IMPROVEMENTS IN THE CONSTRUCTION OF ILLUMINATING AND VENTILATING ROOFS AND GRATINGS OR PLATES, PARTS OF WHICH ARE APPLICABLE ORDINARY FOOTWAYS AND CARRIAGE WAYS
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 THE CONSTRUCTION OF ILLUMINATING AND VENTILATING
ROOFS AND GRATINGS OR PLATES, PARTS OF WHICH ARE APPLICABLE
ORDINARY FOOTWAYS AND CARRIAGE WAYS."-A communication from
abroad by Theodore Hyatt, of the City of New York, United States
of America.
TO
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 20th October 1870.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
3 of Middlesex, Gentleman, do hereby declare the nature of the said.
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF ILLUMINATING AND
VENTILATING ROOFS AND GRATINGS OR PLATES, PARTS OF WHICH ARE APPLICABLE
TO ORDINARY FOOTWAYS AND CARRIAGE WAYS," a communication to me from
.

page_text: abroad by Theodore Hyatt, of the City of New York, United States of
America, to be as follows:-
This Invention relates, firstly, to roofs for buildings, and consists in
constructing such roofs of sheet steel, having small glasses set into
perforations made in the steel to receive them.
Another improvement in roofs relates to corrugated sheet metal roofs,
and consists in the insertion therein of glasses. It is preferred to make
these glasses with expanded or button-shaped heads, so as to take a
bearing on the surface itself of the metal, and thereby obviate the labour
and expense of making special seats for such glasses. These button-
headed glasses are also applicable to illuminating gratings.
Another improvement, which is also equally applicable to gratings,
consists in making the holes in the metal plates for the reception of the
illuminating glasses larger below than on the upper side, and in forming
a slightly expanded shank on the button-headed glass, which shank
passes through the smaller end of the hole and is secured therein by
a ring of cement or putty inserted between the sides of the shank and
the inner sides of the hole. It is further proposed to combine a series
of these small button-shaped and shanked glasses or glasses of other
forms with curved or arched corrugated metal sheets for the purpose of
making arched illuminating roofs, the glasses being placed along the
lines of corrugations, and the corrugations being at right angles to the
curve or bend of the arch, consequently the curving of the plates to
the arched form has no tendency to open the joints between the glass
and the metal. The said corrugations may either be of the ordinary
curved or undulating form, or they may consist of a series of inclines or
steps having a broad and narrow surface alternately, the glass being
fitted into the broad surfaces of the steps.
The second part of this Invention relates to illuminating and ventilating
gratings for side walks or footways, and consists in making such gratings
of corrugated metal, or of metal plates having a ridge and furrow surface
formed thereon, and running obliquely or at an angle to the line of foot-
way; these oblique ridge and furrow plates may be used for lighting
and ventilating apartments or underground spaces by having apertures
made at the sides of the corrugations or ridges and above the level of
the bottom of the furrows, some or all of which apertures may be left
open or filled with glass, as preferred. These obliquely corrugated or
ridge and furrow plates when made without openings or glasses will be

page_text: found specially applicable to ordinary footways and carriage ways where
ventilation or illumination are not required, the oblique ridges and
furrows presenting a safe foothold for horses and passengers and a clean
and dry surface. In carriage ways the furrows may, if desired, be filled
with asphalte or other equivalent material.
The third part of this Invention relates to a method of forming the
surface of glass plates intended to be walked upon in such a manner as
to prevent the glass surface from becoming scratched by the feet of the
foot passengers.
One method of carrying out this part of the Invention consists in
raising a portion of the upper surface of the glass into ridges, pyramids,
knobs, lenses, or equivalent forms of projections, so as to form in fact
two surfaces, one of which is not touched by the feet, and serves to
transmit light only, whilst the other serves as the actual walking
surface.
Another method of protecting the glass consists in securing strips or
buttons of india-rubber or other equivalent protecting material upon
the face of the glass itself by means of cement or otherwise.
Another method consists in applying to the glass at suitable intervals,
near its edges metallic knobs provided with shanks, which are held to
the seat of the iron grating by the same cement which holds the glass in'
its place, or by bending the shanks underneath the glass.
The fourth part of this Invention consists in silvering the sides of the
glasses of illuminating roofs or gratings, or otherwise making them act
as reflectors. Also in enamelling, galvanizing, or otherwise treating the
metallic surfaces of illuminating gratings and sheet metal roofs, with a.
view to rendering such surfaces reflecting, the reflected light of the
upper surface being in part caught by the heads of the button-shaped
or other form of glasses inserted into such plates, and refracted, and.
consequently compelled to enter and below.
pass
The fifth part of this Invention consists in making illuminating per-
forated sheet or cast metal corrugated or ridge and furrow plates without
the use of glass, the apertures being left open and protected from rain:
by a cowl or hood cast or otherwise formed over the top of each aperture,)
and the light being forced to enter from the external reflecting surface
of the corrugation opposing it; the ray of light being thus diverted at:
right angles is projected through the aperture, and meets: an internal
T

