CERTAIN IMPROVEMENTS APPLICABLE TO LAMPS AND REFLECTORS
Year: 1802

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
SMETHURST, of Saint Margaret's Hill, Southwark, in the County of Surrey,
Lamp Manufacturer and Contractor, and NICHOLAS PAUL, of Villiers Street. in
the Strand, in the County of Middlesex, Mechanician, jointly and severally,
send greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Thirtieth day of
October, in the forty-third year of His reign, did give and grant to us, the
said James Smethurst and Nicholas Paul, our executors, administrators, and
assigns, His said Majesty's special licence that we, the said James Smethurst
and Nicholas Paul, our executors. administrators, or assigns, during the term
of years therein expressed, should and lawfully might use, exercise, and vend,
within that part of the United Kingdom of Great Britain and Ireland called
England, the Dominion of Wales, and Town of Berwick-upon-Tweed, and
also in His Majesty's Colonies and Plantations abroad, our Invention of
"CERTAIN IMPROVEMENTS APPLICABLE TO LAMPS AND REFLECTORS;" in which said
Letters Patent there is contained a proviso obliging us, the said James
Smethurst and Nicholas Paul, or one of us, particularly to describe and
ascertain the nature of the said Invention, and in what manner the same is to
be performed, by an instrument in writing under our hands and seals, or the
hand and seal of one of us, and cause the same to be inrolled in His Majesty's
High Court of Chancery within six calendar months next and immediately

page_text: after the date of the said Letters Patent, as in and by the said Letters
Patent, relation being thereunto had, may and will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, we, the said
James Smethurst and Nicholas Paul, do hereby declare that our said Inven-
tion, and the said improvements applicable to lamp and reflectors, consist in
several particulars with respect to each, the most important of which may be
classed under two general heads. to wit, improvements applicable to the
lamps themselves, and improvements applicable to reflectors.
The improvements applicable to the lamps themselves are,--
Firstly, that by means of a drawing or register tube, with a proper register
adapted to it, in the lower part of the case or receptacle in which the lamps
are contained, of air tubes in or out of the body of the lamp itself, of a proper
sloping form given to the superior part or shoulder of the lamp near the
burner, and of a proper form given to the glass chimney or dome of the lamp
surrounding the burner (all of which will be hereafter more particularly
described), or such of the said contrivances as are applicable in any particular
case, that degree of access of air to the burning portion of the wick which is
capable of producing the most accurate and luminous combustion of the oil,
grease, tallow, wax, or other oleaginous, sebaceous, or combustible substance,
with which the lamp is supplied, may be constantly maintained and supported,
and the flame at the same time rendered as long as is consistent with such
accurate and luminous combustion, so that the greatest possible efflux of light
which a wick of any given form and dimensions, supplied with any given
oleaginous, sebaceous, or combustible substance, is capable of affording, may be
constantly produced.
Secondly, that by means of a simple contrivance (also to be herein-after
more particularly described). the burner containing the wick may be easily
removed from the lanp, either for the purpose of cleaning it, or for substi-
tuting in it's stead another of different form or dimensions. And,
Thirdly, that by means of certain other simple contrivances (also to be
herein-after more particularly described). a more copious and unimpeded flux
of the oil, grease, tallow, wax, or other oleaginous. sebaceous, or combustible
substance, with which the lanip is supplied, may be afforded to the wick.
The improvements applicable to the reflectors are,-
Firstly, that they shall be so formed as to reflect those rays issuing from the
frame of the lamp, which, without their interposition. would fall in a direction
in which they would be useless, according to the purpose for which the lamp
is applied, in such a manner as to diffuse and distribute them over the whole

page_text: surface or extent of space to be illuminated. so that the whole of the light
falling on every portion of such surface or extent of space, both from the direct
rays of the lamp and after reflection from the reflector, may be as nearly equal
and uniform as is practicable. And,
Secondly, that the reflector shall be so constructed as to reflect such rays as
fall on those paris of it which are nearest to the flame of the lamp to the
most distant parts of the surface or extent of space to be illuminated, and such
of the rays as fall on those parts of the reflector which are most distant from
the fame of the lamp to the nearest parts of such surface or extent of space
to be illuminated, so that with respect to every part of the reflector the
reflected ray may be the longer in proportion as the incident ray is the shorter,
and the converse.
Having thus stated in general terms the principle objects of our improvo-
ments, we shall proceed to explain them more in detail with reference to the
annexed Drawings. In the annexed Drawing, No. I.. Fig. 1, represents the
common street lamp with its reflectors, according to our present mode of con-
structing it, inclosed in it's glass vase J. with it's rim K. and cover N; and
Fig. 2 the same lamp, with its reflectors viewed at right angles to their posi-
tion in Fig. 1, and taken without the glass vase J or its cover N; the several
other Figures from 3 to 14, in the same Drawing, representing the various
parts as taken separately. The same letters of reference denote the same
parts, both in those Figures in which they are taken separately, and in the
Figures 1 and 2, in which they are represented together. A. Fig. 1, 2, and 3.
is the body of the lamp, through the bottom of which pass the two air tubes a, a,
open at the top and bottom, and passing in the present instance through the
oil when the lamp is filled. This, however, is not absolutely necessary, as they
may, by changing the form of the body, also be made to pass on it's outside.
The slope b, d, represents the form of the superior part of the lamp, and
which is materially conducive to the brilliancy of it's flame by preventing
that impediment to the current of air on the outside which would be pro-
duced by a larger surface at b, b, with a square shoulder. It contains the
wick-holder B, Fig. 4 and 5, which is a flat tube or pipe, having the metal of
which is formed prolonged below on one side in a curved direction, nearly to
the bottom of the body of the lamp, in order to support the wick and to assist
the oil or other combustible material employed in it's ascent. This tube is
fixed into a convex circular plate, which rests upon three or more projecting
parts made on the inside of the conical part of the body of the lamp at b, b,
for the purpose of supporting it, and whose use is to cover and defend the oil
or other combustible material employed from dirt, and from the action of the

