CERTAIN IMPROVEMENTS IN PHOTOGRAPHY
Year: 1855

page_text: LETTERS PATENT to Frederick Scott Archer, of Great Russell Street,
Bloomsbury, in the County of Middlesex, Photographer, for the Inven-
tion of "CERTAIN IMPROVEMENTS IN PHOTOGRAPHY."
Sealed the 15th January 1856, and dated the 24th August 1855.
PROVISIONAL SPECIFICATION left by the said Frederick Scott Archer at
the Office of the Commissioners of Patents, with his Petition, on the
24th August 1855.
I, FREDERICK SCOTT ARCHER, do hereby declare the nature of the said
Invention for "CERTAIN IMPROVEMENTS IN PHOTOGRAPHY" to be as follows :-
In the ordinary photographic process with collodion, the collodion is spread
upon a sheet of glass and exposed in the camera obscura, and the negative
picture thus obtained is preserved upon the sheet of glass, being generally pro-
tected by varnish. These sheets of glass occupy a considerable space, and are
liable to fracture, especially in transporting them from place to place. To
obviate this inconvenience, the collodion film has sometimes been removed from
the glass, but it is then very delicate and fragile. This film has sometimes
been cemented or attached to a sheet of paper to preserve it, but this has the
disadvantage of introducing the defects of the paper into the positive pictures
printed from the negative so prepared. By the present Invention I obviate
these various defects and disadvantages. When the negative picture has been
taken on the collodion film on the sheet of glass, and fixed and dried, I float
over it or otherwise cover it with one or more coats of a solution of gutta
percha, in benzole or chloroform, or other suitable solvent. When the solvent
has evaporated I immerse the whole in water, and I am then enabled to

page_text: remove the film or sheet of gutta percha with the collodion picture firmly
adhering to it. These films or sheets may then be preserved in a book or
portfolio, and employed for printing the positives, in lieu of glass or paper
negatives. As the collodion is thus removed from the surface which supports
it when the picture is being taken, it is possible to employ a metallic or other
opaque material in lieu of glass for that purpose.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Frederick Scott Archer in the Great Seal Patent Office on
the 20th February 1856.
- TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
SCOTT ARCHER, of Great Russell Street, Bloomsbury, in the County of
Middlesex, Photographer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of August, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Frederick Scott Archer, Her special licence that I, the said Frederick
Scott Archer, my executors, administrators, and assigns, or such others as I,
the said Frederick Scott Archer, 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 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 "CERTAIN
IMPROVEMENTS IN PHOTOGRAPHY," upon the condition (amongst others) that I,
the said Frederick Scott Archer, my executors or administrators, by an instrų-
ment in writing under my, or their, or one of their hands and seals, 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 months next and immediately
after the date of the said Letters Patent..
.
NOW KNOW YE, that I, the said Frederick Scott Archer, 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 thereof, that is to say:→
In the ordinary photographic process with collodion (which was discovered
and introduced by me in the year One thousand eight hundred and fifty-one).

page_text: the collodion is spread upon a sheet of glass, and exposed in the camera
obscura after being excited with the proper solution, and the picture is developed
and fixed, and it is then preserved upon the sheet of glass, being generally
protected by varnish. The negative pictures. thus obtained are employed for
producing positive pictures on prepared paper. These sheets of glass occupy
a considerable space, and are liable to fracture, especially in transporting them
from place to place. To obviate this inconvenience, the collodion film has
sometimes been removed from the glass, and cemented or attached to a sheet
of paper to preserve it, but this has the disadvantage of introducing the defects
of the paper into the positive pictures printed or produced from the negative
so prepared.
I
By the present. Invention I obviate these various defects and disadvantages.
The negative picture is produced in the ordinary manner upon the collodion
film on a sheet of glass, and it is fixed and dried in the ordinary manner.
then pour over it or dip it into a solution of gutta percha, and after draining
off the excess, it is dried by a gentle heat, and leaves a nearly transparent film
of gutta percha upon the collodion. If the film is not sufficiently thick, this
operation is repeated one or more times, until a sufficiently thick film of gutta
percha is formed. I then immerse the whole in water, which causes the
collodion to separate from the glass, and I then remove the film or sheet of
gutta percha with the collodion film firmly adhering or combined with it.
These films or sheets are sufficiently transparent, and are tough and flexible,
and may be handled without injury, and they may be preserved in a book or
portfolio. I employ these films for producing the positives in the same manner
that the ordinary glass negatives are employed. They may be placed with
either side in contact with the paper, according as it is wished to obtain a
correct picture or a reversed picture. In producing the negative picture in the
camera, the sheet of glass may be placed either with the collodion surface
towards the object or with the plain surface towards the object. In lieu of
glass, a smooth sheet of silver, or other metal or material which is not inju-
riously acted upon by the chemical agents employed, may be used.
The solution of gutta percha should be made with a solvent which evaporates
with rapidity, and I have found that gutta percha dissolved in benzole is well
adapted for the purpose. Benzole (or as it is sometimes called benzine) is a
volatile hydro-carbon, obtained from coal tar or from benzoic acid, as is well
known to chemists. Other volatile solvents may, however, be employed.
In lieu of wetting the plate with water to separate the film from it, it may
be wetted with other liquids, provided that they do not exert any injurious
action upon the collodion picture or upon the gutta percha. I find that water

page_text: is quite effectual for the purpose, and I therefore prefer it to other liquids. In
some cases, when the film of gutta percha is strong, it may be peeled off the
glass without the application of any liquid.
I sometimes coat or cover the plate with a film of gutta percha before
applying the collodion, which is afterwards poured upon it in the ordinary
manner. The picture is then produced and fixed, and washed and coated with
the gutta percha and removed from the plate, as herein-before described. I
thus obtain a collodion film coated on both sides with gutta percha. If the
glass plate be covered with a stout film of gutta percha before pouring the
collodion upon it, as above mentioned, the picture may afterwards be simply
varnished with any suitable varnish instead of the gutta percha solution, and
then removed from the plate, as herein-before mentioned. I, however, prefer
to employ the gutta percha solution, as first described. In all cases the
collodion film is combined with a film or films of gutta percha.
Having thus described the nature of my Invention, and in what manner
the same is to be performed, I wish it to be understood that what I claim is,
Firstly, the manufacture or production of transparent or semi-transparent
tough and flexible photographic pictures, capable of being used for the pro-
duction of other or positive pictures by coating, or covering, or combining a
collodion film with a film of gutta percha, and removing the combined films
from the glass or other surface which supports the collodion during the opera-
tion of taking the picture, as herein-before described.
Secondly, the mode or modes, herein-before described, of applying or com-
bining a film of gutta percha with a collodion film, and then removing the
combined or compound film or sheet from the glass plate or other surface
which supports the collodion during the operation of taking the picture.
In witness whereof, I, the said Frederick Scott Archer, have hereunto
set my hand and seal, this Nineteenth day of February, in the year of
our Lord One thousand eight hundred and fifty-six.
FREDERICK SCOTT ARCHER. (L.S.)
Witness,
CHARLES COWPER,
20, Southampton Buildings,
Chancery Lane, London.