IMPROVEMENTS IN RAILWAY LAMPS
Year: 1863

page_text: LETTERS PATENT to Joseph Pope Culverwell, of the City of Dublin,
Gentleman, for the Invention of "IMPROVEMENTS IN RAILWAY LAMPS."
Sealed the 7th January 1864, and dated the 31st July 1863.
PROVISIONAL SPECIFICATION left by the said Joseph Pope Culverwell at
the Office of the Commissioners of Patents, with his Petition, on the
31st July 1863.
I, JOSEPII POPE CULVERWELL, of the City of Dublin, Gentleman, do bereby
declare the nature of the said Invention for "IMPROVEMENTS IN RAILWAY
LAMPS," to be as follows:-
My Invention has reference to railway lamps for burning volatile oils, and
consists of the improvements herein-after explained, by which improvements
volatile oils may be conveniently and economically burned in railway lamps.
In order to check the rapid flow of air through the lamp case, which occurs
when the lamp is in rapid motion on a railway train, and which interferes with
the proper burning of the volatile oils, I employ a check plate in the chimney
of the lamp case, the said check plate consisting of a disk of metal placed in
the said chimney. The said disk is perforated with a series of small holes,
through which small holes the heated air and products of combustion pass
from the lamp, the flame is thereby made clear and steady, and is not liable
to be put out in an exposed situation during the rapid motion of the train.

page_text: I prefer to employ a glass chimney around the flame much shorter in length
and larger in diameter in the part immediately surrounding the flame than
chimneys of the ordinary kind.
In order to keep the reservoir containing the volatile oil cool, and thereby
prevent the volatilization of the said oil by the heat of the lamp, I isolate the
lamp case from the reservoir, and thus prevent tho conduction of heat from
the said case to the reservoir. The lamp case and reservoir are so arranged
that a current of air can pass over the top of the reservoir, and the said reservoir
is thereby more effectually preserved from the effect of the heat of the lamp.
The burner of the lamp is also isolated from the reservoir, and provision madg
for the current of air on the top of the reservoir by connecting the lamp case
to the reservoir by means of two strips of wood on two opposite sides of the
bottom of the lamp case, the two intermediate sides being unprovided with
strips of wood, there are left open spaces on those sides equal in thickness to
the said pieces of wood, and through the said spaces air enters and passes over
the top of the reservoir. The burner is isolated from the reservoir by a ring
or support of wood,
In order to prevent any vapour which may be formed in the reservoir
from escaping at the wick, and thereby producing a jumping motion in the
flame, I make a small opening in the top of the reservoir for the escape of the
vapour, which opening I make to communicate with the chimney of the
lamp, or the atmosphere where convenient, instead of with the interior of the
lamp case.
In order to prevent the running down of the rack by which the wick is
raised and supported, and which frequently happens by the shaking of the
carriage, I pass a pin through the base of the burner, which pin passing
through the wick prevents its descent. The same result may be attained by
means of a spring tongue cut in one side of the wick holder, which said spring
tongue permits of the rising motion of the wick for trimming, but prevents
the descent of the wick by the shaking motion of the railway carriage.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Pope Culverwell in the Great Seal Patent Offico
on the 23rd January 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
POPE CULVERWELL, of the City of Dublin, Gentleman, send greeting.
WHEREAS 1ler most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of July, in the year of our Lord One

page_text: thousand eight hundred and sixty-three, in the twenty-seventh year of Iler
reign, did, for Herself, Her beirs and successors, give and grant unto me, the
said Joseph Pope Culverwell, Her special licence that I, the said Joseph
Pope Culverwell, my executors, administrators, and assigns, or such others
as I, the said Joseph Pope Culverwell, 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 Inven-
tion for "IMPROVEMENTS IN RAILWAY LAMPS," upon the condition (amongst
others) that I, the said Joseph Pope Culverwell, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describo 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 J, the said Joseph Pope Culverwell, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
My Invention has reference to railway lamps for burning volatile oils, and
consists of the improvements herein-after explained, by which improvements
volatile oils may be conveniently and economically burned in railway lamps.
In order to check the rapid flow of air through the lamp case, which occurs
when the lamp is in rapid motion on a railway train, and which interferes with
the proper burning of the volatile oils, I employ a check plate in the chimney
of the lamp case, the said check plate consisting of a disk of metal placed in
the said chimney. The said disk is perforated with a series of small holes,
through which small holes the heated air and products of combustion pass
from the lamp; or the check plate may bo unperforated, and the heated air and
products of combustion pass around the edge of the said plate, the flame is
thereby made clear and steady, and is not liable to be put out in an exposed
situation during the rapid motion of the train.
In order to keep the reservoir containing the volatile oil cool, and thereby
prevent the volatilization of the said oil by the heat of the lamp, I isolate the
lamp case from the reservoir, and thus prevent the conduction of heat from the
said case to the reservoir. The lamp case and reservoir are so arranged that
a current of air can pass over the top of the reservoir, and the said reservoir
is thereby more effectually preserved from the effect of the heat of the lamp.

