IMPROVEMENTS IN RAILWAY CARRIAGE LAMPS AND OTHER LAMPS
Year: 1870

page_text: LETTERS PATENT to Eli Henry Griffiths, of Balsall Heath, in the
County of Worcester, Manager of Works, for the Invention of
"IMPROVEMENTS IN RAILWAY CARRIAGE LAMPS AND OTHER LAMPS."
Sealed the 12th May 1871, and dated the 24th November 1870.

page_text: volatile oils in the said lamps, and to obviate the unsteadiness of the
flame which in ordinary lamps. is produced by currents. of air.
In constructing a railway carriage roof lamp according to my
Invention, I suspend the oil reservoir, the wick burner, and parts con-
nected therewith, in the ordinary cup-shaped glass bottom of the lamp,
the said reservoir and parts being suspended by arms from a ring or belt
sliding in the metal body of the lamp, and resting on a shoulder in the
said body. Between the said ring or belt and the body of the lamp
there is a narrow annular space through which air descends to support
combustion. Within the said ring or belt is a reflector, the said reflector
being surmounted by a chimney. Connected to the lower edge of the
said reflector is a lamp glass having the figure of an inverted cone,
the opening at the bottom of the said glass being of slightly larger
diameter than the dome or cone of the burner. The said lower
opening in the glass when the said glass is in its place, is supported
a short distance below the top of the cone of the burner, and permits
a current of air to pass between it and the said dome to the exterior
of the flame. The reflector does not fit closely in the ring or belt
described, a narrow annular space between them permitting of the
circulation of air.
In applying my Invention to signal lamps, I arrange the parts as
follows: The oil reservoir carrying the burner and parts connected
therewith is situated below the body of the lamp being connected
therewith by a hinge joint. The bottom of the lamp case is conical or
pyramidal, the cone or dome of the bottom projecting through an
opening in the said cone or dome. Immediately over the flame is a
reflector having the figure of an inverted conc or pyramid to a
central opening in which a chimney is affixed. On either side the
glass front of the lamp is a vertical plate or division which form
with portions of the cylindrical side of the lamp vertical chambers.
These chambers open at bottom immediately above the top of the
reservoir and at top into the upper part of the lamp into which the
chimney opens. Air is admitted to the lamp through a series of
perforations immediately above the top of the reservoir and below
the conical or pyramidal bottom of the lamp case. When the said
lamp is exposed to currents of air the air after passing in at the
openings described has such free means of egress through the vertical

page_text: chambers. described that the supply of air to the flame is but little or
not at all disturbed. By the arrangements described the flame burns
steadily when the lamp is exposed to currents of air or is moved about
rapidly.
My Invention is applicable to. all lamps in, which. volatile oils are or
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Eli Henry Griffiths in the Great Seal Patent
Office on the 20th May 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ELI
HENRY GRIFFITHS, of Balsall Heath, in the County of Worcester,
Manager of Works, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of November, in the
year of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,.
give and grant unto me, the said Eli Henry Griffiths, Her special licence
that I, the said Eli Henry Griffiths, my exccutors,, administrators, and
assigns, or such others as I, the said Eli Henry Griffiths, 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 "IMPROVEMENTS IN
RAILWAY CARRIAGE LAMPS AND OTHER LAMPS," upon the condition (amongst
others) that I, the said Eli Henry Griffiths, my executors or adminis-
trators, by an instrument 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 per-
formed, 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 I, the said Eli Henry Griffiths, do hereby.
declare the nature of the said Invention, and in what manner the same

page_text: is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
My Invention consists of the improvements herein-after described in
railway carriage lamps and other lamps, my said improvements having
for their object to secure the efficient burning of petroleum or other
volatile oils in the said lamps, and to obviate the unsteadiness of the
flame, which in ordinary lamps is produced by currents of air.
In constructing a railway carriage roof lamp according to my Inven-
tion I suspend the oil reservoir, the wick burner, and parts connected
therewith in the ordinary cup-shaped glass bottom of the lamp, the
said reservoir and parts being suspended by arms from a ring or belt
sliding in the metal body of the lamp and resting on a shoulder in the
said body. Between the said ring or belt and the body of the lamp there
is a narrow annular space, through which air descends to support com-
bustion. Within the said ring or belt is a reflector, the said reflector
being surmounted by a chimney. Connected to the lower edge of the
said reflector is a lamp glass having the figure of an inverted cone, the
opening at the bottom of the said glass being of slightly larger diameter
than the dome or cone of the burner. The said lower opening in the
glass, when the said glass is in its place, is supported a short distance a
below the top of the cone of the burner and permits a current of
air to pass between it and the said dome to the exterior of the
flame. The reflector does not fit closely in the ring or belt described,
a narrow annular space between them permitting of the circulation
of air.
In applying my Invention to signal lamps I arrange the parts as
follows: The oil reservoir carrying the burner and parts connected
therewith is situated below the body of the lamp, being connected there-
with by a hinge joint. The bottom of the lamp case. is conical or
pyramidal, the cone or dome of the burner projecting through an a
opening in the said bottom of the lamp. Immediately over the flame
is a reflector having the figure of an inverted conc or pyramid to a
central opening, in which a chimney is affixed. On either side the glass
front of the lamp is a vertical plate or division which form with portions
of the cylindrical side of the lamp vertical chambers. These chambers 3
open at bottom immediately above the top of the reservoir, and at
top into the upper part of the lamp, into which the chimney opens.

