AN IMPROVE- MENT OR IMPROVEMENTS UPON LAMPS
Year: 1827

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
SMETHURST, of New Bond Street, in the County of Middlesex, Lamp Manu-
facturer, send greeting.
WHEREAS His present Majesty King George the Fourth, by His Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, the Sixth day of November now last
past, did give and grant unto me, the said James Smethurst, His especial
licence, full power, sole privilege and authority that I, the said James
Smethurst, my executors, administrators, and assigns, or such others as I,
the said James Smethurst, my executors, administrators, or assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, an Invention communicated to me by a certain
foreigner residing abroad out of His Majesty's Dominions, of "AN IMPROVE-
MENT OR IMPROVEMENTS UPON LAMPS," in which said Letters Patent there is
contained a proviso, obliging me, the said James Smethurst, by an instrument
in writing under my hand and seal, particularly to describe and ascertain
the nature of the said Invention, and in what manner the same is to be
performed, and to cause the same to be inrolled in His said Majesty's High
Court of Chancery within two calendar months next and immediately after the
date of the said recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully appear.

page_text: NOW KNOW YE, that in compliance with the said proviso 1, the said
James Smethurst, do hereby declare that the nature of the said Invention,
and the manner in which the same is to be performed, are particularly
described and ascertained in and by the Drawing hereunto annexed, and
the following description thereof, that is to say
=
In the Drawing, Figure 1 is a section of one of my improved lamps, which
is constructed upon the hydrostatic principle, the oil being forced up from a
reservoir A in the base of the lamp by the pressure of a heavier fluid through
the pipe or tube B to the burner C of the lamp. The fluid is contained in an
upper reservoir D, from the lower part of which it descends by the pipe E down
to the recess F, formed below the general bottom of the reservoir A, and passing
through an orifice G, presses or forces up the oil, as above described, to the
burning height H, H, as indicated by the dotted line. In order to constantly
preserve or retain the surface of the oil at the burning height, the fountain
principle is adopted in the following manner:-I, I, is an air tube, fitted by
a cone J at its upper part into a conical neck K, aflixed into the top of the
reservoir D. As the oil consumes, the air enters through the small tube I,
and escaping in bubbles through the fluid allows it to descend, and keep up
the oil to its proper height, the level being preserved constant from the bottom
of the air pipe I; as, however, it is necessary for the oil in its turn to raise
the fluid again from below in refilling the lamp with oil, so the funnel L is
provided, which is elevated to such a degree above the top of the burner as
that upon removing the air pipe I and hanging it, by means of a side pin M
forined upon it on the top of the conical neck K, and thus opening a free
passage for the air to enter and escape at the mouth of the neck K, the oil
on being poured into the funnel L, until it will remain stationary at the top
of the neck of the funnel at N, will have raised or forced up the fluid to its
proper height O, in its receptacle D, by reason of its elevation in the funnel L;
and which elevation must be proportional to the height which the fluid is
required to be raised above the level of the bottom of the air pipe I, the
funnel being required to be as much higher as the oil is lighter than the fluid.
In the present example the ratio is as three to two, the fluid being one-third
heavier than the oil, and the elevation correspondent thereto, although any
other convenient ratio may be adopted according to circumstances. In the
side of the conical neck K a slit P is made, shewn in Figure 2, to admit
the pin M, shewn separately in Figure 3, into it on replacing the conical plug
J, and closing the orifice K at the top of the reservoir D, and which must be
done previous to removing the funnel L from the burner C, or otherwise the
whole of the oil would flow over the mouth of the burner into the receiving