page_text: flame of the lamp, and it has two slits or holes made in it (as represented in
Fig. 6 and 9) to permit the air pipes a, a, in the body of the lamp to pass
through. When grease, tallow, wax, spermaceti, or any other fit combustible
material to be consumed, which requires to be kept in a state of fusion, an
additional tube is fixed underneath it to permit a piece of metal wire P
(Fig. 2) to be put through it, which reaches to the bottom of the body of the
lamp, and whose upper extremity rises above and is placed so near the end of
the flame of the lamp as to be heated by it sufficiently to warm the bottom of
the body of the lamp, and by this means to keep the combustible material
employed in a fluid state and fit for combustion. When oil is employed it is
kept in a due temperature by the vicinity of the flame alone, without the
necessity of employing the said wire P to heat it. The body of the lamp d
is contained in the exterior case or receptacle C (Fig. 2 and 7), from the
bottom of which a tube proceeds, the intention of which is to cause a proper
draught of air to the bottom of the lamp. To the bottom of this tube a
moveable cup c is fitted, having its sides perforated with a number of holes or
slits, so that by sliding this cup upwards or downwards it performs the office of
a register or regulator, and the quantity of fresh air necessary to be admitted
through the said drawing or register tube C and the air pipe a, a, so as to sup-
port the combustion. The combustible material employed is admitted and
regulated, and passing through the said air pipes a, a, in the body of the lamp
A, is directed upon each sides of the flame in currents, so as to act upon it
with that degree of force which is found by experiment to be most conducive
to the brilliancy of the flame. The upper part of the said tube proceeds a little
above the exterior case or receptacle C, in order to catch and detain any small
portion of oil or other combustible material employed which might happen to drop
upon the said bottom, and thereby prevent its falling into the said tube. Upon
the flat upper part of the body of the lamp A are fixed three or more thin and
narrow plates of metal which are shewn at d, d, d, (Fig. 9,) the use of which
is to support the glass dome or chimney. D (Fig. 8) so as to permit a third
current of air to pass underneath it, and by the sloping or conical sides b, d,
b, d, (Fig. 3) of the superior part of the body of the lamp, which third current
causes the wick of the lamp to burn much longer without requiring to be
snuffed, and tends to keep up a proper degree of temperature in the atmo-
sphere immediately surrounding the flame, and to maintain a due supply of
air in a fit state for supporting combustion to every part of the flame. O
(Fig. 1, 2, and 10) is a metal ring having two recesses made in it to permit
two projecting parts e; e, fixed to the receptacle of the lamp C (Fig. 1, 2, and
7) to pass through them, which projecting parts when entered being turned

