IM- PROVEMENTS IN REFLECTORS
Year: 1862

page_text: LETTERS PATENT to William Clark, of 53, Chancery Lane, in the County
of Middlesex, Engineer and Patent Agent, for the Invention of "IM-
PROVEMENTS IN REFLECTORS."-A communication from abroad by Mr.
Louis Jacques Château, of 29, Boulevart St. Martin, Paris, formerly
Notary.
Sealed the 1st August 1862, and dated the 10th February 1862.
PROVISIONAL SPECIFICATION left by the said William Clark at the
Office of the Commissioners of Patents, with his Petition, on the 10th
February 1862.
I, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN REFLECTORS," to be as follows:-
This Invention relates to an improved reflector, composed of a series of
small plates of silvered glass or brilliant reflecting surfaces arranged one
beside the other, for the purpose of reflecting luminous rays, and of deflecting
the light; I thus obtain a much greater light at a given point. The reflectors
of this Invention are disposed so as to multiply the rays of light, and direct
them on one, two, three, or more points.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Clark, in the Great Seal Patent Office on the
8th August 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of February, in the year of our
Lord One thousand eight hundred and sixty-two, in the twenty-fifth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Clark, Her special licence that I, the said William
Clark, my executors, administrators, and assigns, or such others as I,
the said William Clark, 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 "IM-
PROVEMENTS IN REFLECTORS;" a communication from abroad by Mr. Louis Jacques
Chateau, of 29, Boulevart St. Martin, Paris, formerly Notary, upon the condition
(amongst others) that I, the said William Clark, my executors or administra-
tors, 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 performed, 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 William Clark, do hereby declare
the nature of this said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings, hereunto annexed,
and to the letters and figures marked thereon (that is to say):
This Invention relates to improved reflectors for converging and concentrating
the
rays of light on one or more parts at the same time, utilizing the whole of
the rays of reflectors which are at present in a great measure lost. The
improved convergent reflector of this Invention is formed of a series of
reflecting surfaces, the angles of which are calculated so as to direct or con-
centrate the luminous rays on one or several given points. In this manner it
will be understood that with this kind of reflector the object to be lighted
being placed at a point of convergence of the luminous rays, the observer or

page_text: operator will not be impeded in his movements by the presence of any support
of 'the reflector, and that the desired. point. only being illuminated by the
reflected rays he will never be dazzled by the light. Each angle of the
reflector may form a continuous surface, or be formed of small contiguous
facets forming an irregular surface; these facets are cut internally in the
manner of glasses and tumblers; so as to produce a great number of small.
concave surfaces, which appear convex on the side next the light. These
reflectors are constructed. either of silvered metal, or of glass; it may be
silvered or metallized in the ordinary way; the silvering is protected either
by a light coat of paint, or by a; covering of copper applied by the galvano-
plastic process, or it may be an ornamental painting or design; or, lastly, by
pasting paper thereon containing the Patentee's trade mark.. The reflectors
when made of metal have their reflecting surfaces studded with small concave
projections, produced by blocking, stamping, or otherwise. The several
arrangements of reflectors of this. Invention are applicable to various methods
of lighting, whether, with oil or schist, gas, candle, or otherwise.
In the annexed Drawing are represented several arrangements of reflectors
constructed according to this Invention; but varying in form, on account of
the different purposes to which they are to be applied..
Fig. 1 shows the reflecting surfaces in a horizontal plane, constituting the
first: arrangement.
The lower edges of these surfaces coincide with and
produce continuity of the straight line A, B.. The surfaces are represented as
being twenty in number, and of a trapezoidal form, but this number is not
essential; their union, seen in plan and elevation in Figs. 2, 3, and 4, form
when in position a polyhedral covering, the concave. side of which forms
reflectors of light. Fig. 5 represents sections of the frame of the reflector, and
in which are fixed twenty pieces of glass, looking glass, or reflecting facets of
the form shown at Fig. 1. This improved reflector is therefore. closed at one
part of its surface by the glass, while, the part opposite thereto is open. Over
the whole is placed an ordinary, reflector of a form suitable for the -purpose
required, which supports the reflecting covering, and its axis before mentioned.
Such is the construction of the first arrangement, which I term an independent
reflector...
I also make other forms of reflectors of greater simplicity, and serving as a
type for other modifications, while still adhering to a similar arrangement as
regards the number of reflecting surfaces; their form and inclination; thus the
polyhedral reflecting surface. may be of glass or crystal moulded into facets,
and of one or several polished pieces of convex form on the exterior. This
polyhedral reflecting covering may also be of metal, and formed by stamping