page_text: opposing reflecting surface at the back of the aperture, which again
deflects it at right angles, and so directs it downwards into the apartment
or space beneath.
•
The sixth part of this Invention relates to what are known as. "sash
gratings," or gratings having large plates of glass let therein, and t
consists in making separate encircling seats for each plate of glass,
whereby the use of intersecting cross bars, cast in one with the frame
or grating, which strain and tend to break the casting in cooling is.
obviated.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 20th April 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Twentieth day of October, in the year
of our Lord One thousand eight hundred and seventy, in the 34th
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 "IMPROVEMENTS
IN THE CONSTRUCTION OF ILLUMINATING AND VENTILATING ROOFS AND GRATINGS OR
PLATES, PART OF WHICH ARE APPLICABLE TO ORDINARY FOOTWAYS AND CARRIAGE
WAYS," a communication to me from abroad by Theodore Hyatt, of the
City of New York, United States of America, upon the condition
(amongst others) that I, the said John Henry Johnson, my executors
or administrators, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause the

page_text: 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 John Henry Johnson, 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:-
My said Invention relates, firstly, to roofs for buildings, and consists
in constructing such roofs of sheet steel or other sheet metal having
small glasses set into perforations made therein to receive them.
Another improvement in roofs relates to corrugated sheet metal roofs,.
and consists in the insertion therein of glasses. I prefer to make these
glasses with expanded or button-shaped heads, so as to take a bearing-
on the surface itself of the metal, and thereby obviate the labour and
expense of making special seats for such glasses. These button-headed
glasses are also applicable to illuminating gratings.
i
Another improvement, which is also equally applicable to gratings,
consists in making the holes in the metal plates for the reception of the
illuminating glasses larger below than on the upper side, and in forming
a slightly expanded shank on the button-headed glass, which shank
passes through the smaller end of the hole, and is secured therein by a
ring of cement or putty inserted between the sides of the shank and the
inner sides of the hole. I further propose to combine a series of these
small button-shaped and shanked glasses or glasses of other forms with
curved or arched corrugated metal sheets for the purpose of making
arched illuminating roofs, the glasses being placed along the lines of
corrugations, and the corrugations being at right angles to the curve or
bend of the arch, consequently the curving of the plates to the arched
form has no tendency to open the joints between the glass and the
metal. The said corrugations may either be of the ordinary curved or
undulating form, or they may consist of a series of inclines or steps.
having a broad and narrow surface alternately, the glass being fitted into
the broad surfaces of the steps.
The second part of my Invention relates to illuminating and ventilating
gratings for side walks or footways, and consists in making such gratings
of corrugated metal, the corrugations running by preference obliquely or
at an angle to the line of footway. These oblique corrugated plates may
be used for lighting and ventilating apartments or underground spaces

