, and the light required to be generally diffused.
I form the reflectors circular, with a reflecting surface somewhat like a
trumpet mouth, having all the lines of reflection convex.
The upper part
is open for the passage of the chimney, and upon which the gallery and
chimney are supported. Above the reflector I place two oil boxes or reser-
voirs, one on either side, which reservoirs, on the side or bottom next the
reflector, are convex, to fit as near as possible the concave of the upper side
of the reflector, but at the same time to leave a space between the two for
the passage of air, or air spaces may be formed for this purpose. Although
not subject to much change of air, but are simply open at top, I prefer to
form the sides of the oil reservoirs in lines radiating from the centre of the
reflector or burner, as it exposes less surface to receive heat from the lamp.
Instead of making two reservoirs in this way, the oil box may extend all
round, as will herein-after appear.
The heat of the reflector acting on the air in the spaces between it and the
oil reservoirs produces rarification of the air, and having free entrance at the
lower part, and free escape at the top, a continual circulation of air takes

page_text: place through those passages, which prevents the oil becoming too hot. The
burner is supported in the centre of the reflector by two arms, one from either
reservoir; these are very narrow, to obstruct as little light, and throw as little
shadow as possible, but are enlarged by angular pieces at the junction with
the burner, in order to contain a considerable supply of oil at that point. The 5
burner used is the argand or circular wick burner, which is placed on a wire
or perforated metal wick holder, on which it can be removed or replaced at
pleasure. The lower part of the lamp is enclosed by a glass dish or plate,
and for railway carriages is fitted into an external case, supported in and fitted
to the hole in the carriage roof in the ordinary manner. The gallery rests on 1
the top of the reflector, and holds the chimney or glass in a vertical position.
It supports a lower gallery on which the chinney rests, while projections,
elevated above the top of the reflector, steady the glass chimney.
DESCRIPTION OF DRAWINGS.
Fig. 1 represents a transverse vertical section of a lamp, with reflector and i
lanthern, constructed according to my Invention, fitted and adapted to the roof
of a railway carriage; Fig. 3 is an external view of the saine, while Fig. 2
represents a sectional plan of the lamp and reflector on the line A, B, Fig. 1.
In this lamp the oil box a, a, is represented as being carried all round the
reflector; b, b, is the reflector, which it will be seen in the section, Fig. 1, is
convex, and so as to distribute the rays of light much more than is effected by
a conical, or parabolic, or other concave reflector, or of any reflector curved
in the opposite direction. This curve may be modified to suit the size of the
compartment of the railway carriage or other space to be lighted, as exemplified
in Fig. 8. In this Figure the extreme outer or red lines a, a, show the ordinary
conical reflector, while the lines 1, 2, 3, and 4 represent such as I adopt,
according to circumstances, and the extent over which the light is to be diffused:
The oil box a, a, is fitted between an outer casing or frame c of the lamp and
an inner plate e, following somewhat the convex from of the reflector. dis
the air space between c and reflector b, which, in the example, Fig. 1, has no
air thoroughfare, but is furnished with perforations at top to permit the ingress
and egress of air. The space between c and e receives the oil box, and the
lower part forms a receptacle for the oil as it escapes from the box a by the
passage f, which is fitted with a valve g, as usual in fountain lamps. The oil
box is filled at the aperture f, and then inverted, the valve preventing the
escape of oil. When it is placed in position, the valve spindle comes in
contact with the bottom, and opens the valve. h is the gallery, with pendent
pieces i, i, to carry the chimney, and raised arms k, k, to steady the glass at