page_text: round towards the right hand until they are in contact with the stops f. f.
made on the upper part of the ring E; the said receptacle C. containing the
body of the lamp A, in its proper position in the said ring. The body
of the lamp A has a projecting piece e. (Fig. 1. 2. and 3.) which fits into
a recess made for it in the side of the receptacle C, by means of which the
body of the lamp is kept in a proper position in the receptacle C. and thus the
flame becomes properly posited in respect to the reflectors hereafter to be
described. The stops f,, (Fig. 10) also prevent the receptacle C from being
turned the wrong way on entering it into the ring E, and determine the proper
situation of the two supports e. e. when the receptacle is to be taken out of the
said ring. Two arms g, g. Fig. 1, (one of which is also exhibited in Fig. 2.)
project on each side from the recesses in this ring E, having slits to receive the
ends of the decending branches or legs p, p, of the metal chimney F. and
which said ends are rivetted or otherwise fixed to the ring E at g, g, and
thus connect the lamp A, in its receptacle C. with the said metal chimney F.
In this chimney are made two slits i. i. (Fig. 1, 2, and 11.) the use of which is
to receive the two arms of a thin metal fork G, which passes through them
into the interior of the said metal chimney F. and thereby supports the glass
dome or chimney D. by the selvage or rim at it's upper extremity (as shewn
in Fig. 8 and 12) in the metal chimney F. when the lamp A and its recep-
tacle C are withdrawn. The fork G is retained in its place in the metal
chimney F by means of the pin H, (Fig. 1, 2, and 18.) which is put through
holes made in the upper part of one of the branches h. and through the fork
itself. When the glass chimney D is required to be removed it may of course
be done by taking out the pin H. and the fork G, and may be again restored
to its place in the metal chimney F by a contrary operation. To the upper
part of the metal chimney F are fixed two hooks j. j. (Fig. 2) the lower parts
of which are bent at right angles, and have each an hole in them r, r, the use
of which will be explained hereafter. By these hooks j. j. the whole lamp
and its reflectors (whose form and construction are more particularly
described hereafter) are suspended to the cross bar I, which has the part
represented between the said hooks i, i, curved sideways, as well
prevent it's hindering the free escape of the heated air from the lamp
as to determine the exact position in which the said hooks j.. j, must be
placed on the said bar 1. so that the lamp may be suspended in the middle
of the glass vase J. The ends of the cross bar I are bent downwards at
right angles, and fit to loops k, k, made in the metal rim K, which sup-
ports the glass vase J, and which is thereby kept in a proper position. From
the lower part of the metal chimney F two hooks (Fig. 2). project, which pass
through two holes d, d, in the wing reflectors L, L, and thereby support the
to.

page_text: extremities of the said reflectors which are nearest to the metal chimney F,
leaving the opposite extremities of the said reflectors at liberty to be elevated
or depressed as occasion may require. A circular portion of each of the said
wing reflectors is cut away at the extremities nearest to the said metal
chimney F, so as to admit it to pass through and suffer these extremities of
the said wing reflectors to come as nearly as possible in contact with each
other, so that as many as possible of the rays of light proceeding upwards from
the flame of the lamp A may be intercepted and reflected by the said wing
reflectors L. L Projecting rims or ledges are also formed in these parts of
the metal chimney F for the wing reflectors to rest upon. The said wing
reflectors L, L, have also fixed to each of them a hook M. M, (Fig. 1. 2, and
14,) having a joint at n, n, and a female screw at o, o. into which screw the
hooks p, p, with the lock hars q, q. and these screwed hooks p, p, being put
into the holes r, r, in the hooks j. j, before mentioned, compleat. the supports
or suspensions of the wing reflectors L, L, which by aneans of the said screwed
hooks p, p, may be raised or lowered at their extremities, which are the
farthest from the metal chimney F, and so as to direct the reflected rays of
light proceeding from them either more horizontally or upwards or downwards
as may be required. When the wing reflectors are brought into the required
positions they may be retained there by means of lock bars q, q, being brought
into contact with the jointed hooks M, M, at o, o, (Fig. 2). The glass vase J
is fitted with its cover N in the usual manner, and is held in the iron ring of
the lamp iron by means of three or more metal straps soldered to the ring K.
two of which are shewn at 8, 8. (Fig. 1). In the lower part of the vase J is
an aperture large enough to permit a man's hand to pass through, to put in
or take out the lamp A in its receptacle C. The vase has a metal rim O
cemented to it, round which pass two projecting ledges to hold the moveable
metal ring t, t; to this ring t, t, is attached a hinge u, of a plate of metal, or
in its stead a ring fitted with a piece of glass, which serves to close the said
aperture, and is capable of being turned round to any position at pleasure, that
when hanging down it may screen the lamp from the wind whilst it is lighted.
When shut up it is retained in it's place by the spring t, and it has a ring at
16, by which it may be pulled open.
We have been thus minute in our description of the preceding lamp not
because all the minute circumstances of its construction as we have described
it are equally applicable to lamps intended for every purpose, but for the pur-
pose of conveying such an idea of the objects to which our improvements are
directed, and the mode in which they are effected, as may put the public in the
fullest possession of our Invention, and enable them to derive every possible
advantage from it when the term of our said Patent shall be expired.