page_text: cup; the funnel L is made to fit oil tight upon the outside of the burner C,
by means of several rings or collars of leather, or other fit and proper elastic
substance, firmly secured in the lower end of the funnel; and it is also pro-
vided with a flat circular plate of metal Q, shewn separately in Figure 4, by
dotted lines in Figure 1, and in section at Figure 12, which is supported upon
several arms or bars of metal affixed to the funnel L, as shewn in Figure 4,
so as to afford a space around the plate Q for the oil to pass. The plate Q
is covered with a circular disk of leather or other proper elastic material, held
upon or against its under side by means of a screw; this leather, &c. fits upon
the central air tube R of the burner, and closes it completely when the funnel
is pressed down upon it; the oil is now free to enter the circular space usually
occupied by the wick. The wick, the wick-holder and its tube (when these
are removed) in order to descend and fill the lamp, and this effect is promoted
by the form given to the outside of the burner, which closes at its top as
near to the wick as usual, but is considerably enlarged within below its
top, and thus affords a better passage for the oil than in the ordinary
lamps, whilst at the same time its tapering and rounded top presents a
facility for the fitting on of the funnel. The enlarged space around the wick
also contains such a body of oil, that it always remains cool enough to pre-
vent it from being injured by the heat, and forming a crust upon the wick
of the lamp, as in ordinary lamps. When the funnel remains full of oil,
as before described, before entirely removing it, a slight circular movement
should be given to it, by which the disk of leather, &c. Q may be raised a
little above the mouth of the central air tube R of the burner, and thus allow
part of the oil contained in the funnel above the burner to flow through
it into a receiver S prepared for it on the top of the vessel D, and thus to
remove any portions of wick, &c. from the inside of that air tube; the funnel
may then be entirely removed, it is better, however, previously to allow it to
drip for a while into or over the burner. This overflow of oil is conveyed
through a tube or pipe T, communicating with the receiver S, into a moveable
vessel U placed within the lower part of the outer case of the lamp, and
having a gap or cavity V made in it, as shewn in Figure 5, to permit it to pass
by the tubes or pipes Band E, above mentioned, and from which said moveable
vessel U it may be poured out into the trimming pot; the vessel U is then
again to be replaced. This vessel U must be made large enough to contain
the whole quantity of oil which the lamp holds. In order to afford a passage
to the air through the central air tube R of the burner, it is supported above
the top of the receiver S, upon a semicircular tube W, shewn in the plan,
Figure 6, and which semicircular tube communicates with the oil tube B above

page_text: mentioned.
A spiral groove is formed around the air tube of the burner in
the usual manner, and as shewn in Figure 7, upon which the wick-holder,
Figure 8, also fits as usual; and it may either have jags formed upon its out-
side to hold the cotton wick in the ordinary mauner, or else three spring clips
X, X, X, as shewn in Figures 8 and 9, may be substituted in place of the
jags, and which, when it is pushed down into its place within another tube,
Figure 10, closes upon and keeps the wick firm whilst winding up or down
the spiral groove by turning the glass holder, and on its being raised out of
the tube they spring open and allow the last remains of the wick to be readily
removed. In Figure 1 the body or outer cover of the lamp is shewn as made
in the form of a cylindrical column in a ring, on the upper end of which, shewn
separately in Figure 11, a notch or gap Y is made, which allows a pin Z,
affixed to the upper reservoir D, shewn in Figures 1 and 12, to enter, and upon
turning the cover round a little either way the pin projects over or above
the ring, and holds the cover down upon the base A of the lamp firmly.
A circular ring a, a, formed upon the top of the base, serving to keep
the cover central, as well as to retain the vessel U in its place, and also
to prevent any oil which may have fallen within the ring a, a, from escaping.
And in order to prevent the oxidation or corrosion of the metallic parts
of the lamp, a small plate of zinc b, Figure 1, is soldered to the bottom
of the recess F. Figure 12 is a cross view of the lamp, shewn in section
in Figure 1, with its cover or outer case removed. The same letters of
reference indicating the similar parts in both these and the other Figures.
In case of varying the kind of oil used in these lamps, as, for instance, whether
animal or vegetable oil be employed, the length of the air tube I will
require to be changed accordingly. This may be effected in various ways, for
instance, the tube I may be enlarged sufficiently to receive another tube c, c,
Figure 13, within it, and which may either slide up and down, or be regulated
by a screw at its upper end fitting into a female screw formed within the outer
tube I, and if the screw may not be thought sufficiently air tight, the lower end
of the inner tube c may be wrapped around with woollen or other yarn, thus
forming a kind of piston, and as shewn in Figure 13, or else it may slide
through collars of leather or other proper material, and as shewn in Figure 14,
and in order to prevent capillary attraction the lower end of the internal tube
may be widened in the manner shewn in Figures 13 and 14. When it is
wished at any time to thoroughly cleanse the internal parts of the lamp, after
having filled it with oil and removed the funnel, it is only necessary to take
out the conical plug J, and nearly the whole of the oil will instantly and
rapidly flow out over the mouth of the burner into the receiver, and thence