page_text: or blocking, and then silvered on its concave part, which is burnished. The
polyhedral reflector of whatever substance it may consist, rests on a suitable
support or tripod having a temporary top. The height of the support should
be calculated in such manner that if a horizontal plane is supposed to be
about a foot above the table, this plane should pass through the centre of the
luminous rays, which line is represented on the polyhedral reflecting surfaces
by the dotted line Q, R. Further, the luminous rays are projected vertically,
on the major axis M, N, of the plane at point S, Fig. 2. These conditions
being fulfilled, the luminous rays are caused to converge by the "reflecting.
surfaces at a distance of about 15 inches from the point of vertical. pro-
jection S.
!! :
I have also represented in the annexed Drawing several other arrange-
ments of reflectors of this Invention. Fig. 6 shows a central vertical section
of a reflector formed of planes, the inclinations of which are calculated to
illuminate at a distance of about twenty-four inches (vertically and horizontally)
from the centre, and to throw a circular band of light of a radius of twenty-
four inches.
Fig. 7 shows a central vertical section of a reflector for lighting the surface
of a billiard table, that is, to concentrate and equalize the light throughout
the surface of the board; although of especial value for such a purpose, it
may also be applied for transmitting directly a concentrated light on to a
work table, or for reading, or other purposes; or the light may be trans-
mitted on one or several surfaces at one time. Fig. 8 shows a central vertical
section of a reflector so constructed as to illuminate a circumference of from
25 to 30 yards, the luminous centre being placed about 4 or 5 yards above
the ground.
Figs. 9 and 10 show central vertical sections of two other arrangements of
reflectors for lighting billiard, dining, work, reading, and other tables, and for
lighting saloons, dining halls, workshops, and other places.
Fig. 11 shows a central vertical section of a reflector with surfaces of
various inclinations in succession, for throwing the light in concentric zones, of
continually increasing diameter. The most central reflecting zones transmit
the light to the least distance, and in proportion as the reflecting zones extend
from the centre they project the light a still further distance. This, which I
term a disc reflector, is intended for railway locomotives, ships, ports, light-
The disc reflector
houses, public squares, and other lighting purposes:
Fig. 11, is intended to be placed at the side of the luminous rays, so that the
axis of the disc shall be parallel to a horizontal line, but it may also be placed
in any other position by making the necessary opening for the passage of the

page_text: chimney. The other reflectors are intended to be placed above a light, but
they may also be fitted at the side by applying a support, represented at Figs.
12 and 13. This support may be fixed above the light, or it may be movable,
and its position regulated by means of a thumb screw. In these several
Figures, 6, 7, 8, 9, 10, and 11, a, a, are the reflecting surfaces, and b, b, the
luminous rays.
Having described the nature of this Invention, and the manner of per-
forming the same, I declare that what I claim as the Invention to be protected
by the herein-before in part recited Letters Patent is, the construction and
application of reflectors so formed as to converge the rays of light, as herein
described, as also the various modifications of the same, berein specified and
represented in the Drawings annexed.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this Soventh day of August, in the year of our Lord
One thousand eight hundred and sixty-two.
Witness,
W. G. E. SWINNOCK,
53, Chancery Lane, W.C.
W. CLARK. (L.S.)