page_text: Provision is made for the current of air on the top of the reservoir by con-
necting the lamp case to the reservoir by means of two strips of wood on two
opposite sides of the bottom of the lamp case, the two intermediate sides being
unprovided with strips of wood, there are left open spaces on those sides equal
in thickness to the said pieces of wood, and through the said spaces air enters
and passes over the top of the reservoir.
In order to prevent any vapour which may be formed in the reservoir from
escaping at the wick, and thereby producing a jumping motion in the flame, I
make a small opening in the top of the reservoir for the escape of the vapour,
which opening 1 make to communicate with the metal chimney of the lamp,
or the atmosphere where convenient, instead of with the interior of the lamp
case. I supply air to the interior of the lamp case for the purpose of sup
porting the combustion of the flame of the lamp by means of vertical tubes,
their upper ends opening outside the top of the lamp case, and their lower ends
nearly touching the bottom of the inside of the lamp case, by this means
copious currents of air are supplied to the interior of the lamp case without
affecting the steadiness of the flame.
In order to prevent the running down of the rack by which the wick is
raised and supported, and which frequently happens by the shaking of the
train, I pass a pin through the base of the burner, which pin passing through
the wick prevents its descent. The same result may be attained by means of
a spring tongue cut in one side of the wick holder, which said spring tongue
permits of the rising motion of the wick for trimming, but prevents the descent
of the wick by the shaking motion of the railway carriage.
Having explained the nature of my Invention, I will proceed to describe,
with reference to the accompanying Drawing, the manner in which the same
is to be performed.
Figure 1 represents in vertical section a railway lamp of the kind commonly
called a head or tail lamp for burning volatile oil, in which my several improve-
ments are combined; Figure 2 is a horizontal section of the same taken
through the dotted line 1, Figure 1; and Figure 3 is a horizontal section of
the same taken through the dotted line 2, Figure 1. The same letters of
reference indicate the same parts in Figures 1, 2, and 3.
a, a, is the chimney of the lanp supported by the feet bon the top of the
lamp case c in the ordinary way. To the inner tube a² of the chimney a a
check plate d, consisting of a disk of metal, is connected by the arms or pieces
d, d. The said check plate d has the convex figure represented in the
Drawing. The said check plate may be perforated if necessary, but I have
found that an unperforated check plate, as represented in the Drawing, answers

