A CERTAIN IMPROVEMENT OR CERTAIN IMPROVE- MENTS IN OR APPLICABLE TO LAMPS
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN'
DAVIS, of Brettell Lane, in the County of Stafford, Glass Manufacturer, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Third day of June, in the eighth year of Her reign, did, for.
Herself, Her heirs and successors, give and grant unto me, the said John Davis,
Her especial licence, full power, sole privilege and authority, that I, the said John.
Davis, my exors, adiñors, and assigns, or such others as I, the said John Davis,
shall at any time agree with, and no others, from time to time and at all times
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, my Invention of "A CERTAIN IMPROVEMENT OR CERTAIN IMPROVE-
MENTS IN OR APPLICABLE TO LAMPS;" in which said Letters Patent is contained
a proviso, that I, the said John Davis, shall cause a particular description
of the nature of my said Invention, and in what manner the same is to be
performed, to be inrolled in Her.said Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had.
doth more:fully and at large appear.
NOW KNOW YE, that in compliance-with the said proviso, I, the said John
Davis, do hereby declare that the nature of my said Invention, and the manner
in which the same is to be performed, are fully described and ascertained in

page_text: and by the following description thereof, reference being had to the Drawing
hereunto annexed, and to the figures and letters marked thereon, that is
to say:-
My Invention consists, firstly, of a method of manufacturing or constructing
the glass shades or chimneys used for lamps in such a manner that a part or
parts of the said shades or chimneys being made opaque or semi-opaque, by the
application of a layer or stratum of enamel, or by painting, or by the process
called silvering, the said opaque or semi-opaque part or parts act as a reflector,
and reflect the light falling thereon, in the manner herein-after explained.
Secondly, of a method of constructing the chimnies of lamps, whereby the
said chimnies may be more readily ornamented than when made according to
the ordinary method of construction; and wherby my improvement of the
introduction of opaque or semi-opaque reflecting parts in the shades of lamps
is more conveniently applied to certain kinds of lamps.
Figures 1, 2, 3, 4, represent my Invention of the introduction of opaque or
semi-opaque reflecting surfaces in the chimnies or shades of lamps, as applied to
shades or chimnics of several kinds of lamps. Figure 1 represents, in elevation,
the shade of a hemisphere or table lamp to which my Invention is applied, and
Figure 2 represents a plan of the same. Figure 3 represents, in elevation, a shade
for a candle lamp to which my Invention is applied; and Figure 4 represents, in
elevation, a shade or "moon" (a as shade of the form represented is commonly
called) for a gas lamp to which my Invention is applied. Those parts of the
shade marked a, a', Figures 1 and 2, are formed of white enamel, or any other
opaque or semi-opaque glass; I prefer, however, white enamel to every other
kind of glass; the part of the shade marked b is made of transparent and
colorless glass. The part a of the shade forms an annular reflector (see
Figure 2), situated very nearly over the flame of the lamp; and it is evident
that the greater part of the light which is radiated by the flame upon the said
reflecting part of the shade will, from the opacity of the enamel and
brillancy of its surface, be reflected downwards, and illuminate the table
or surface on which the lamp stands.
It is obvious that if the enamel is sufficiently thick, it will completely inter-
cept the whole of the light falling on it, and that nearly the whole of the
said light will be reflected; and it is also obvious, that by varying the thickness
or opacity of the said enamel, any required proportion of the light falling
thereon may be reflected downwards, or transmitted through the enamel
upwards. Figure 3 represents the application of my Invention to a shade or
chimney of a candle lamp, the parts marked c, c', being the reflecting parts,
made of opaque or semi-opaque enamel; and the part marked d is made