page_text: The annexed Drawing, No. 11., represents a lamp for lighting rooms, halls,
or other places where its light is wanted to be equally diffused or distributed
all around it in a nearly horizontal direction, and which therefore, instead of
what we have called the wing reflectors belonging to the street lamps, has a
circular one. The general construction of this lamp is very analogous to that
of the one described in the Drawing No. 1., and the same letters of reference
likewise apply to this; we shall therefore only have to point out the different
forms of some of it's parts. For instance. the body of the lamp A has no
projecting piece as at E (see the Drawing No. 1.), nor is there any recess made
to receive it in the receptacle C and E for the purpose of fixing the exact
position of the flame, it being quite indifferent which way it is situated in
regard to the circular reflector. The receptacle may have a vase or other shape
given to it, and there are several holes made in the extremities of the branches
p, p, descending from the metal chimney F (instead of one only as in Drawing
No. 1.) in order to afford an opportunity of raising or lowering the ring E,
containing the lamp A in its receptacle C. and by this means placing the same
nearer to or farther off from the circular reflector Q, and in consequence
thereof causing the reflected rays of light to be spread to a greater or lesser
extent round and underneath the lamp at pleasure; and when the desired
situation is found it may be fixed there by means of the two pins being put
through the said holes and other holes made in the two arms of the suspending
ring E at g. g. (Fig. 1). The lower part of the metal chimney F is also made
of a different form, not being shaped like that shewn in the Drawing No. 1..
but cylindrical, with a ledge or rim projecting outwardly all round it for the
circular reflector Q to rest upon. The places of the two metal hooks 1. j. are
also changed in order to suffer the said circular reflector to pass over them by
means of the two recesses made in each side of the circular holes in the center
of the said circular reflector to permit the shoulders of the metal branches
h. h. to pass through them, and thereby causing it to rest upon and he supported
by the said ledge or projecting rim at the lower part of the metal chimney; by
means of the two metal hooks j. j. the whole may be supported underneath a
metal or glass disk, which may prevent the smoke from injuring the ceiling.
The mode of regulating a part of the air to support the combustion of the
material employed is varied in this construction. the cape being made entire,
and the slits or holes for the air to enter at being made at the lower part of
the tube C. This lamp may be suspended and inclosed in a glass vase similar
to that shewn at J. Fig. 1. No. 1.: but when it is intended to be used within
doors. the said glass vase is not necessary to be employed. and more especially
by changing the construction of the air register e to that shown by Fig. 8 and 9

page_text: in this Drawing, we oblige the air to pass into the tube C upwards through
its bottom instead of sideways, and thereby prevent the flame from being
disturbed by any accidental current of wind which might happen to arise. In
order to effect this, to the bottom of the tube C'is fitted a plate of metal having
a hole in its centre, and one, two, three, or more other holes round its circum-
ference, with spaces between them equal to their diameters, and another similar
plate of metal, having like holes and spaces made through it, is placed either
above or below the first-described plate, and by means of an axis which passes
through the said plate, and is fixed to the second plate, and terminates below
in a stud or knob. this last-mentioned plate can be turned round so as to
shut or open the said holes, and thereby suffer more or less air to pass through
them, as may be required.
Fig. 7
In Fig. 2, Q is a plan of the circular reflectors having the two recesses
made on each side the central hole; and in Figs. 3, 4, 5, and 6. Q, Q,
exhibit four different sections through the centres of circular reflectors
intended to shew some of the variations made by us in our reflecting curves,
according to the different purposes they are intended to answer.
represents a table lamp for domestic or other purposes, which likewise
having several of it's parts made similar to those of the lamps last described,
and the same letters of reference applying to thein, it will be needless to do
nore than to point out the variations to fit it for the above purpose, which are as
follows: The receptacle C, containing the body of the lamp A, made similar to
that in Fig. 1 just described, has its tube made longer in order to clevate the
flame above the table. To the lower part of it a foot or pedestal R is attached
in order to enable it to stand upon a table or other proper support; and the
mode of regulating part of the air to effect the combustion of the oil or other
combustible substance employed is by means of a moveable ring S, which is
fitted to the lower part of the tube, having holes with spaces between them
equal to their diameters made in it, and the lower part of the tube having
likewise similar holes and spaces made in it to correspond with those in the
ring, so that, by turning the ring a little one way or the other, more or less
air may be admitted as required, as in the other lamp lastly, described. At T
are shewn two metal branches which are fixed to the circular reflector Q, whose
lower parts being received into two loops made in the receptacle C, support
the said reflector, and this also keeps the glass chimney from falling; but
when the lamp is used without the reflector, the glass chimney must be kept in
its situation by means of the ring connected with a proper branched metal
support shewn by the dotted lines, the two ends of which fit into the said two
loops in the side of the receptacle C. The lower part of the glass dome or

