IMPROVEMENTS IN THE CONSTRUCTION OF LAMPS
Year: 1877

page_text: LETTERS PATENT to Francis Edward Merry, of Gatliff Buildings, Commercial
Road, Pimlico, in the County of Middlesex, Foreman, for the Invention of
IMPROVEMENTS IN THE CONSTRUCTION OF LAMPS."
"6
PROVISIONAL SPECIFICATION left by the said Francis Edward Merry at the
Office of the Commissioners of Patents on the 21st February 1877.
FRANCIS EDWARD MERRY, of Gatliff Buildings, Commercial Road, Pimlico, in
the County of Middlesex, Foreman. IMPROVEMENTS IN THE CONSTRUCTION OF
LAMPS."
This Invention relates chiefly to railway carriage lamps, or that class of lamps
in which a fixed reflector is employed for throwing down the light from above, but
it may be in part applicable to other arrangements of lamps.
The objects of the Invention are, firstly, to simplify the construction of such
lamps; and secondly, to increase their efficiency.
The oil cup and burner I propose to combine in one piece; thus, I extend the
sides of the oil cup upwards to a dome form, and this dome I slot transversely
like the burner of an ordinary paraffine lamp to receive the wick holder. Oil is
supplied to the oil cup by means of branch pipes leading from the air reservoir,
and a similar arrangement of pipes is forwarded for supplying air to the burner.
The wick holder, which is intended to receive a flat wick, is made with flanges at
its ends and at about the level of its upper edge. This holder is dropped into its
place in the burner, and it is supported by the flanges at its ends resting on the
bottom edges or ends of the slot in the dome. I provide no means for adjusting
the wick in its holder, as the dome which extends above it will create so sharp a
draught that the tendency of the wick to char when it has been properly trimmed
will be to a great extent removed.
This arrangement of wick holder provides for the instant removal of the same and
its replacement by another fitted with a fresh wick.
In order to provide for the better ventilation of the lamp I attach to the reflector
externally of the ordinary cylinder which surrounds the chimney ventilating tubes,

page_text: which, communicating with the space below the reflector, will assist in carrying off
the heat generated in the lamp, without inducing a down draught so detrimental to
the steady burning of the lamp.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis Edward Merry in the Great Seal Patent Office on the 21st
August 1877.
FRANCIS EDWARD MERRY, of Gatliff Buildings, Commercial Road, Pimlico, in
the County of Middlesex, Foreman. IMPROVEMENTS IN THE CONSTRUCTION OF
LAMPS."
This Invention relates to railway carriage lamps, or that class of lamps in a fixed
reflector is employed for throwing down the light from above.
The objects of the Invention are, firstly, to simplify the construction of such
lamps; and secondly, to increase their efficiency.
In the accompanying Drawing, Fig. 1 shows my improved lamp in central
sectional elevation; Fig. 2 is a section taken at right angles to Fig. 1, the detachable
case and glass bowl being removed; and Fig. 3 is a sectional plan of the oil cup
and burner.
In these Figures, A is the oil cup and A¹ the burner. These two parts may be
cast in one piece, or they may be constructed separately and secured together as
shown in the Drawing. The part A¹ extends upwards above the oil cup and takes
a dome form. This dome is slotted transversely like the cap of an ordinary
paraffine lamp to receive the wick holder C; D is the reflector to which are secured
the pendent pipes E, E; that convey air to the burner and serve also to support the
burner in position.
Fitted to the central flanged opening of the reflector is the holder for the
chimney F, and concentric therewith is the ordinary cylinder G of the lamp which
is secured to the back of the reflector. Surrounding this cylinder is the annular
oil reservoir H, of such diameter as to allow a free air space between it and the
cylinder G. This reservoir is held in position by means of the tubes I which lead
down from the reservoir to the oil cup A, and entering it preferably at different
levels supply oil thereto. The reservoir H is charged with oil when the lamp is
inverted through an opening on its under side which is closed by a screw plug H¹.
The wick holder C, which is intended to receive a flat wick, is made with flanges
at its ends "(see Fig. 1)," and at about the level of its upper edge. This holder is
dropped into its place in the burner, and it is supported by the flanges at its ends
resting on the bottom edges or ends of the slot in the dome. I may remark that no
provision is made for adjusting the wick in its holder, as the dome which extends
above it will create so sharp a draught that the tendency of the wick to char when
it has been properly trimmed will be to a great extent removed.
This arrangement of wick holder provides for the instant removal of the same
and its replacement by another fitted with a fresh wick.
In order to provide for the better ventilation of the lamp I attach to the reflector
externally of the ordinary cylinder G, which surrounds the chimney ventilating
tubes K, K, which communicating with the space below the reflector will assist in
carrying off the heat generated in the lamp; and to avoid the possibility of a down
draught so detrimental to the steady burning of the lamp, I cause the upper ends
of these tubes K to enter hoods of pierced metal K¹ which are attached to the
ordinary cylinder G.
In addition to the air supply tubes E, E, I provide the burner with supplementary
tubes E¹, which will allow of additional currents of air passing up to the flame and
increase the efficiency of the burner.
I would remark that by this arrangement of lamp not only is the liability of the
wick to char greatly reduced, but as a consequence of the more perfect combustion

page_text: of the oil the illuminating power of the lamp is greatly increased, and owing to the
thorough ventilation of the lamp and the rapid dispersion of the heat as it is
generated, a cheap oil may with safety be burned, thus effecting a considerable
economy.
Having now explained the nature of my Invention and the manner of carrying
the same into effect, I wish it to be understood, that under the above in part recited
Letters Patent I claim,―
First. The combination of oil cup and burner for receiving the pendent wick
holder, as shown, air being supplied to such burner by the tubes E, E¹, as and for
the purpose above explained.
Secondly. The arrangement of ventilating tubes and hoods K, K, for improving
the ventilation of the lamp and providing against down draught.
In witness whereof, I, the said Francis Edward Merry, have hereunto set my
hand and seal, this Sixteenth day of August, in the year of our Lord One
thousand eight hundred and seventy-seven.
F. E. MERRY. (L.S.)