page_text: Air is admitted to the lamp through a series of perforations above the
top of the reservoir and below the conical or pyramidal bottom of the
lamp case. When the said lamp is exposed to currents of air the air.
after passing in at the openings described has such free means of egress
through the vertical chambers described, that the supply of air to the
flame is but little or not at all disturbed.
By the arrangements described the flame burns steadily when the
lamp is exposed to currents of air or is moved about rapidly.
My Invention is applicable to all lamps in which volatile oils are or
may be burned.
Having explained the nature of my Invention I will proceed to
describe with reference to the accompanying Drawings the manner in
which the same is to be performed.
Figure 1 represents partly in vertical section and partly in elevation
a railway carriage roof lamp constructed according to my Invention;
Figure 2 represents in elevation the oil reservoir, wick burner, and parts.
connected therewith, detached from the case of the lamp; Figure 3.
represents in clevation, Figure 4 in vertical section, and Figure 5 in.
plan, the reflector,. lamp glass, and chimney detached. The same letters
indicate the same parts in Figures 1, 2, 3, 4, and 5.
a is the ordinary cylindrical case or body of the lamp provided with the
cup-shaped glass bottom b; c is the ordinary jointed cover or top of the
lamp case. Suspended in the case or body a of the lamp is a metallic
ring or belt d to which the oil reservoir e is connected by the arms f,f,
The said metallic ring or belt d is capable of sliding into or out of the
metal body or case a of the lamp. On the outer side of the ring or
belt d are ribs d, &, which ribs when the ring or belt, d is placed in the
body or case a rest upon the shoulder a² at the junction of the body a
with the glass bottom b, and thereby suspend the said ring or belt
and parts carried by it in the body or case a. The vapour of petroleum
escapes from the reservoir e by the arms f,, which are tubular, the said
tubular arms being connected to the tubular ribs &, d. Between the
ring or belt d and the body a of the lamp a narrow annular space is left
down which the air passes to support combustion; g is the wick burner
of the lamp of the ordinary kind used in lamps for burning petroleum
or other volatile oils; is the moveable cone of the burner. Within
the ring or belt d is a reflector i, the said reflector being surmounted by
.

page_text: a chimney k. Around the chimney is a perforated tube 7, between which
tube and the chimney air circulates, and the said chimney is thereby
kept cool. Connected to the lower edge of the reflector i is a lamp
glass m of the figure of an inverted conc. The bottom of the lamp
glass m is supported upon the projections h² of the cone 7, so that the
lower edge of the said glass is situated a short distance below the top of
the cone of the burner. The diameter of the opening in the bottom of
the lamp glass m is greater than that of the cone h, the space thus left
between the glass and cone permits a current of air to pass to the
exterior of the flame. The reflector i and parts carried by it are sup-
ported upon the cone of the lamp burner by the lamp glass m resting
on the said cone, and the said reflector is firmly secured within the ring
or belt d by the spring arms bearing upon the inside of the said belt.
The reflector i does not fit closely in the ring or- belt d a narrow space
between them permitting of the circulation of air. The conical lamp
glass m is secured to the lower edge of the reflector i by the hook-
shaped clamps p. These clamps slide radially on the upper side of the
reflector i, and are fixed by the binding screws q. By releasing the
clamps p and sliding them outwards, the lamp glass m may be removed
for cleaning. When the lamp glass is removed access to the reflector i
for cleaning is obtained. The whole of the lamp being carried by the
ring or belt d the removal of the said ring or belt detaches the whole of
the parts from the body or case a of the lamp, as represented in Figure 2.
The lamp glass m, reflector i, and chimney 7, are also capable of being
separated from the ring or belt d by lifting them out of the said ring or
belt as illustrated in Figures 3, 4, and 5. When the ring or belt d and
the several parts of the lamp are suspended in the lamp body or case a,
as illustrated in Figure 1 air enters the body or case a, in the ordinary
way and passing down the annular spaces between the ring or belt d
and body or case a and between the said ring or belt, and the reflector i
enters the burner through the ordinary perforations at g³, and passes to
the exterior of the flame by the openings between the exterior of the
cone h, and the bottom of the lamp glass m.
Lamps of the kind described may be used for ship's cabins, and for