page_text: chimney D is kept in it's situation upon the flat top of the body of the lamp
A by means of three or more metal pins fixed to the said body, two of which
are shewn at d. d, and which apply themselves to the outside of the said glass
dome or chimney D.
In the Drawing No. III., Fig. 1 represents a lamp for lighting halls. passages,
staircases, or other similar purposes, and which is likewise capable of being
used as a bracket or table lamp. It consists of some parts which are common
to the lamp last described and shewn in Fig. 7 of the Drawing No. II.. and
the same letters of reference apply also to it. The variations are as follows:--
The tube C is shortened, and below the moveable ring c of the air register
Sa base or foot W is fixed. having within it an additional tube X. made
somewhat tapering, the use of which is to place the lamp in the socket of a
candlestick. or the catch box of of a glass vase. such as is commonly used for
a passage lamp, in which latter case the circular reflector Q may be also
suspended in the glass vase by means of the chains and hooks Y. Y. Y. and
by means of the circular hole in its centre being made wider, as seen at Z, it
will not so much hinder the light of the lamp from proceeding upwards, and
will still reflect some of the rays underneath the lamp. When the said circular
reflector is intended to be used with a table lamp it may be suspended by
means of branches fixed to it, and also fixed to a socket sliding upon the
supporter of the glass dome or chimney D.
In the Drawing No. IV., Fig. 1 represents a mode of adapting one of the
circular reflectors Q to a common patent lamp, having a circular reservoir for
the oil above. In order to this a hook is fixed to the tube proceeding from
the said reservoir, a recess or slit is made in one side of the reflector to admit
the tube, and close to the said slit is made a hole to permit the said hook to
pass through, by which means the reflector is sustained on that side. On the
other side of the reflector a small plate is fixed, having a hole through it,
and another corresponding hole being made underneath the reservoir, the
reflector is put into it's place by being suspended upon the hook fixed to the
tube from the reservoir on one side, and having a metal pin put through the
hole in it's plate. and in the reservoir on the opposite side, to complete its
suspension.
Fig. 2 of the same Drawing represents our mode of adapting one, two, or
more burners, with either one or two flat wicks in each, or one, two, or more
burners, with circular wicks, to such a vase or other reservoir for oil, A, upon
a stand, as is commonly in use, by means of our screwed conical joints, so that
any of them may be employed at pleasure, and that they may easily be
separated in order to clean them, or for any other purpose. B is a burner

page_text: composed of a metal tube or body to contain the oil, and a wick-holder C,
having two flat wicks c, c. parallel to each other, with an air pipe b placed
hetween them, the lower end of which being open. has a register F to admit
and regulate one part of the air which supports the combustion of the oil
employed. D is a glass dome or chimney on an improved construction, it
having a dome at d. d. and a narrow tube above, and being made longer in
the part below the flame than those hitherto employed. It is fitted into a
proper supporter E, which has a spring tube at e to enable it to be fitted upon
the outside of the body of the burner B, so as to slide up and down, and be
retained in the desired position at pleasure, and it has also a ring or hook
above it to confine the glass chimney and keep it steady. A number of holes
are made through that part of the supporter E on which the glass chimney D
rests, in order to permit. another current of fresh air to pass through them.
which moves with rapidity between the body of the burner B and the elon-
gated part of the glass chimney D. and being reverberated upon the flame by
means of the dome of the chimney at d, d, completes the combustion of the
oil, and the heated and decomposed air escapes with velocity up the narrow
tube of the chimney. A Plan of this part of the supporier, with it's holes, are
also represented separately at E. Fig. 8.
Another improvement in the construction of this lamp consists in removing
the ring or hoop i, j, of the supporter E. The glass chimney D so far below
the flame of the lamp as not to hinder the rays of light thereby produced
from proceeding on all sides. The wick-holder C is supported in the body of
the lamp B upon three or more short pins, as seen at g, g, g. G is a small
glass cup supported in a metal ring to detain any oil which might leak from
the burner B
Fig 3 and 4 represent the double wick-holder of the burner B shewn in
two different positions.
In Fig. 5, H is a lamp composed of a metal tube or body to contain the oil,
and having a wick-holder with one flat wick. The upper part of this tube
is made sloping or tapering on each side at i, i, in order to conduct the fresh
air which passes through the holes in the supporter E of the glass chimney D
just described in Fig. 2, in two currents, one on each side of the flame. The
wick-holder h may be either supported on four short pins withinside the body
of the burner H, two of which arc shewn at g, g, or as shewn in Figs. 6
and 7, which represent the single wick-holder in two different positions, with
hooks i, j, projecting at each end, whereby it may be supported on the top of
the body of the burner H.