page_text: by having apertures made by preference at the sides of the corrugations,
and above the level of the bottom of the furrows, some or all of which
apertures may be left open or filled with glass, as preferred. These
obliquely corrugated or ridge and furrow plates when made without
openings or glasses will be found suitable for ordinary footways and
carriage ways where ventilation or illumination are not required, the
oblique ridges and furrows presenting a safe foothold for horses and
passengers, and a clean and dry surface. In carriage ways the furrows
may, if desired, be filled with asphalte or other equivalent material.
The third part of my Invention relates to a method of forming the
surface of glass plates intended to be walked upon in such a manner as
to prevent the main portion of the glass surface from becoming scratched
by the feet of foot passengers.
One method of carrying out this part of my Invention consists in
raising a portion of the upper surface of the glass into ridges, pyramids,
knobs, lenses, or equivalent forms of projections or protuberances so as
to form in fact two surfaces, one of which is not touched by the feet and
serves to transmit light only, whilst the other serves as the actual
walking surface.
Another method of protecting the glass and obtaining a good foothold
consists in securing strips or buttons or caps of india-rubber, metal, or
other protecting material either upon the surface of the glass itself or in
grooves or recesses sunk into the face of the glass, or (if used in the form
of caps) the said caps may be fitted on to protuberances on the glass,
cement or other suitable means being employed for securing the
protecting material to the glass.
Another method consists in applying to the glass at suitable intervals
metallic strips or knobs provided with shanks, which may be held to the
seat of the iron grating by the same cement which holds the glass in its
place, or by bending the shanks underneath the glass. Or the said
knobs may be formed on metal clips or corner pieces, which are slipped
over the edges or corners of the glass, and held in position by the seating
and cement which serves to secure the glass.
The fourth part of my Invention consists in silvering the edges of the
glasses used in illuminating roofs or gratings, or otherwise making the
sides or edges of such glasses act as reflectors. I also propose to enamel,
galvanize, or otherwise treat the metallic surfaces of illuminating gratings
and sheet metal roofs with a view to rendering such surfaces reflecting,

page_text: the reflected light of the upper surface being in part caught by the heads
of the button shaped or other form of glasses inserted into such plates,
and refracted and consequently compelled to enter and pass below.
The fifth part of my Invention consists in making illuminating per-
forated sheet or cast metal corrugated or ridge and furrow plates for
roofs and side walks without the use of glass, the apertures being formed
in the sides of the corrugations, and left open and protected from rain
by a cowl or hood cast or otherwise formed over the top of each aperture,
and the light being forced to enter from the external reflecting surface
of the corrugation opposing it; the ray of light being thus diverted is
projected through the aperture, and meets an internal opposing reflecting
surface at the back of the aperture, which again deflects it and so directs
it downwards into the apartment or space beneath. By forming the
apertures in the sides of the corrugations I exclude rain and dirt, and by
making the surfaces in front of and behind these apertures reflecting
surfaces I compensate for any loss of direct rays of light which may arise
from the peculiar position of the apertures.
And in order that my said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheet of Drawings, the
same letters of reference indicating corresponding parts in all the corre-
sponding Figures.
Figures 1 to 6 (Sheet 1) inclusive illustrate the first head of my
Invention. Figure 1 is a sectional elevation of a portion of a sheet steel
roof, a being the sheet steel, and b, b, small glasses set into openings
made in the sheet metal. This roof is composed of flat sheet metal, but
Figures 2 and 3 represent portions of roofs of sheet steel or other sheet
metal wherein the metal is strengthened by being corrugated, so as to
form a series of inclines or steps, and the glasses b, b, are set into the
broader faces of such corrugations. In Figure 3 the said corrugated
plates are shewn as being curved or bent to an arched form, the lines of
corrugations being disposed transversely to the curve or bend of the
plate, so that the seatings for the glasses 6 will not be opened or sprung
by the bending of the plates. The form of corrugations may be varied,
but those of the form I have illustrated in Figures 2 and 3 will answer
well in practice. The glasses in Figures 1, 2, and 3 are shewn with.
expanded or button-shaped heads, as I find that to be the most useful.
form, the expanded portion of the head taking a bearing upon the

