IMPROVEMENTS IN TRANSLUCENT PLATES OR SHEETS FOR USE AS SUBSTITUTES FOR GLASS IN ROOF LIGHTS AND OTHERWISE
Year: 1882

page_text: LETTERS PATENT to William Kennedy, of Glasgow, in the County of Lanark,
North Britain, for an Invention of "IMPROVEMENTS IN TRANSLUCENT PLATES
OR SHEETS FOR USE AS SUBSTITUTES FOR GLASS IN ROOF LIGHTS AND
OTHERWISE,"
PROVISIONAL SPECIFICATION left by the said William Kennedy at the
Office of the Commissioners of Patents on the 6th November 1882.
WILLIAM KENNEDY, of Glasgow, in the County of Lanark, North Britain,
"IMPROVEMENTS IN TRANSLUCENT PLATES OR SHEETS FOR USE AS SUBSTITUTES
FOR GLASS IN ROOF LIGHTS AND OTHERWISE
"
This Invention has for its object the production of improved translucent plates
or sheets to be used as substitutes for glass in roof lights and otherwise. The
improved plates or sheets will not transmit so much light as clear glass but will
allow as much to pass as will be sufficient for many purposes and for various
situations, whilst they will not be so easily broken as glass and will be lighter thun
glass of the thickness considered necessary for roof lights.
The improved translucent plates or sheets consist of perforated sheet zinc or of
any suitable perforated sheet metal or of wire gauze, the openings through which
are closed with gelatin, varnish, or other suitable translucent substance or
composition Or sheets of paper or of woven fabric may be cemented or otherwise
attached to the perforated metal or wire gauze such paper or fabric being rendered
translucent by means of gelatin, wax, or varnish before or after being attached to
the metal. When gelatine is used as the translucent substance it should be treated
with an external coat of varnish to protect it from the action of moisture.
The translucent substance may be colored or rendered ornamental by means of
transparent coloring matters. The improved plates or sheets may be used for a
great variety of purposes, amongst which may be mentioned lanterns, window
screens, fire screens, and illuminated advertisements.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Kennedy in the Great Seal Patent Office on the 4th May
1883.
WILLIAM KENNEDY, of Glasgow, in the County of Lanark, North Britain,
"IMPROVEMENTS IN TRANSLUCENT PLATES OR SHEETS FOR USE AS SUBSTITUTES
FOR GLASS IN ROOF LIGHTS AND OTHERWISE
"
My said Invention has for its object the production of improved translucent
plates or sheets to be used as substitutes for glass in roof lights and otherwise.
My improved plates or sheets will not transmit so much light as clear glass, but
will allow as much to pass as will be sufficient for many purposes and for various
situations; whilst they will not be so easily broken as glass, and will be of less.
weight than glass of the thickness considered necessary for roof lights.
My improved translucent plates or sheets consist of perforated sheet zine, or of
any suitable perforated sheet metal, or of wire gauze, the openings through which
are closed with gelatin, varnish, or other suitable translucent substance or
composition. Or sheets of paper or of woven fabric may be cemented or
otherwise attached to the perforated metal or wire gauze, such paper or fabric
being rendered translucent by means of any suitable substance such as gelatin,
wax, varnish, drying oil, or soluble glass, before or after being attached to the metal.
When gelatin or soluble glass is used as the translucent substance it should be
treated, when dry with an external coat of varnish to protect it from, the action
of moisture; and in the case of gelatin a small proportion of glycerin may be
mixed with it to counteract its tendency to shrink.
In practically carrying out my Invention according to one modification I first
prepare the perforated zinc plate by rubbing both surfaces with a piece of
sandstone. I then apply a coating of spirit varnish or other hard clear varnish
and place on the plate a sheet of thin tracing paper of the kind used by mechanical
draughtsmen, taking care to stretch it evenly and without wrinkles. Or the paper
may be laid out smoothly on a flat surface and the varnished zinc plate be placed
upon it and be pressed to secure adhesion at all unperforated parts. When the
work is sufficiently dry a coat of varnish is put on the outer surface of the paper;
and if the plate is desired to be of special strength a second sheet of tracing paper
is applied upon the first and is varnished on its outer side. To render the plate
stronger and more durable additional coats of varnish may be applied on both
sides.
66
According to a second modification a sheet or plate of zinc having perforations
which are by preference of the size known as N° 8," is treated with a coating
consisting of a strong solution of silicate of soda or soluble glass so that the
solution may fill the perforations. This may be effected by placing the zinc plate
on a slab of plate glass placed horizontally or on a smoothly surfaced slab of slate,
marble, iron, or other suitable material to which the soluble glass will not adhere.
One or two coats of the solution having been applied the slab is placed before or
beneath a fire or heat is otherwise applied to dry the outer surface of the solution,
after which the zine plate is removed from the slab and its other surface is dried.
When the soluble glass is quite dry both sides are coated with copal varnish or
other suitable varnish.
The translucent substance may be colored or rendered ornamental by means of
transparent coloring matters. The improved plates or sheets may be used for a
great variety of purposes, amongst which may be mentioned lanterns, window
screens, fire screens, and illuminated advertisements. Ornamental devices may be

page_text: applied by means of thin colored gelatin; or the paper or woven fabric may
previously to being applied to the zinc have colored or other devices produced
upon it by printing or otherwise. Ornamental devices may be formed by
cementing pieces of colored glass upon the perforated metal sheet or plate; and
when the ornamentation is effected in this way a sheet of thin paper or woven
fabric may be attached or cemented over the glass, and bo varnished on the outer
sido.
Having thus particularly described my said Invention and the manner of
performing the same I have to state that I do not restrict myself to the
precise details herein described but that what I believe to be novel and original
and claim as the Invention secured to me by and in terms of the hereinbefore in
pait recited Letters Patent is
The combination of perforated metal sheets or plates with translucent paper,
woven fabric, gelatin or other suitable translucent substance substantially in the
manner and for the purposes hereinbefore described.
In Witness whereof I, the said William Kennedy, have hereunto set my
hand and seal this third day of May in the year of our Lord One thousand
eight hundred and eighty-three
Witness,
EDMUND HUNT
Patent Agent
Glasgow.
W KENNEDY (L.S.)
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