page_text: oil is supplied to the lamp, and the said lamp is unaffected by the currents
of air to which it is exposed in use.
Figure 6 represents in side elevation a signal lamp constructed and
arranged according to my Invention; Figure 7 represents the same open;
Figures 8 and 9 represent vertical sections of the same taken at right
angles to one another; Figure 10 represents a horizontal section of the
same taken on the line x; Figure 8 and Figure 11 is a plan of the
under side of the body or case of the lamp. The same letters indicate
the same parts in Figures 6, 7, 8, 9, 10, and 11.
a is the case or body of the lamp; 6 is the oil reservoir carrying the
burner c and other parts of the lamp. The said oil reservoir 6 is situated
below the body a of the lamp, and is connected therewith by the hinge
joint d; e is the spring fastening for fixing the reservoir to the body of
the lamp; fis the bottom of the lamp case. The said bottom is conical
h
or pyramidal, the cone of the burner c projecting through an opening f*
in the said bottom f; g is the reflector over the flame, the said reflector
having the figure of an inverted cone or pyramid, a chimney / being
affixed to a central opening in the reflector g. The lower part of the
body of the lamp is divided into three parts or chambers k, l, m, by the
vertical V shaped plates or divisions n, n, and side plates p, p. In the
central part or chamber m of the lamp the flame from the burner c is
situated, the heated air and products of combustion from which rise up the
said central chamber m, and pass by the chimney h to the upper part
of the lamp case or body from whence they escape by the perforated
jointed cap or cover q. The outer chambers k, l, form exit passages
for the air supplied to the lamp case, the said chambers opening at top
into the case or body above the reflector g. The exposed sides of the
V shaped divisions n as well as the upper side of the bottom ƒ of the
body are reflecting surfaces. Air for supporting the combustion of the
flame enters the lamp immediately above the reservoir by the per-
forations and below the bottom of the lamp case. When the lamp is
exposed to currents of air, the air passing into the body of the lamp by
the openings at has such free means of egress through the vertical
chambers k, l, that the supply of air to the flame is but little or not at
all disturbed. Air is also admitted to the lamp by perforations at 's in
the sides of the case. The air entering the lamp by the perforated sides
does not pass directly into the vertical chambers k, l, in consequence of

page_text: the plates p dividing the said chambers from the case of the lamp. The
vapour from the petroleum in the reservoir 6 escapes from the said
reservoir by the pipes t, t, the said pipes opening into the vertical
chambers k, l.
The jointing of the reservoir to the lamp case in the manner described
greatly facilitates access to the reservoir and to the wick burner.
Instead of using two vertical chambers in the case of the lamp for
facilitating the escape of the air entering the said case, one vertical
chamber only may be employed, and the shape of the said chamber or
chambers may be varied.
In large lamps, the lamp proper, that is, the jointed reservoir, burner,
and case, in which the air exit chamber or chambers are formed, and
the chimney may be made separable from the outer case or body of the
lamp, so as to be made capable of being placed in and removed from
the outer case or body of the lamp. This form of my Invention is
particularly useful for ship's side lamps and masthead lamps, but may
also be applied to other 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 herein described and illustrated,
as the same may be varied without departing from the nature of my
Invention, but I claim as my Invention,―
Firstly. The improvements in railway carriage and other roof lamps,
and other lamps herein-before described and illustrated in Figures 1, 2,
3, 4, and 5, of the accompanying Drawings, that is to say, suspending
the reservoir containing the volatile oil in the metal body or case of tlie
lamp by means of a metal ring or belt capable of sliding into and out
of the lamp case, and combining with the said ring or belt a detach-
able lamp glass reflector and chimney, constructed and arranged
substantially as described and illustrated.
Secondly. The improvements in signal, ship, and other lamps herein-
before described and illustrated in Figures 6 to 11 (both inclusive) of
the accompanying Drawings, that is to say, jointing the reservoir
containing the volatile oil and carrying the lamp burner to the bottom
of the lamp case and constructing the lamp case with a vertical chamber
or chambers for giving free egress to the air entering the lamp, whether

page_text: the jointed reservoir and the air exit chamber or chambers be combined
with the outer case or body of the lamp, or with a separate case, which
can at pleasure be introduced into or removed from the outer case or
body substantially as described and illustrated.
In witness whereof, I, the said Eli Henry Griffiths, have hereunto
set my hand and seal, this Seventeenth day of May, in the year
of our Lord One thousand eight hundred and seventy-one.
ELI HENRY GRIFFITHS. (L.8.)
Witness,
HENRY SKERRETT,
Clerk to George Shaw,
Birmingham.