IMPROVEMENTS IN THE PRODUCTION OF WHITE PHOTOGRAPHIC PLATES OR WHITE SURFACES TO BE USED IN PHOTOGRAPHIC PRINTING.
Year: 1875

page_text: ETTERS PATENT to William Morgan-Brown, of the Firm of Brandon
and Morgan-Brown, Engineers and Patent Agents, of 38, South-
ampton Buildings, London, and 13, Rue Gaillon, Paris, for the
Invention of " IMPROVEMENTS IN THE PRODUCTION OF WHITE PHOTOGRAPHIC
PLATES OR WHITE SURFACES TO BE USED IN PHOTOGRAPHIC PRINTING.". -Å
communication from abroad by Messieurs Horace M. Hedden and
Charles A. Hill, both of the City of Worcester, Massachusetts,
United States of America.
-
PROVISIONAL SPECIFICATION left by the said William Morgan-
Brown at the Office of the Commissioners of Patents, with his
Petition, on the 16th March 1875.
I, WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-
Brown, Engineers and Patent Agents, of 38, Southampton Buildings,
London, and 13, Rue Gaillon, Paris, do hereby declare the nature of the
said Invention for " IMPROVEMENTS IN THE PRODUCTION OF WHITE PHOTOGRAPHIC

page_text: PLATES OR WHITE SURFACES TO BE USED IN PHOTOGRAPHIC PRINTING," to be as
follows:-
This Invention for improvements in the production of white photo-
graphic plates or white surfaces to be used in photographic printing
consists in preparing the surfaces of sheet metal, preferably thin sheet
iron, cardboard, leather, wood, and other substances with a composition
that affords a white smooth surface well adapted to receive photographs,
with the advantage that it is produced at comparatively small cost.
The composition is prepared by mixing zinc, white barytes (sulphate
of baryta), kaolin, white clay, or any other suitable white pigment in a
solution of gun cotton like collodion.
The composition is poured over the surface of the plate to be prepared,
or is applied in any suitable manner. It dries and hardens rapidly, and
the surface thus obtained, when prepared with albumen or other sub-
stances of like nature mixed with sensitive preparations, is ready to
receive the photographic impression.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said William Morgan-Brown in the Great Seal Patent
Office on the 14th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 13, Ruc
Gaillon, Paris, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Sixteenth day of March, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Morgan-Brown,
Her special licence that I, the said William Morgan-Brown, my
executors, administrators, and assigns, or such others as I, the said
William Morgan-Brown, my executors, administrators, and 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

page_text: lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Islo
of Man, an Invention for "IMPROVEMENTS IN THE PRODUCTION OF WHITE
PHOTOGRAPHIC PLATES OR WHITE SURFACES TO BE USED IN PHOTOGRAPHIC
PRINTING," (a communication to me from abroad by Messieurs Horace M.
Hedden and Charles A. Hill, both of the City of Worcester, Massa-
chusetts, United States of America,) upon the condition (amongst
others) that I, the said William Morgan-Brown, my exccutors or
administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of tho 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 months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said William Morgan-Brown, 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 thercof, that is to say :-
This Invention consists in the production of white photograph plates,
other than those of porcelain, iron, or glass, and white surfaces to be
used in photographic printing.
And I now proceed to describe one mode of making these new plates,
as follows:-I prefer to take the well-known ferrotype plates, which are
made of thin sheet iron, covered with an elastic coating of baked linsced
oil for the backing, and upon which to produce the white surface, but
other metallic plates, cardboard, leather, wood, and many different
materials may be used for this purpose. I make a compound, first, of
alcohol, two and a half ounces; ether, two and a half ounces; gun
cotton, thirty grains; and white oxide of zinc, three hundred grains.
Put the gun cotton into a bottle, add the alcohol, and after the cotton
has soaked a few minutes add about three-fourths of the ether, and
shake the mixture until the cotton has dissolved, then add the remaining
portion of ether, and shake well. Put the oxide of zinc in a clean, dry,
mortar, and after pulverizing it add about one-fourth part of the collo-
dion made as above described to it; stir the oxide of zinc and the
collodion together until a smooth creamy paste is obtained, then add the
remainder of the collodion, at the same time stirring with the pestle ;

page_text: allow the compound thus prepared, and which I call the enamel, to
settle a minute, and then decant four ounces into a bottle ready for use.
When about to use the enamel shake the bottle containing it thoroughly,
allow it to settle for ten minutes, and then fill a smaller bottle with it
from which to flow the plates. Pour this enamel upon the ferrotype
plates or other surfaces precisely as ordinary collodion would be applied
to them by photographers, keeping the plates in slow motion, causing
the enamel to flow and spread evenly. About one minute after the
enamel coating has ceased to flow place the plates in soft water for ten
minutes, and then in running water (under an open water faucet) for
ten minutes longer, then immerse them while still wet in the following
solution, which I call the sizing:-Water, eight ounces; gelatine (Cox's
preferred), forty grains; arrowroot, forty grains; and sugar candy,
eighty grains. Put the gelatine in two ounces of the water to soak for
one hour, then apply gentle heat until it is all dissolved; boil the
arrowroot in six ounces of the water, and mix these two solutions
together while warm; then add the candy, and dissolve it in the mixed
solutions of gelatine and arrowroot. The enamel plates should be allowed.
to remain in this sizing solution for about ten minutes; they are then
removed and dried. This completes the mode of manufacture, and the
plates are now ready for use or sale.
1 Although the process has been described as a continuous one it
essentially consists of two parts, the preparing of the plate with a coat
of enamel, and, secondly, the sizing of the plate so prepared. The plates
may be prepared and dryed before subjecting them to the sizing process,
but the process described is found to answer best. I have thus given
one way of making the white plates, which have been found to produce
excellent results, but I do not confine the process to the particular
materials named in this formula, nor to this particular method, neither
to the pigment, vehicle, medium, enamel, sizing, nor to the proportions
named, which may be slightly modified without departing from the
spirit of the Invention.
Previous to this discovery white photograph plates, excepting those
made of glass, porcelain, ivory, and bone, were not known in the arts,
or as articles of commerce, and I therefore claim as the Invention,―
Firstly. These new articles of manufacture, namely, white photograph
plates prepared substantially as described.

page_text: And, Secondly. The combination of such plates with a sizing, sub-
stantially as described.
In witness whereof, I, the said William Morgan-Brown, have here-
unto set my hand and seal, this Fourteenth day of September,
in the year of our Lord One thousand eight hundred and seventy-
five.
WILLIAM MORGAN-BROWN. (L.S.).