CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF TRANSPARENT PICTURES
Year: 1878

page_text: LETTERS PATENT to Robert James Coningsby, of Croydon, and Albert Grover,
of Mitcham, both in the County of Surrey, for the Invention of "CERTAIN
IMPROVEMENTS IN THE MANUFACTURE OF TRANSPARENT PICTURES."
1010
Sealed the 110
1141
March 1973,
and dated the 25th September 1878.
PROVISIONAL SPECIFICATION left by the said Robert James Coningsby and
Albert Grover at the Office of the Commissioners of Patents on the 25th Sep-
tember 1878.
ROBERT JAMES CONINGSBY, of Croydon, and ALBERT GROVER, of Mitcham, both
in the County of Surrey. "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF
TRANSPARENT PICTURES."
Our Invention relates to improvements in the manufacture of transparent pictures,
and the improvements consist in the employment of plaster of Paris so treated by
wax or a similar oleaginous substance as to form a semi-transparent. substance,
which substance is poured into moulds properly prepared with the required depths
to produce the required shadows or relief.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert James Coningsby and Albert Grover in the Great Seal Patent
Office on the 25th March 1879.
ROBERT JAMES CONINGSBY, of Croydon, and ALBERT GROVER, of Mitcham, both
in the County of Surrey. "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF
TRANSPARENT PICTURES."
Our Invention relates to improvements in the manufacture of transparent pictures
(litchbilder), whereby the same can be produced at a much lower cost than by the
systems at present resorted to in Germany and elsewhere.
By our improvements we dispense with the clay at present used, and the trouble-
some process of preparing the same, and our Invention consists in the employment
in place thereof of fine plaster of Paris, which substance we mix with water, and
pour into plates, matrices, or moulds of wax or other suitable material prepared in
such a way as to give the desired relief and design, taking care to cover the impres-
sion, so as to produce when the plaster is set a very thin casting. As in the case of
large pictures the thinness of the castings obtained by our process renders it difficult
to separate the same from the plates, matrices, or moulds used for the purpose, we
plunge the castings, plates, matrices, or moulds together into a bath of hot wax or
other suitable oleaginous or gelatinous matter (usually the same as that from which
the plates, matrices, or moulds are made), and the latter melting, peels off, leaving
the plaster in the shape of a very thin casting, as before described. Plaster of Paris
when dry being perfectly opaque, our next process is to dip the castings obtained as
herein-before described into a preparation of hot wax (stearine wax, or some other
suitable oleaginous or gelatinous substance), which, passing into and filling up the
pores of the plaster, renders the same semi-transparent, and the picture appears with
every delicate outline, shade, and relief obtained by the more costly and troublesome
process or processes at present employed in Germany and elsewhere. In some cases
we use water for the purpose of filling up the pores in the plaster of Paris castings,
and thus obtain semi-transparent pictures; this we do either by periodically
damping the pictures, or by attaching to them small troughs or other receptacles for
water or liquid used for the purpose, which by the operation of a natural law, that
of absorption, suffuses itself equally over the pictures, and gives the required semi-
transparency. By mixing scent, scents, or disinfectants with the water or liquid
used we either perfume, disinfect, or render more wholesome the atmosphere in
which our pictures are placed. The pictures so prepared and used will serve to
perfume or disinfect cabs, hospitals, sick and other rooms.
We claim that by our process the white and dark lines in the pictures, obtained
hitherto by the more costly processes adopted in Germany and elsewhere for the
production of porcelain and similar transparencies, which have a yellowish hue in
places in which a pure white would add to the effect and harmony of the pictures,
are seen more distinctly in contrast in the pictures or transparencies obtained by
our processes:
The castings obtained as herein-before described being very brittle, we place them
either between sheets of glass, filling the spaces around the edges thereof with
plaster of Paris or other suitable substance, or we fasten them to a sheet or sheets
of glass by means of some suitable substance which allows of several pictures or
transparencies being combined so as to form screens, windows, window and other
blinds, shades, curtains, and the like.
When stained glass instead of white is used for any of the before-mentioned
purposes, our pictures can be adapted to any or all of the ornamental purposes for
which the more expensive stained glass pictures, are now used.
Our pictures (that is to say, pictures obtained by our process) can be painted in
colours (either water or oil), which can be so fixed by immersion into the hot wax
or similar substance, herein-before described, as to be imperishable except with the
decay or destruction of the pictures themselves.

page_text: The
We also have another method of throwing tints through our pictures. We make
blinds or curtains of coloured tissue paper or other suitable substances of one or
more colours and shades; these we either fasten or fix to our pictures or roll up and
down by the band or the usual mechanical methods at the back of the same.
effects of either daylight or artificial light of any kind passing through the blinds or
curtains so made and placed are pleasing to the eye, producing peculiarly soft and
mellow tintings.
The borders or frames for our pictures are made of different designs, and of the
same materials and in the same manner as the pictures themselves, with which
they form a whole.
The pictures produced by our process can be applied to a great number of useful
and ornamental purposes, amongst which may be enumerated for ornamental
windows, pictures to hang in the light, for lamp and other shades, for window
curtains or blinds, for skylights, for hall doors, conservatories, libraries, and other
purposes where subdued light is desired; for illuminations at festivals during times
of public or private rejoicings; for advertising during both day and night, during
the latter by means of a strong light or lights placed behind the pictures, which
illuminate and fully display the same; for slides for magic lanterns, and numerous
other purposes.
Having now described our said Invention, and the best means with which we are
acquainted for carrying the same into effect, we wish it to be understood that we
do not confine ourselves to the precise details herein laid down, as the same may be
varied without departing from the principle of our Invention, but what we do claim
is,—
The employment of plaster of Paris and wax or other suitable oleaginous or
gelatinous substance for the manufacture of transparent or semi-transparent or light
pictures, as herein-before described.
•
In witness whereof, we, the said Robert James Coningsby and Albert Grover,
have hereto set our hands and seals, this Twenty-fourth day of March, in the
year of our Lord One thousand eight hundred and seventy-nine.