page_text: into the cup U;, carrying with it any of the remains of wick, sediment, &c.,
which ordinarily clog and injure the burning of other lamps. This lamp,
Figure 1, is to be fitted up with a glass-holder and chimney, and also with
a globe or other formed ground glass disperser and softener of the light
as usual. It has likewise a moveable metal neck d, d, fitted upon its top
around the burner, similar to that upon Figure 15, which is another form of
lamp possessing similar properties with that already described, but in which
the lower part only of the case or outward cover of the lamp e is made
moveable or capable of being lifted up, as shewn by the dotted lines in
Figure 16, in order to put in or remove the receiving cup U, shewn separately
in Figures 17 and 18. The form of the neck d, d, will be understood from
Figure 19, which is a section of it, and in which will be seen a number of
holes f, f, which are made around it to admit the air to pass to the central air
tube of the burner. The upper vessel D, of Figures 15 and 16, is formed in
the body of the lamp itself. The descending and ascending tubes B and E,
and the middle tube T being contained in the body, as shewn by the dotted
lines in Figure 16, and indicated by the letters of reference. A large hole g,
Figure 15, is also provided in the neck d, d, to admit of its passing over the
neck K. Figure 20 is a plan of the base of the lamp, shewn in Figures 15
and 16, taken at the dotted line h, h, in Figure 16, B and E indicating the
two tubes. Figure 21 is a view of the internal parts of the lamp seen from
below, i, i, in Figure 16, chiefly to shew the tubes B, E, and T; the two armis
or braces j,j, which serve to steady the tubes B and E, and the contrivance to
secure the moveable case e firmly to the base A. of the lamp; this is effected
in the following manner-In Figure 16, k, is a gap or notch made in the
periphery of the lamp i, i, as shewn in Figure 16 and 21. In Figure 22, 1, 1,
is a wire or rib affixed within the case e, but not reaching up to its top whilst
this wire or rib is turned out of the direction of the gap k, and in the larger
gap or notch m, Figures 16 and 21, it lodges underneath the upper part of
the latter notch m, and prevents the case from rising. But upon bringing the
wire or rib into the direction which places it under the gap k, the case e may
be raised, as shewn by the dotted lines in Figure 16. n, n, in Figures 16
and 22, is an internal ring which stops against the under side of i, i, as
shewn in Figure 16 by dotted lines, and prevents the case e from being
raised higher than necessary to put in and remove the receiving cup U.
Figure 23 is the glass chimney and globe-holder, shewn separately; Figure 24
is a metal bottle, intended to contain a proper quantity of fluid for each lamp;
Figure 25 is a modification of the lamps before described, with a view to
rendering them, more economical. Here the receiving cup U employed in the

page_text: two lamps described is omitted, and consequently the moveable outer case or
cover likewise; the tube E is likewise formed of the stem or pillar of the lamp
itself, the tube B being contained within it. The base of the lamp resembles
that shewn in Figure 1, and the upper part of the tube B is made rounding,
in order to receive the neck of the funnel, Figure 26, and its collars of leather
upon it, as shewn in the latter Figure; I likewise substitute burners of various
forms, instead of the Argand burners used in the before-mentioned lamps, and
therefore omit the flat plate and leathers described in the funnel, Figures 1
and 12, which were employed to close the central air tubes of the Argand
lamps. 1, however, here provide a side pipe o, in order to allow the excess of
oil to flow off into a vessel placed to receive it, such as the trimming pot, &c.,
when a plug or stopper is removed from the end of the pipe o, I still retain
the air or fountain tube I, as in the former lamps described. 1 can either
employ a round wick or cotton p in this lamp, held in a wick-holder g, as
usual, and as shewn separately in Figure 27, and in its place in Figure 25,
and also in the Plan, Figure 28; or else a flat wick, as shewn in the Plan,
Figure 29, at v, and sideways in Figure 30, and also endways in Figure 31.
As it may be convenient to possess the means of applying different kinds of
burners to one and the same body of my new hydrostatic lamps, so I have
contrived various methods of effecting this object. One of these is shewn in
Figure 32, where the Argand burner c is connected with the top of the upper
reservoir D, by means of the well-known contrivance called by the name of
the union-joint, and which is shewn at s, a wire t being introduced into the
conical plug, and affixed across it, the ends of which project on each side and
fit into two gaps made upon the top of the conical tube to receive them; the
object of this contrivance being to retain the burner in its proper position, and
prevent it from turning round. Another mode is shewn in Figure 33, where
the Argand burner c is united to the upper receptacle, part of which is shewn
at D, by means of a feniale screw, which fits upon a screw made on a stop-
cock u, which is necessary to be used in order to stop the flow. of the oil during
the period of changing the burners, as also to extinguish the lamp on shutting
the cock, a collar of leather being also employed to render the screwed joint
oil tight as usual. Instead of a single Argand or other burner, I can adapt, by
either of the two contrivances above mentioned, or by any other fit or proper
mode of connection, two or more burners at pleasure. Figure 34 represents
two branched Argand burners united to the upper reservoir D, by means of a
stop-cock u. Figure 35 shews a branched piece intended to be screwed upon the
stop-cock, and having at the extremities of the branched tubes reservoirs v, v,
which may hold either flat or round waxed wicks at pleasure, and the centres

