IMPROVE- MENTS IN SUBSTITUTES FOR GLASS FOR ORNAMENTAL PURPOSES
Year: 1855

page_text: LETTERS PATENT to William Spence, of 50, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVE-
MENTS IN SUBSTITUTES FOR GLASS FOR ORNAMENTAL PURPOSES."-A com-
munication from Emmanuel Ludovico Rappaccioli, of Turin, in the
Kingdom of Sardinia, Engineer to the Corps Roval du Génie.
PROVISIONAL SPECIFICATION left by the said William Spence at
the Office of the Commissioners of Patents, with his Petition, on the
16th February 1855.
WILLIAM SPENCE, of 50, Chancery Lane, in the County of Middlesex,
Patent Agent, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN SUBSTITUTES FOR GLASS FOR ORNAMENTAL PURPOSES," being a com-
munication from Emmanuel Ludovico Rappaccioli, of Turin, in the Kingdom
of Sardinia, Engineer to the "Corps Royal du Génie," to be as follows:-
The Invention consists in substituting for glass transparent varnishes, gums,
silicates, or metallic and other compositions, formed into plates or sheets, and
capable of being applied to surfaces of various forms suitable for ornamental
purposes. These materials being flexible may be adapted to the particular
surface to be ornamented, and when applied thereto cause reflections of objects
after the manner of looking-glasses and mirrors, and serve for other ornamental
uses to which glass has heretofore been applied, as well as some uses to which
glass from its inflexibility and brittleness is inapplicable.
The following is a mode of preparing the flexible sheets of the materials
referred to, but the Invention is not confined to such mode.

page_text: Over a sheet of paper or fabric prepared with albumen one coat or several
successive coats of transparent varnish are spread; also over one of the
surfaces of a sheet of tin is spread one or several coats of anhydrous varnish.
This same surface, when the varnish is sufficiently dry, is afterwards covered
with a suitable composition for fixing the sheet of tin upon paper or fabric,
wood, or other material. There is then poured upon the other surface of the
same sheet of tin a coating of mercury, which, as in the ordinary process of
silvering looking-glasses, forms what is called an amalgam. If now the first-
mentioned sheet of varnish be applied to this amalgam or silvered surface and
turned over so that the fabric or sheet of paper may lie uppermost, it can be
made to adhere thereto by means of pressure, as in the case of glass. As
soon as this coating of varnish is found to adhere throughout its whole extent
to the amalgam or silvered surface, the paper or fabric is to be removed, which
may be done by damping or moistening it, when it will easily become detached
by reason of the coating of albumen which was originally spread over the sheet
of paper or fabric becoming dissolved.
The result is a transparent reflecting surface of the required form. In
some cases the material may be subsequently bent to the required form.
Various effects of colour and shading may be given to the material if
desired.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Spence in the Great Seal Patent Office on the
14th August 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
SPENCE, of 50, Chancery Lane, in the County of Middlesex, Patent Agent,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of February, in the eighteenth year of
Her reign, and in the year of our Lord One thousand eight hundred and fifty-
five, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Spence, Her special license that I, the said William Spence,
my executors, administrators, and assigns, or such others as I, the said
William Spence, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make, use,

page_text: exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
SUBSTITUTES FOR GLASS FOR ORNAMENTAL PURPOSES," being a communication
from Emmanuel Ludovico Rappaccioli, of Turin, in the Kingdom of Sardinia,
Engineer to the Corps Royal du Génic, upon the condition (amongst others)
that I, the said William Spence, 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
montlis next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Spence, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement (that is to say) :-
This Invention of "Improvements in Substitutes for Glass for Ornamental
Purposes" is intended to provide an economical means of ornamenting the
interiors of buildings or apartments, and situations in which it has been usual
to employ plate glass; also in situations wherein from the peculiarity of the
form of the surface to be ornamented plate glass would be inapplicable.
And the means by which this object is accomplished is by the substitution
for glass of varnishes, gums, silicates, or metallic and other compositions,
formed into plates or sheets, and rendered capable of being applied to surfaces
of various forms suitable for ornamental purposes. These materials being
flexible may be adapted to the particular surface to be ornamented, and when
applied thereto and silvered, after the manner of looking-glasses and mirrors,
cause reflections of objects; and serve for other ornamental uses to which glass
has heretofore been ordinarily applied, as well as some uses to which glass
from its inflexibility and brittleness is inapplicable.
The following is a mode of preparing the flexible sheets of the materials
referred to, but the Invention is not confined to such mode:-
Over a sheet of paper or fabric prepared with albumen one coat or several
successive coats of transparent varnish are spread; also over one of the
surfaces of a sheet of tin is spread one or several coats of anhydrous varnish.
This same surface, when the varnish is sufficiently dry, is afterwards covered
with a suitable composition for fixing the sheet of tin upon paper, or upon a
fabric, wood, or other material. There is then poured upon the surface of the
same sheet of tin a coating of mercury, which, as in the ordinary process of
silvering looking-glasses, forms what is called an amalgam. If now the first-
mentioned sheet of varnish be applied to this amalgam or silvered surface, and

page_text: turned over so that the fabric or sheet of paper may be uppermost, it can be
made to adhere thereto by means of pressure, as in the case of glass. As soon
as this coating of varnish is found to adhere throughout its whole extent to the
amalgam or silvered surface, the paper or fabric is to be removed, which may
be done by damping or moistening it, when it will easily become detached by
reason of the coating of albumen which was originally spread over the sheet of
paper or fabric becoming dissolved. The result is a transparent reflecting
surface of the required form. In some cases the material may be subsequently
bent to the required form. If desired, various effects of colour and shading
may be given to the material, instead of its being merely colourless like glass
in its ordinary use. For this purpose the varnish may be coloured, in order
to produce the effect desired.
The above described process may be also adapted and applied to the prepa-
ration of other substances, more or less transparent in their nature, and
susceptible of similar treatment, such as gelatine, gums, and various pastes or
compositions combined in several coatings or layers; also metallic compositions
and silicates, which may be procured very clear in quality and in thin sheets,
and may be covered with tin as required by means of a galvanic battery. In
all cases the general process would be similar, and the result may be obtained
by employing substances of sufficient purity and transparency.
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, I would have it understood that what I claim is,
the preparation and use of varnishes, gums, and other compositions capable of
being treated in the manner described, or otherwise, and thereby rendered
suitable for employment in substitution for glass, as described.
In witness whereof, I, the said William Spence, have hereunto set my
hand and seal, the Thirteenth day of August, in the year of our
Lord One thousand eight hundred and fifty-five.
Witness,
B. NANCARROW,
50, Chancery Lane.
WILLIAM SPENCE. (L.S.)