page_text: the upper part; is a glass dish, either ground or clear, through which the
light passes; and by which the whole is enclosed from below. This glass is
received in and rests on the lip of the metal casing m of the lantern; this
metal casing is of a double thickness, the inner one being thickly studded with
small perforations, and the outer one with larger holes near the bottom only,
but which do not coincide with any of the smaller holes, whereby the indraught
to the lamp is equalized; air also enters at the bottom between the two thick-
nesses of metal. The lower part of the reflector has small feet, which rest on
the glass dish ; and keep it raised therefrom, so as to permit the free ingress
(all round) of air to the burner.
The case of the lantern is furnished with a rest p, which rests on the roof
of the carriage and has a cover or top constructed to facilitate free egress of
the products of combustion at the top; this top is hinged at q, and has a spring
catch at r, whereby it opens for placing or removing the lamp. The lower part
of this cover consists of three thicknesses, the first or outer ones of which is
close except near the top and bottom; the second t is close except at top; the
inner one wis studded with perforations. v, v, is a perforated cover imme-
diately over the chimney. The arrows show the direction of the currents.
Between the outer and middle casing both hot and cold air enters, as seen;
the hot air passes from inside of lamp to produce an upward draught, and a.
greater proportion of cold air from without to keep the exterior of the
lamp cool, while at the same time the heat and products of combustion pass
through and v, the whole passing upwards into the cap, and out at w.
Fig. 4 represents a plan, Fig. 5 a side view, Fig. 6 and 7, horizontal
sections, of the wick holder. It consist of an outer cylinder of woven wire or
perforated metal, on which the cylindrical wick is placed. The bands or hoops
3. y, fixed inside the outer cylinder z, fit the burner of the lamp, and always
keeps it steady, and at the same time affords a clear space for the supply of oil
inside the wick. The oil having free access to the inside of cylinder, passes
through that cylinder to the wick; this wick holder may be removed and
replaced at pleasure, for the purpose of supplying or removing the wick when
the lamp is trimmed, which, however, requires no attention when the lamp is
burning. The supply of oil to the burner passes by the two arms 5, 5, from
the oil boxes, which arms also carry the burner. Air enters the interior of
the burner and on the exterior, whereby the flame is well supplied, and produces
perfect combustion.
Fig. 9 represents a section of another lamp, showing the air thoroughfare
d, d, between the reflector b, b, and the oil boxes. The heat of the reflectors
and interior of the lamp causes rarification, and consequently air is drawn in

page_text: at the lower part 6, 6, where it has perforations open to the perforations of
the outer casing, and a free escape being provided at 7, 7, a constant change
of air takes place in-space d, d, thereby keeping the oil box a, a cool. The
other parts of this lamp are nearly similar to Fig. 1, and therefore need not be
again described.
Fig. 10 represents another lamp, in plan, which is furnished with two oil boxes
a, a, according to my Invention; they are fitted into receptacles for receiving
the oil, and are in every respect precisely similar in cross section to Fig. 9,
from which it will be readily understood, the only difference in the lamp being
that there are two oil boxes instead of one all round; each box is fitted with
an escape valve g, such as appears on the right-hand side of Figs. 1 and 9.
These lanips may be otherwise fitted to lanterns or covers according to the
purpose required, or they may be suspended by chains or otherwise from the
ceilings of ships' cabins and other compartments, for which the light may be
suitable.
Having described the nature of my Invention, and the manner in which
it is performed, I would have it understood that what I claim, and desire to
protect by the before in part recited Letters Patent, is,―
*First, forming the reflectors of the lamps herein-before described convex,
to produce a better diffusion of the light, as herein-before described.
Secondly, I claim the use and application of the air space and thorough-
fare d, d, for keeping the air cool, and also fitting and placing. the oil box
or boxes of such lamps in the position and in the manner herein-before
described.
Thirdly, I claim the arrangement and construction of the wick holder, as
herein-before described.
In witness whereof, I, the said Alexis Jean Dessales, have hereunto set
my hand and seal, this Twenty-fifth day of July, in the year of our
Lord One thousand eight hundred and fifty-six.
Witness.
W. CLARK, Patent Agent,
53, Chancery Lane, London.
A. J. DESSALES. (L.S.)
.