IMPROVEMENTS IN ILLUMINATING GRATINGS FOR ROADS, STREETS, AND OTHER WAYS, AND FOR FLOORS AND ROOFS GENERALLY
Year: 1870

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN ILLUMINATING GRATINGS FOR ROADS, STREETS, AND
OTHER WAYS, AND FOR FLOORS AND ROOFS GENERALLY, "-A communication
from abroad by Theodore Hyatt, of New York, in the United States
of America.
Sealed the 24th January, 1871, and dated the 5th December 1870.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 5th December 1870.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN ILLUMINATING GRATINGS FOR ROADS,
STREETS, AND OTHER WAYS, AND FOR FLOORS AND ROOFS GENERALLY," a commu-
nication from abroad by Theodore Hyatt, of New York, in the United
States of America, to be as follows :-
This Invention relates partly to "Improvements in illuminating
gratings suitable either for the carriage way or side walks of roads and

page_text: streets or other places where traffic is required to pass over underground
spaces requiring to be illuminated, and partly to illuminating gratings
suitable for roofs and floors generally.
According to the first part of this Invention it is proposed to construct
the main body or metal portion of the illuminating grating of steel in
order to combine strength with lightness, although any other metal may
be employed. The use of steel enables a much thinner plate to be used
and thereby facilitates the passage of light thro' the glass portions of the
grating into the space to be illuminated. The surface of the grating or
plate consists of a series of raised steel or other metallic ribs or projec-
tions disposed in any desired direction, but sufficiently near to each other
and of sufficient height to entirely protect the glass (which is fitted into
the bottom of the furrows between the ridges) from contact with the
wheels of passing vehicles or with the shoes of horses or of foot passengers.
The sides of the raised ridges may be galvanized or otherwise treated so
as to form reflecting surfaces, and the glass may be of a hemispherical
form so as to receive the light from all sides and at all angles, such light
being in a measure reflected from the sides of the ribs. These glasses
have their main portion projecting above the surface of the plate itself
in lieu of having their greater portion sunk into the said plate as hereto-
fore, but in all cases it is essential that the highest part of the glass shall
be some distance below the tops of the ridges or ribs for the purpose
herein-before mentioned.
The main strength of the gratings constructed as above described will
be in the ridges or ribs and not in the web or plate itself, hence this.
latter may be much thinner than heretofore..
In some cases it is proposed to combine together a number of smaller.
plates or gratings, say of about one foot square for example, and con-
structed with ridges and protected glasses as above set forth, such plates
being let into a metal frame provided with india-rubber seats for the
smaller plates to rest upon, whereby not only are the joints rendered
water-tight but an easy and yielding surface will be obtained which will
be better capable of withstanding the rough usages of a heavy traffic
than a more rigid surface.
According to the second part of this Invention it is proposed to cover
large areas for roofs and floors with illuminating gratings or plates of
metal having glass lights let therein, such gratings or plates being in the
form of narrow planks of any desired length and being tongue and

page_text: grooved so as to form when fitted and cemented together weather-tight
joints. These so called planks may be supported at intervals on cross
beams or bearers or on a metal frame.
It is further proposed to make small illuminating gratings or quarries
which are easily transportable and may be kept in stock to be combined
together to cover areas of any desired size, such quarries being let into
a metal frame the openings of which are too small to admit of the
entrance of a burglar, hence the necessity for securely bolting the
illuminating quarries in their places is obviated. When the said quarries
are made with ridges to protect the glasses as described under the first
part of this Invention they may when such ridges are required to run
obliquely be made of a lozenge shape in lieu of rectangular so as to fit
together end to end without intersecting the rows of lights. The end
quarries will be triangular so as to complete the junction with the
rectangular supporting or carrying frame.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Scal Patent
Office on the 5th June 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Mid-
dlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of December, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Henry Johnson, Her special license
that I, the said John Henry Johnson, my executors, administrators,
and assigns, or such others as I, the said John Henry Johnson, 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 "In-
PROVEMENTS IN ILLUMINATING GRATINGS FOR ROADS, STREETS, AND OTHER WAYS, AND
FOR FLOORS AND Roors GENERALLY," a communication to me from abroad by

page_text: planks may be supported at intervals on any suitable or ordinary cross
beams or bearers or on a metal frame.
It is further proposed to make small illuminating gratings or quarries
which are easily transportable, and may be kept in stock to be combined
together to cover areas of any desired size, such quarries being let into a 5
metal frame, the openings of which are too small to admit of the
entrance of a burglar, hence the necessity for securely bolting the
illuminating quarries in their places is obviated.
When the said quarries are made with ridges & to protect the glasses a,
as described under the first part of this Invention, they may, when such 1
ridges are required to run obliquely, as shewn in Figure 3, Sheet 2, bo
made of a lozenge shape in lieu of rectangular. One of these lozenge-
shaped quarries is shewn at A³, A', A¹, A', (Figure 3). The end quarries,
one of which is shewn at A", A", A", will be triangular so as to
complete the junction with the rectangular supporting or carrying 1
frame B.
Figure 4 is a section of Figure 3 taken along the line 1-2; and
Figure 5 is another section of the same Figure taken along the line
3-4.
Having now described and particularly ascertained the nature of 2
the said Invention, and the manner in which the same is or may
be used or carried into effect, I would observe in conclusion that
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 application and use of steel in combination with glass to
and in the manufacture of illuminating gratings for roads, streets, floors,
roofs, and other purposes, as herein-before described.
2
Second. The construction of illuminating gratings wherein the glasses
are so disposed in the metal plates that only a small portion of the glass 8
is let into the plate as compared with the portion which projects above
the surface, as herein-before described.
Third. The so constructing illuminating gratings for the purposes
herein-before referred to that the glasses therein shall be protected by
means of raised ridges or projecting ribs formed across the metal plate, 3
as hercin-before described.

page_text: Fourth. The so constructing illuminating gratings for the purposes
herein-before referred to as that the main strength of the grating shall
be comprised in the glass protecting ridges or raised ribs rather than in
the web of the plate itself, as herein-before described.
Fifth. The application and use of a number of illuminating gratings
provided with ridge protected glasses in combination with frames or
holders extending over largo areas, as herein-before described.
Sixth. The making of illuminating gratings in the form of quarries
or small tiles, and the combining of such quarries together in a frame,
the openings in which are too small to admit of the passage of a burglar,
as herein-before described.
Seventh. The application and use of india-rubber seats in metal frames
for the reception of illuminating gratings intended to bear traffic as and
for the purpose herein-before described.
Eighth. The manufacture of illuminating gratings having tongue and
grooved edges for the purpose of enabling any desired number of such
gratings to be joined together perfectly water-tight, as herein-before
described.
Ninth. The construction of lozenge-shaped illuminating quarries and
O their combination with frames or supports as and for the purpose herein.
before described.
In witness whereof, I, the said John Henry Johnson, have to
this my Specification set my hand and seal, the Second day of
June One thousand eight hundred and seventy-one.
J. HENRY JOHNSON. (L.S.)