page_text: supporter E of the glass chimney D, so as to make it serve as a register for
the admission of fresh air. Instead of holes being made in the part which
supports the glass chimney, it is composed of two metal plates, both of which
have one, two, three, or more similar holes, with spaces between equal to
their diameters; the lower plate being moveable, it can, by means of the
stud p, which projects from it below, be turned more or less, so as to shut
or open the holes, and thereby suffer more or less air to be admitted as may
be found necessary. Instead of using a spring tube, and for fixing the
supporter E of the glass dome or chimney on the burner of the lamp, as in
Fig. 2 and 5, the tube kinay be divided half way round at 1. 1, and again
at m, so as to fit loosely upon the outside of the burner B (Fig. 2).
H (Fig. 5), or 1. (Fig. 9), and the two ends being connected by the screw o, it
may, by tightening this screw, be retained in any situation on the outside of
the said burners.
Fig. 9. I is a semicylindrical section of a burner having a circular wick,
and a contrivance for raising it. The different parts of this burner are shewn
separately by Figs. 10, 11, 12, 13, 14, and 15, and the same letters of refer-
ence apply to them all.
Fig. 10 shews the body of the burner to contain the oil. It consists of two
tubes, the innerinost being fixed to the outermost at it's lower part, and being
open below has an air register F to regulate one part of the air which supports
the combustion of the oil. and a projecting rib 9. 9. fixed to it, the use of
which will be described hereafter. To the lower part of the outer tube is
fixed a short tube a. on the outside of which is a male screw, and the inside of
which is made conical, the use of which will likewise be presently described.
Holes are made through the said outer tube, where the above described short
tube is fixed to it, to admit oil, and keep out any extraneous substance.
Fig. 1 shews that part of the hurner K which serves to raise the wick;
it consists of two tubes fixed to each other at top, and having a space between
them sufficient to permit the outer tube of Fig. 10, 1, to pass between them.
The inner tube has a spiral groove or screw-Nike channel r, r, 7, 7, 7, 7, 7, T, T, F.
made within it.
Fig. 13 and 14 exhibit two different views of the wick-holder; being a short
tube. the upper outside half of which is made of a lesser exterior diameter
than the lower, in order to receive the circular wick of the lamp upon it,
which is confined in it's place by the thin metal ring or ferrule, Fig. 15, being
slipped over it. This wick-holder slides up and down upon the inner tube of
the body of the burner I, Fig. 10. and is prevented, from turning round upon
it by means of a grooves withinside of it, which receives the projecting

page_text: rib,, Fig. 10, before described. The exterior surface of the lower part of
the wick-holder has a number of perpendicular furrows made round it, as
represented in Fig. 13, to permit the oil to pass by it to the wick, and has
besides a short pin or stud fixed to it. which slides in the spiral or screw-like
groove r, r, r, on the inside of the inner tube K, Fig. 11, before described,
so that by means of the said tube being turned either one way or the other
the wick-holder is raised or lowered.
Fig. 12 is a metal ring, which fits on the inside of the top of the tube K,
Fig. 11, and is made conical withinside. It's use is to confine the wick. To
this burner the glass chimney D, and it's supporter E, are adapted in the
same manner as is shewn in Figs. 2 and 5. and the supporter being attached
by means of it's spring or screw tube e or k to the outer tube K, Fig. 11. upon
it's being turned either one way or the other, the said outer tube Kis
consequently turned with it, and thereby raises or lowers the wick of the lamp.
Fig. 16, 17, 18, and 19 represent the parts which form our screwed conical
joint shewn in different positions.
(Fig. 17 and 18) to
outside of the short
Fig. 16 exhibits part of the pipe which proceeds from the reservoir A
(Fig. 2), having the part a of the joint fixed to it. This part a is made conical
at the end on its outside, and so made to fit exactly into the conical part of
the short screwed tube a, fixed to the burners B (Fig. 2). H (Fig. 5), and
1, 1, (Fig. 9 and 10). This pipe (Fig. 16) has besides a projecting shoulder
at , u, for the inner part of the screwed ring a
press against, and this ring being screwed upon the
conical tube a, Fig. 5, 9, and 10, either by means of it's milled edge, or by
means of the claws of the wrench. Fig. 24, being inserted into the two slits or
notches v, v, made in the said milled edge for that purpose until it is tight, it
will bring the conical parts of the joint A into close contact with each other,
and render the joint sufficiently secure.
Fig. 23 exhibits a mode of applying our egg-shaped reflector (which reflects
the light in one direction only, and which is herein-after described) to a lamp
with either one or two flat or circular wicks.
The Drawing No. V. represents a mode of adapting any of our burners, by
means of our screwed conical joint, to a reservoir containing oil placed above
the lamp A, (Fig. 1 represents a burner having two flat wicks, with its air pipe
and register, glass chimney and supporter, already described. It is fixed to the
tube B by means of the said screwed conical joint at a. This tube B slides
upon the inner tube C, which descends from the reservoir of oil D, and is
prevented from falling by means of the notch e made in the metal spring E,
fixed to the said reservoir, catching the metal piece b, having a hole in it