page_text: of transparent and colorless glass. Figure 4 represents the application of my
Invention to a shade, or chimney, or "moon" of a gas lamp, the part marked
⚫ being the reflecting part, made of opaque or semi-opaque enamel ; the part
marked f is made of transparent and colorless glass. The enamel of which
the said reflecting parts of shades are made, may either be coated on tho
exterior or on the interior surface of the colorless and transparent glass of
which the said shades are made, or the said enamel may be introduced between
two layers or strata of glass. The last method is that which I prefer. The
method of coating one layer of glass upon another is well known, and
commonly practised; I therefore deem it unnecessary to describe the mannor
of manufacturing my said Invention, as the workmen employed in the glass-
manufacture are well acquainted therewith; and the method to be pursued in
manufacturing the said shades or chimnies constitutes no part of my
Invention.
In addition to the methods of carrying out my Invention of the intro-
duction of opaque or semi-opaque reflecting parts in the shades or chimneys
of lamps, herein-before described, and represented in Figures 1, 2, 3, and 4 of
the accompanying Drawing, I sometimes carry my Invention into effect in
a different manner; for example, I sometimes construct shades for lamps
in which the enamel reflecting parts are situated at the lower part of the said
shades and below the flame of the lamp, so as to reflect the light of the
said flame upwards, and I sometimes place the said reflecting parts on the
side of the said shades, so as to reflect the light horizontally. Besides the
method herein-before described of producing a reflecting surface, that is to
say, by the introduction of a stratum or layer of enamel, I sometimes produce
the said reflecting surfaces by coating the exterior surface of those parts of the
lamp which I wish to reflect the light with paint, so as thereby to produce
reflection, and I sometimes also produce the same effect by silvering the said
parts; but I prefer the use of enamel to the use of either paint or silvering, as
the latter, that is to say, paint and silvering, are affected by the heat of the
lamp, and are otherwise liable to be injured and detached from the glass.
Although I have only described my Invention in its application to an oil, a gas,
and a candle lamp, it is obvious that it is equally applicable to every other
kind of lamp, from whatever source the light of the said lamp is obtained; but
as the application of my Invention to the shades or chimneys of other kinds of
lamps does not differ from the methods of applying it herein-before described,
I deem further description unnecessary.
Figure 5 represents my improved method of constructing chimnies for
amps. 9, 9, 91, represents the chimney; and h (in dotted lines) represents the

page_text: shade by which the said chimney is in part surrounded. In the ordinary
method of constructing chimnies and shades, the parts g, h, are made of one
piece, and the chimney g', 9, which by its form determines à more or less
perfect combustion in the flame of the lamp, is altogether detached from the
shade, and is situated in the interior thereof.
My improvement consists in constructing a chimney for a lamp in such a
mauner, that when used with a shade of a spherical or other suitable form the
upper part 9" of the said chimney has the appearance of the upper part of a
shade (see a¹, Figure 1). By this method of construction, the parts g" and h
being separate, they can be more readily ornamented than when they are in
one piece; and in carrying into effect my herein-before described Invention,
that is to say, the introduction of a reflector of opaque or semi-opaque enamel
to the shades of lamps, my improved method of constructing chimnies for lamps
enables me to introduce the said reflectors into those portions only of the said
shades in which a reflecting surface is wanted. For example, in the shade
represented in Figures 1 and 2 it may be desired to limit the reflecting surface
to the annular portion a; but when the whole of the shade is made of one
piece, as represented in Figures 1 and 2, there is much difficulty in introducing
the enamel into the part a without at the same time coating the part a¹ with
the said enamel; but by constructing the shade and chimney in the manner
herein-before described, and represented in Figure 5, the upper portion of the
shade or chimney 91 (see also a', Figure 1,) may be made of colored or
colorless glass, and ornamented in any desired manner. Although in carrying
into effect the last-described Invention, I prefer making the chimney of the
form represented in Figure 5, that is to say, contracted at the parts marked i
and j, I do not limit myself to the use of chimneys so constructed, but use any
convenient form of chimney in carrying my Invention into effect.
Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I wish it to be understood that I claim
exclusive right to,-
Firstly, the introduction of reflecting surfaces of opaque or semi-opaque
enamel into the shades or chimneys of lamps, whatever is the nature of the
combustible substance used for producing flame in the said lamps, and whether
the said reflecting surfaces be made of white or colored enamel, and whether
the said reflecting surfaces are uncoated or coated on one or both sides. with
colored or colorless glass; also the production of the said reflecting surfaces by
painting or silvering portions of the said shades or chimnies as herein-before
described, and represented in Figures 1, 2, 3, and 4 of the accompanying
Dibitio

page_text: Secondly, the method of constructing chimneys for lamps, herein-before
lescribed, and represented in Figure 5 of the accompanying Drawing.
In witness whereof, I, the said John Davis, have hereunto set my hand
and seal, this Twenty-fourth day of November, in the year of our Lord
One thousand eight hundred and forty-five.