page_text: of which reservoirs may either be open to admit air to the flames or be closed.
Figure 36 is a ring reservoir made to screw upon the stop-cock, as shewn
in the section, Figure 37, and having one or more tubes proceeding from its
centre to supply the ring with oil; the form of this ring reservoir is shewn in
the section across it at Figure 88, (which is drawn upon a larger scale), and it
may receive within it circular rings holding any required number of round
wicks, as shewn in Figure 36, or of flat ones, as shewn in Figure 39. It will
also be necessary to employ a funnel capable of being screwed upon the stop-
cock u, similar to that shewn in Figure 40, in order to fill the lamp with oil;
I can also fill the lamp with oil without the use of a funnel, by allowing the
aqueous fluid to flow off as the oil is poured in at the top of the burner
through a side pipe w, shewn in Figure 41, into any proper vessel capable of
containing it. When the oil is poured in, the pipe w must be closed by a
screwed plug a, and the stop-cock u be shut, the aqueous fluid may then be
replaced in the lamp through the neck M, the conical plug J of the air or foun-
tain tube must then be fitted into its place, and the lamp will be ready to light.
The adjusting air and fountain tubes I and c, c, shewn in Figures 13 and 14,
besides accommodating the lamps to the different weights of the oils to be used,
as above mentioned, also possess the property of regulating their height in the
burners to the greatest nicety, and likewise of restoring their height when
nearly consumed, as otherwise there would be a difference in their height equal
to half the depth of the lower receptacle A. I can unite any of the different
kinds of burners with the body of this lamp by a screwed joint without a stop-
cock, and as shewn in Figure 42, which is thus adapted to receive a burner,
similar to that shewn in Figure 83; in this case, however, the air hole in the
conical plug J must be stopped up by a plug, as shewn at y in Figure 42,
during the period of removing or changing the burner, after which it must be
again opened.
I do not mean or intend hereby to claim as parts of this said Invention any
of the contrivances described, which are already known or in use; but I do
hereby claim the application of the fountain principle to an hydrostatic lamp,
by which the height of the aqueous fluid is rendered constant, the use of a
properly contrived funnel or funnels for raising up the said fluid or fluids into
the upper reservoir on pouring in the oil, the method of permitting the aqueous
fluid to run off whilst pouring in the oil at the top of the burner with or
without an ordinary funnel, and of then replacing the said aqueous fluid,
the contrivance for allowing the overplus of oil on removing the newly
invented funnels from the top of the burners to flow into a loose receiving
cup placed in the lower part of the basis of the lamp, and of occasionally

page_text: causing the whole of the oil contained in the lamp to flow out at the
top of the burner by taking out the conical plug J, and thus entirely clearing
the lamp from all impediments arising from portions of the snuffed-wicks,
thickened oil, &c., which might otherwise clog it up; the adjustments' of the
air tube of the fountain by which the height of the oil may be at any time
restored or regulated to the greatest certainty; the modification of the principles
of this fountain hydrostatic lamp to the construction of:lamps for domestic and
other purposes, and with or without solid, round, or flat wicks, the manner of
adopting different burners, whether single, compound, or branched, to the
bodies of the fountain hydrostatic lamps, and the facilities afforded for changing
any of them for others at pleasure.
In witness whereof, I, the said James Smethurst, have hereunto set my
hand and seal, this Fifth day of January, in the year of our Lord One
14 hundred and twenty night.