page_text: through which the said spring E passes. This inner tube Chas a conical
valve at c. such as is commonly employed: and the center tube B has a metal
plate perforated with holes fixed at d. which catches the shank or foot of the
said conical valve. and consequently lifts the valve itself. when the tube B
is thrust up into the position represented in the Drawing, and thereby permits
the oil to flow from the said reservoir D to the lamp A. A semicylindrical pipe /,
closed at bottom but open at top. is fixed to the side of the outer tube B. and
communicates with it's inside by an orifice at m. in order to admit air and suffer
the oil to flow. The reservoir D has fitted to it a stopcock F, having a funnel
through which the reservoir may be filled with oil when the valve is closed by
lowering the tube B. and with it the burner A. into the position represented by
the red lines, and the cock must be closed previous to the valve being opened
by the burner A and tube B being thrust up again into their former position.
The reservoir D is supported upon the plate G, which is attached to the metal
chimney H, the upper part of which has two metal hooks g, g. fixed to it.
whereby the whole lamp is suspended from the cross bar 1. Two slits h. h.
onc in each side of the metal chimney H, receives the branches of the metal
fork, which supports the glass chimney of the lamp when the lamp is with-
drawn, and also connects the reservoir D with the said metal chimney. Two
hooks K. K. (Fig. 2) having a hole at the lower extremity of each to receive
the jointed screwed hook of the winged reflectors, are also fixed to the said
metal chimney, when those reflectors are intended to be used with the lump.
as represented at L. (Fig. 1), the said reflectors being supported in the same
manner as is already described in the Drawing No. 1, Fig. 1 and 2; where a
circular reflector is intended to be used it is supported by a circular rim or
ledge round the metal chimney in the manner described in the Drawing
No. 11. Fig. 1. When the lamp is to be lighted the burner is drawn down
into the position represented by the sketch made in red ink, and a second notch
c, in the spring E, then falls into the hole in the plate b, and retains it in that
situation. Upon pressing the spring E towards the tube B it is again dis-
engaged. and the burner may then be moved upwards or downwards as
required.
Fig. 2 in the same Drawing represents the metal chimney H. G is the
plate which supports the reservoir for oit, and is itself supported by means of
the two hooks K. K, K, K. which. proceeding underneath the plate G. rise
again on each side the metal chimney until they terminate in two hooks above
K, K. which fit into two notches made for them in the upper part of the
metal chimney H. by which means the said plate G may be removed when a

page_text: circular reflector is to be employed, and may be reinstated in order to receive
the reservoir D. At h is shewn one of the slits which receive the fork i: and at
11. two hooks, which pass through holes made in the wing reflectors to receive
them, and on which the reflectors rest at their extremities which are nearest
to the metal chimney.
In Fig. 3, D is the reservoir for oil, with it's stopcock F. it's descending inbe
C. and it's valves at c, and the spring E. with it's two notches at e. e.
In Fig. 4, A represents the burner of the lamp with it's two wicks and air
pipe. a is the conical screwed joint by which it is attached to the tube B,
which has a projecting piece b, having a hole in it through which the spring E,
Figs. 1 and 3, passes. a plate perforated with holes at d. to lift up the plug of
the valve c, Figs. I and 3, and a semicylindrical pipe /, closed at the bottom
but open at top, attached to it, and communicating with it's inside by an orifice
at m for the purpose of admitting air, and suffering the oil to rise in the said
semicylindrical pipe or cistern.
Having thus described generally the leading objects of our improvements,
and given the most full and explicit details respecting such of them as relate
to the construction of the lamps themselves, it remains for us to show the
geometrical construction of the forms of the reflectors, so that they may
answer the purpose for which they are intended, to wit, that of so reflecting,
diffusing, and distributing such rays of the lamp as would be otherwise useless,
or as many of them as possible, that the surface or extent of space to be
illuminated may be as uniformly illuminated as may be. The particular mode
of effecting this depending of course on the particular form and dimensions of
every such surface or extent of space to be illuminated, all that can
be done is to lay down as perspicuously as possible the principles on which
the construction of the reflector is performed in all cases. and then give
some examples of the application of these principles in the most ordinary
instances.
Let L, Fig. 1, in the annexed Drawing No. VI., represent the frame of a
lamp; A, B, the extent of the surface or extent of space to be illuminated.
which we are in the present instance supposing to be a horizontal plane; R.
Q. the convenient extent or dimensions of a reflector, which may be applied
to the lamp so as to intercept those rays which would otherwise fall in a
direction in which they would be useless, or as many of them as may be,
R being the nearest and Q the farthest convenient distance of any part
of the reflector from the flame of the lamp L. Now, according to the
principles already laid down, those rays of the lamp fall on R, the nearest