page_text: cement on the surface of the metal itself, as shewn at c in Figure 1,
without any special seat being prepared. Although I prefer this form of
glass I do not confine myself thereto, as other convenient forms may be
adopted. Figure 4 represents a piece of sheet steel or other sheet metal a
having a glass b secured therein by means of a rim or shank d made
larger at the bottom than at the top, which is inserted into a corre-
spondingly shaped or tapered hole in the metal plate a, the intervening
space between the expanded shank or rim of the glass and the sides of
the hole being filled in with putty or cement c. In Figure 4 the glass is
shewn hollow for the shake of lightness, and is fitted into a sheet metal
plate suitable for roofing purposes, but in Figure 5 I have shewn a
similar glass made solid and fitted into a strong cast-iron plate a suitable
for a footway. Figure 6 shews another light form of roof glass of a
concavo-convex hemispherical form, the said glass being set in a seat,
which is specially sunk or recessed in the metal sheet a, and secured
thereon by a ring of putty or cement c. By enamelling, galvanizing,
or otherwise treating the upper and under surfaces of the plate a in
Figures 1 to 6 inclusive, so as to make such surfaces capable of reflecting
rays of light, I am enabled when the apertures in the plates are provided
with glasses to increase the amount of light transmitted through them.
Figures 7 and 8 (Sheet 1) illustrate the second head of my Invention,
and represent respectively a corrugated illuminating footway plate or
grating, and a ridge and furrow plate made solid without perforations
or glasses suitable for ordinary footways or carriage ways. The lines of
corrugations or ridges a, a, in Figures 7 and 8 are by preference disposed
obliquely to the general line of way in order to improve the foothold,
but I do not confine myself to that disposition, as the corrugations or
ridges and furrows may run at right angles or transversely to the line of
way. Figure 7 shews the application of glasses b, b, to illuminating
apertures made in the corrugations, and by preference in the sides of the
corrugations, so as to expose the glasses to as little wear as possible, and
to keep them free from dirt with a view to the admission of rays of light
to the apartment or space underneath the grating or plate, as shewn by
the red lines and herein-after explained. In some cases where free
ventilation is required some or all of these glasses 6 may be omitted.
By placing the openings and glasses in the sides of the corrugations,
as shewn, they will not be materially interfered with by the feet of
pedestrians.

page_text: The third head of my Invention is illustrated by Figures 9 and 10
(Sheet 1), and Figures 11 to 18 inclusive on Sheet 2 of my Drawings.
Figures 9 and 10 (Sheet 1) represent respectively a section and plan of
a glass plate or tile the surface of which is formed with ridges b', b', so
as to prevent the entire surface of the glass from becoming scratched by
the feet of foot passengers. These glasses may be fitted into metal
gratings or plates of any convenient size and formation, and the mode
of forming the surface of the glass may be varied considerably whilst
still accomplishing the desired two-fold object, namely, admitting light
through the glass by partially protecting its surface from scratches, and
of presenting a safe and secure foothold to pedestrians. Figures 11 and
12 (Sheet 2) illustrate in plan and side elevation another form of glass
for the same purpose wherein a series of rounded projections or lenses
,, are formed on the flat surface of the glass b, so as to present a
foothold, and at the same time protect the flat illuminating surface of
the glass from scratches. Figures 13 and 14 are similar views of a
similar glass with a modified form and arrangement of the protecting
knobs or protuberances, consisting of one or more lenses b¹ in combination
with studs or buttons 6", 6", cast like the lenses 6' on the surface of the
glass. In Figures 15 and 16 I have represented a plate of glass b,
having its surface protected for the purpose before mentioned by means
of strips e, e, of india-rubber, metal, or other protecting material
cemented by preference in a diagonal or oblique direction thereon, such
strips of protecting material being either secured to the flat face of the
glass or let into grooves or recesses sunk therein. Or in lieu of strips
the protecting material may be applied in other forms, such, for example,
as round or other shaped studs or knobs e¹, e¹. In some cases the india-
rubber or other protecting material may be more securely held to the
glass by making it in the form of an inverted trough or cap, which is
fitted over ridges or projections of corresponding shape cast on the
surface of the glass in order to form a good foothold and to protect the
glasses from fracture by blows. Figures 17 and 18 represent in plan'
and section respectively a square of glass 6 protected by means of metal
knobs or projections fif, fitted round the edge of the glass in com-
bination with one or more glass knobs or projections 6' cast on the glass
itself. These metal knobs f are represented as being formed on or
attached to metal clips g, g, fitting and overlapping the four corners of
the glass, the edges of the glass at the corners being by preference.
b

