IMPROVEMENTS IN LIGHTING APARTMENTS AND PASSAGES
Year: 1857

page_text: LETTERS PATENT to James Stevenson, junior, of Glasgow, in the County
of Lanark, North Britain, Merchant, for the Invention of "IMPROVEMENTS
IN LIGHTING APARTMENTS AND PASSAGES."
Sealed the 5th January 1858, and dated the 12th November 1857.
PROVISIONAL SPECIFICATION left by the said James Stevenson at
the Office of the Commissioners of Patents, with his Petition, on the
12th November 1857.
I, JAMES STEVENSON, junior, of Glasgow, in the County of Lanark, North
Britain, Merchant, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN LIGHTING APARTMENTS AND PASSAGES," to be as follows,
that is to say-
This Invention relates to the application and use, under various forms and
arrangements, of polished tile or porcelain surfaces for conveying or trans-
mitting external daylight into dark or badly lighted apartments and passages.
White porcelain tiles, such as are used for lining baths and for other
purposes, are very suitable for this purpose, and in lighting an underground
or partially underground apartment the inside of the window recess is lined
with such tiles; such a lining will transmit a large amount of external light
into the apartment, even if it is vertical, but if set at an angle the tiled surface
will light the apartment perfectly. The porcelain tiles may be disposed in
frames as well, and they may be so arranged as to transmit light from
considerable distances and by circuitous routes by reflecting from one series
to another.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Stevenson in the Great Seal Patent Office on the
12th May 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
STEVENSON, junior, of Glasgow, in the County of Lanark, North Britain,
Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of November, in the year
of our Lord One thousand eight hundred and fifty-seven, in the twenty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said James Stevenson, junior, Her special license
that I, the said James Stevenson, junior, my executors, administrators,
and assigns, or such others as I, the said James Stevenson, junior, 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
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 "IMPROVEMENTS IN
LIGHTING APARTMENTS AND PASSAGES," upon the condition (amongst others) that
I, the said James Stevenson, junior, by an instrument in writing under my
hand and seal, 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 James Stevenson, junior, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say:-
My said Invention relates to the application and use, under various forms
and arrangements, of polished tile or porcelain surfaces for conveying or trans-
mitting external daylight into dark or badly lighted apartments and passages.
White porcelain tiles, such as are used for lining baths and for other
purposes, are very suitable for this purpose, and in lighting an underground
or partially underground apartment the inside of the window recess is lined
with such tiles; such a lining will transmit a large amount of external light
into the apartment, even if it is vertical, but if set at an angle the tiled surface

page_text: will light the apartment perfectly. The porcelain tiles may be disposed in
frames as well, and they may be so arranged as to transmit light from
considerable distances and by circuitous routes by reflecting from one series
to another.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several illustrative Figures upon the explanatory
Sheet of Drawings which I have hereunto appended, for the purpose of
showing certain modifications under which my improvements may be judi-
ciously carried out in practice.
Figure 1 on my Sheet of Drawings is a vertical section of a house, showing
the application of one of my improved reflectors applied to the purpose of
lighting the basement room of the building.
Figure 2 is a section, corresponding to the lower part of Figure 1, but
drawn to a much larger scale.
Figure 3 is a plan of the arrangement, one half of this Figure being taken
above the level of the footway, and the other half below it.
The material I prefer to use as a reflecting medium is highly glazed:
"porcelain," of a pure and brilliant white colour. This material is manu-
factured in the form of tiles, which are made of about six inches square; these
tiles are extensively used for various purposes, and therefore may at all times:
be readily obtained. I have found in practice that the smooth highly polished:
surface of these tiles reflect a large quantity of the incident light, and are,
therefore, well adapted for use as reflectors. In many respects these porcelain.
reflectors are calculated to supersede the use of silvered metal or glass, which
have been ordinarily used for the purpose. Both of these materials are costly;:
the silvered surface of the metal rapidly oxidizes if air has access thereto;
and the glass reflectors are easily fractured. The porcelain reflectors are
comparatively inexpensive, the surface is very readily cleansed, and the light.
reflected therefrom is softened and devoid of the glare which characterises
light reflected from silvered surfaces. In carrying my improvements out in.
practice, these glazed tiles may be arranged in frames, which are to be:
suspended at an angle before the window of the apartment into which the:
reflected light is to be directed. The angle at which the reflector is to
be hung must be regulated according to the part of the room where it is
desired to throw the greatest body of light; the practice, however, in this:
respect is generally understood, and need not be particularly dwelt upon here..
In applying these reflectors to the lighting of the basement stories of buildings,
it is generally unnecessary to fit the tiles into frames, since the walls facing.
the window are frequently built at a convenient angle, or if not so, may.

page_text: be readily altered. In my illustrative Drawing, the example I have given
shows the application of the reflector to the vertical and angular surface of the
brickwork facing the window of the lower room. The external surface of
the brickwork A is covered with a thin and uniform layer of cement or other
adhesive materiál suitable for the purpose; upon this cement the tiles B are
laid, they are arranged in parallel rows until the whole surface is covered;
the tiles are placed close to each other, so as to present a neat and uniformly
glazed surface, the vertical as well as the angular face of the space below the.
grating C being covered in like manner; the interstices of the grating C
may be filled with glass D, and if this is done, it serves to prevent dirt or
other matters from falling upon the reflector. In Figures 1 and 2 of my
Drawing, the course of the rays of light are represented by coloured lines. In.
Figure 1, the right-hand line E represents the rays of light nearest to the
building that can reach the reflector; the incident rays here fall upon the
reflector nearly close to the vertical part, and are refracted upwards towards
the ceiling of the room. The rays represented by the next line F strike the
reflector lower down the angle, and are refracted towards the opposite wall of
the apartment; so also with the rays represented by the lines G and H,
which are respectively. refracted towards the lower part of the room. In this
manner, by varying the angle of the reflecting surface, the greater portion of
the reflected light may be directed to any part of the room, as desired. The
coloured lines drawn in 'the enlarged view, Figure 2 of my Drawing, represent:
in like manner the path of the rays of light and their angles of refraction..
The body of reflected light may be bent from its course by placing a reflector.
to receive the refracted rays from the surface B, so as to direct the light
towards a distant or out-of-the-way part of the room. If required, the light.
from this secondary reflector may, in like manner, be again caused to deviate:
from its path by means of a third reflector, and thus be made to illuminate.
places very distant from the first reflector, or which can only be lighted.
by causing the rays to traverse a circuitous route. By the judicious.
arrangement of a series of reflectors, dark or ill-lighted places in buildings may
at a comparatively small cost be rendered available for business purposes or
domestic uses..
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I may observe, in conclusion, that I do not confine or.
restrict myself to the precise details or arrangements which I have had
occasion to describe or refer to, as many variations may be made therefrom-
without deviating from the principles or main features of my Invention; but

page_text: what I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,-
First, the general arrangement and construction of reflectors for refracting
and transmitting light for lighting apartments and passages, as herein-before
described.
Second, the system or mode of reflecting light for lighting apartments and
passages by means of reflectors composed of "porcelain," or highly glazed
earthenware tiles, as herein-before described.
Third, the system or mode of reflecting and transmitting light in a circuitous
path by means of a series of reflectors composed of "porcelain," or highly
glazed earthenware, as herein-before described.
Fourth, the use and application of "porcelain," or highly glazed earthen-
ware tiles, to and for the purpose of reflecting and transmitting light, as
herein-before described.
In witness whereof, I, the said James Stevenson, junior, have hereunto
set my hand and seal, this Eleventh day of May, One thousand
eight hundred and fifty-eight.