page_text: point of the reflector. are to be directed to B. the most distant point of
the surface or extent of space to be illuminated; and those which fall on Q, the
farthest point of the reflector, are on the other hand to be directed to A. the
nearest point of the surface or extent of space to be illuminated, or directly
under the lamp. Draw therefore 1. R. and L. Q. and R, B. and Q. A.
Now, as the angles of incidence and reflection are equal, it is manifest that if
we draw through R a right line p q. and through Qanother right line a. z.
so that the angle 1. R, p. may be equal to the angle B. R. q. and the angle
T. Q. a, equal to the angle A, Q. z. the said right lines p, q, and a, z. will be
tangents to the course of the reflector at the respective points R. and Q.
Draw therefore the right lines p. q. and a, 2, in this manner accordingly, and
their respective directions coinciding with those of the curve of the reflector
at those points, the latter are consequently given. Now, in order to ascertain
the direction of the curve of the reflector at a convenient number of interme-
diate points (as for instance four), and be thereby enabled to trace the proper
curve through these points, draw as many right lines 1, S, LU, L W, and
LY, so that the angles R. LS, SLU. UL W. WL Y. and YL Q. may
be equal to each other, or so that the whole angle R L Q, may be divided by
the lines LS. LU. L W. and L Y, into equal parts. Divide the right line
A B into equal parts at as many intermediate points between A and B (as in
the present instance four), C. D. E and F. and draw S F. UE, W D, and
YC; draw also the right lines rs, 1, 0, and g., through the respective
points S, U, W and Y, so that the angle LS may be equal to the angle
WL, equal
SF, the angle UL. equal to the angle u li E, the angle
to the angle w W D. and the angle Y L. equal to the angle Y C. and
the respective right lines r s. tu, vw, and r, so drawn, will respectively
coincide with the required curve of the reflector R Q. at those respective
intermediate points S. U. W, and Y. through which the required curve R Q
may be accordingly easily traced by hand. If we are to suppose the whole
surface or extent of space to be illuminated to be circular or equally extended
on every side of the lamp. then it is obvious that the reflector must be of a
figure which would be generated by the revolution of the curve R Q. about
TR, as an axis, as in the case of the circular reflector Q. Fig. 1, in the
annexed Drawing No. IV. If, on the other hand, we are to suppose that the
space to be illuminated is of such a nature that it is only desirable that the
rays should be reflected in the direction or towards the side B of the lamp,
then the proper form of the reflector will be that of a kind of hood or bonnet
formed by the revolution of the curve R Q. about the line L B, as an axis, as

page_text: in Fig. 5 in the Drawing No. III. Having thus formed a pair of solid patterns
or dies of the proper form, to wit, one for the exterior or convex surface, and
the other for the interior or concave surface of the reflector, they are to be
struck off with a proper fly press in such manner as is already frequently used
for reflectors of different forms, and in a great variety of analogous operations,
in which thin plates of metal (as coffin plates) are struck into concave, convex,
or embossed or enchased forms. In the said annexed Drawing No. VI., Q. Q.
Fig. 2 represents a section of such a circular reflector as is already described at.
Fig. 1. No. II., and Fig. 1. No. IV.. and which is here supposed to be applied
to one of Smethurst and White's paient lamps, as in the latter of those two
Figures. In the present Figure the several lines marked a. a. a. &c. represent
the direct rays of the lamp as issuing from the flame A; c. c, c. &c. those rays
of the lamp which are incident on the reflector Q, Q: and d. d, d, &c. the
course or direction of the same rays after reflection. from which it will be
seen that those which are incident on those parts of the reflector which are
nearest to the flame are reflected the greatest distance and vice versa. Q, Q
Fig. 3, in the same Drawing. represents a section of another circular reflector
analogous to the former, but which differs from it in being calculated for the
illumination of a circular space of limited extent, so that the distapce to which
it reflects the most distant rays is also limited, and the degree of illumination
on such limited space consequently increased. In Fig. 4 in the said
Drawing, m, n, m 1 n. m 2 n, m 3 n, represent four sections of reflectors of
different degrees of curvature according to the extent of this limitation.
Q, Q. Fig. 5, in the same Drawing represents a section of a reflector, which
is so constructed as to reflect the rays nearly perpendicularly, but rather in a
converging direction, and which is applicable to such lamps as are intended to
be suspended at the top of a well staircases or in similar places. In this case
on glass dome or chimney is absolutely necessary, but a short metal chimney F
is applied at the top of the reflector, and the whole is suspended by a curved
wire f, f. f. B, Fig. 6, in the same Drawing, represents a convenient form of
a reflector for a carriage lamp, in which the center of the illuminated space is
at an angle of depression of about forty-five degrees from the lamp. It will
appear from what has been before stated that the principles herein-before laid
down, both with regard to the construction of the lamps themselves and with
respect to the forms of the reflectors, are advantageously applicable in an infinite
variety of cases, and we feel it right to say that it is these principles, however
applicable, that we conceive ourselves entitled to the sole and exclusive appli-
cation of for the term mentioned in His Majesty's said Royal Letters Patent,

page_text: force and virtue thereof, and which it is the object of His Majesty's said
oyal Letters Patent to secure and defend.
In witness whereof, we, the said James Smethurst and Nicholas Paul,
have hereunto set our hands and seals, the Thirtieth day of April,
in the forty-third year of the reign of our Sovereign Lord George
the Third, by the grace of God of the United Kingdom of Great
Britain and Ireland King, Defender of the Faith, and in the year
of our Lord One thousand eight hundred and three.
NICULAD
Sealed and delivered (being first duly
stamped) in the presence of
J. FLETCHER.
J. STEEVENS.
AND BE IT REMEMBERED, that on the same Thirtieth day of April,
in the year above mentioned. the aforesaid James Smethurst and Nicholas
Paul came before our Lord the King in His Chancery, and acknowledged
the Specification aforesaid, and all and every thing therein contained, in
form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute in that case made and provided.
alled the same Thirtieth day of April. in the year first above written.