page_text: recessed slightly, as shewn by dotted lines in Figure 17, in order that
the metal sides of the clip pieces g may be flush with the edges of the
glass, and so fit accurately into the main seating h, h, (Figure 18), and
be therein secured by cement or otherwise. I prefer to interpose between
the clip pieces g carrying the knobs fand the surface of the glass a layer
or cushion of india-rubber, or other suitable yielding material in order to
deaden the effect on the glass of any blow which the said knobs might
receive.
:
Figures 19 and 20 illustrate the fifth head of my Invention, and
represent cast metal corrugated illuminating and ventilating plates or
gratings wherein the use of glass is dispensed with. A series of
openings a, a, are made along one or both sides of the corrugations or
ridges, and when made only along one side such openings are by
preference made on the side which receives the most direct rays of light,
in order that such rays may be so reflected as to be finally deflected
through the openings and down into the apartment or space beneath,
as shewn by the red lines. For this purpose the side i of one ridge
opposite the perforations a in the next ridge is galvanized or otherwise
treated so as to cause it to reflect the light from its surface through the
openings a, which light strikes the internal reflecting surface c behind
the said openings, and is thence reflected down into the apartment or
space below, as illustrated by the red lines in these two Figures and in
Figure 7 (Sheet 1). This mode of illuminating is equally applicable
whether the corrugations be curvelinear (as shewn in Figures 7 and 19)
or angular (as shewn in Figure 20). In Figure 19 I have shewn a small
hood or projecting ledge k cast over each opening a for the purpose of
keeping out the rain and preventing the entrance of mud and dirt into.
the openings. By placing these openings in the side or sides of the corru-
gations and a little below the tops of the same, it is obvious that the
plates may be walked over without the said openings becoming clogged a
up, which they would be more liable to if the plates were merely
ordinary perforated plates or gratings, but by adopting the form of
corrugation and aperture shown in Figure 20 the hood or projection k
may be dispensed with.
Having now described and particularly ascertained the nature of my a
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

page_text: 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 constructing of roofs for buildings of sheet steel or other
suitable sheet metal having illuminating apertures made therein covered
with glass, substantially as herein-before described.
Second. The constructing of roofs for buildings of corrugated sheet
steel or other suitable sheet metal having illuminating perforations made
therein covered with glass, substantially as herein-before described.
Third. The application of the peculiar stepped form of corrugation
shown in Figures 2 and 3 of my Drawings to sheet metal plates intended
to be used as illuminating roofs for the purpose specified.
Fourth. The construction of glasses for illuminating purposes with
expanded or button-shaped heads and with shanks or stems, whereby
such glasses can be secured in perforations made in metal sheets or
plates without any special seating being required in the metal, sub-
stantially as herein-before described and illustrated by Figure 1 of my
Drawings.
Fifth. The construction of illuminating glasses provided with button-
shaped heads and with expanded shanks or stems, and the combination
of such glasses with metal sheets or plates having tapered holes made
therein, substantially in the manner and for the purpose hercin-before
described and illustrated by Figures 4 and 5 of my Drawings.
Sixth. The construction and use of corrugated illuminating plates or
gratings for side walks or footways having apertures made therein pro-
vided with glasses, substantially as herein-before described and illustrated
by Figure 7 of my Drawings.
Seventh. The construction and use of glass plates, tiles, or slabs
intended to be walked upon having their upper surfaces formed with
projections, and hollow for the purpose of protecting the main portion
of the glass from being scratched or worn by traffic, substantially as
herein-before described and illustrated by Figures 9 to 14 inclusive of
my Drawings.
Eighth. The attaching to the exposed surface of glass plates intended
to be walked upon of strips or buttons of india-rubber, metal, or other
suitable protecting material for the purpose of preventing the exposed
surface of the glass from being scratched or worn, substantially as

page_text: herein-before described and illustrated by Figures 15 and 16 of my
Drawings.
Ninth. The combination with glass plates intended to be walked upon
of protecting strips or knobs of metal or other suitable protecting
material which are retained upon the exposed surface of the glass not by
adhesion to the glass itself, but by being secured to the frame which
holds the glass, substantially as herein-before described with reference to
Figures 17 and 18 of my Drawings..
Tenth. The silvering of the edges of the glasses intended to be used
in illuminating roofs or gratings, or otherwise making the sides or
edges of such glasses act as reflectors for the purpose herein-before
described.
Eleventh. The enamelling, galvanizing, or otherwise treating the
metallic surfaces of illuminating gratings and sheet metal roofs when
the apertures therein are provided with glasses with a view to rendering
such surfaces reflecting..
Twelfth. The construction and use of ventilating and illuminating
corrugated plates or gratings having apertures made in the sides of the
corrugations, and having the whole or portions of the external and
internal surfaces of the plates made reflecting, substantially as and for
the purpose herein-before described and illustrated by Figures 19 and 20
of my Drawings.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, this Nineteenth day of
April One thousand eight hundred and seventy-one.
6