page_text: is
satisfactorily. The other parts of chimney are of the ordinary construction. The
heated air and products of combustion from the lamp burner e in escaping by
the chimney a strike against the said plate d, and a rapid flow of air through
the lamp case is thereby prevented; by this arrangement the flame of the
lamp is made clear and steady, and is not liable to be put out in,
an exposed
situation during the rapid motion of the train. The burner e which I employ
is of the ordinary construction. 9 is the reservoir containing the volatile oil
for supplying the burner e formed in the hollow base of the lamp case c. The
said reservoir 9 is connected to the lamp case by the screws and nuts at h.
Between the said reservoir 9 and bottom of the lamp case c are two strips of
wood or other imperfect conductor of heat i, i, situated on opposite sides of
the said lamp case c, the two intermediate sides being unprovided with strips
of wood or other imperfect conductor of heat, there are thus left oper
spaces k, k, between the top of the reservoir and bottom of the lamp caso
equal in thickness to the said strips i, i, through which spaces air enters and
passes over the top of the volatile oil reservoir g. The said oil reservoir
thus isolated from the lamp case by the said strips i, i, the said strips pre-
venting the conduction of heat from the bottom of the lamp case to the said
reservoir, the said reservoir being also kept cool by the currents of air
passing over the top of the said reservoir, the said reservoir is thus effectually
preserved from the effect of the heat of the lamp, and the volatilization of the
oil in the said reservoir prevented. The burner e is supported on the top of
the metal tube connected to the reservoir g, and is isolated from the said
tube by a ring or tube of wood or other imperfect conductor of heat m (see
Figure 1) placed between the lower part of the burner e and the tube l. The
part of the burner which rests upon the top of the tube / has a layer of cork
between it and the said tube 2. In the top of the reservoir g an opening is
made, into which opening a short tube n is fixed, one end of the said tube
opening into the reservoir g, and the other end into the interior of the lamp
case c. Any vapour which may be formed in the reservoir 9 escapes by the
said tube n. The tube 2, instead of opening into the interior of the lamp
case c, as represented in the Drawing, inay communicate with the chimney a,
or directly with the atmosphere. By the escape of vapour from the reservoir
by the tube n, instead of at the wick, a jumping motion of the flame is pre-
vented. In front of the interior of the lamp case c are two vertical tubes o, p,
the upper ends of which open outside the lamp case to the atmosphere. The
lower ends of the said tubes open into the interior of the lamp case near the
bottom of the said case, as seen in Figure 1. Air for supporting the com-
bustion of the flame of the lamp passes by the said tubes o, p, to the interior

page_text: of the lamp without affecting the steadiness of the flame. I do not limit myself
to the positions of the tubes o, p, in the lamp case, as they may be placed in
other parts of the case, and more than two tubes may be used. The wick of
the burner e may be prevented from running down by means of a pin passed
through the wick and the base of the burner, or by a spring tongue in the
wick holder, as herein-before explained. These provisions for preventing the
running down of the wick may be dispensed with if the axis of the rack,
by which the wick is raised, be made to work tight in its bearings. In
making roof lamps, according to my Invention, I prefer to make the reservoir
of earthenware or porcelain, in order the more effectually to prevent the
transmission of heat to the oil in the oil reservoir.
Although I have only described and represented my improvements as applied
principally to a head or tail lamp, yet my improvements may be applied wholly
or in part to various kinds of railway lamps, such as side lights, roof lights,
hand lamps, and other lamps used on railways in which volatile oils are
burned, and in which steadiness of light during the motion of the lamp is
required; but as I believe the nature of my Invention, and tho manner in
which the same is to be performed, will be sufficiently understood by the
description herein-before given, and the accompanying Drawing, I do not
consider it necessary to describe or to represent my said Invention in its
application to other kinds of railway lamps.
Having now described the nature of my Invention, and the manner in which
the same is to be performed, I wish it to be understood that I do not limit
myself to the precise details berein-before described and represented, as the
same may be varied without departing from the nature of my Invention; but
I claim as my Invention of improvements in railway lamps, the said improve-
ments having for their object to render railway lamps suitable for burning
volatile oils, and producing a steady flame during the motion of the lamps,-
Firstly, the check plate in the chimneys of the said lamps for the purpose of
preventing a too rapid current of air through the cases of the said lamps, 3
herein-before described and illustrated in the accompanying Drawing.
Secondly, isolating the reservoir containing the volatile oil from the lamp
case, so as thereby to keep the said reservoir cool, and to prevent the volatili-
zation of the said oil, substantially in the manner herein-before described and
illustrated in the accompanying Drawing.
Thirdly, an oscape pipe for any vapour which may be formed in the upper
part of the oil reservoir, as herein-before described and illustrated in the
accompanying Drawing.
Fourthly, introducing air into the lamp case by means of vertical tubes,
3

page_text: substantially as herein-before described and illustrated in the accompanying
Drawing.
Lastly, preventing the accidental running down of the wicks of the lamps
by a pin passed through the said wicks, or by a spring tongue, as herein-before
described.
In witness whereof, I, the said Joseph Pope Culverwell, have here-
unto set my hand and seal, this Nineteenth day of January, in the
year of our Lord One thousand eight hundred and sixty-four.
Witness,
W. THOMPSON,
2, Burnett Place,
Drumcondra Rd.
Dublin.
J. P. CULVERWELL. (L.S.)