AN IMPROVED METHOD OF PRODUCING AND USING SURFACE BLOCKS FOR LINE AND PHOTOGRAPHIC PRINTING PROM NATURE
Year: 1872

page_text: LETTERS PATENT to Robert Henelade Courtenay, of Meyrick Road,
Clapham Junction, in the County of Surrey, Heliographic Engraver,
for the Invention of "AN IMPROVED METHOD OF PRODUCING AND USING
SURFACE BLOCKS FOR LINE AND PHOTOGRAPHIC PRINTING PROM NATURE."
Scaled the 25th March 1873, and dated the 27th September 1872.
PROVISIONAL SPECIFICATION left by the said Robert Henclade
Courtenay at the Office of the Commissioners of Patents, with his
Petition, on the 27th September 1872.
I, ROBERT HENELADE COURTENAY, of Meyrick Road, Clapham Junc-
tion, in the County of Surrey, Heliographic Engraver, do hereby declare
the nature of the said Invention for "AN IMPROVED METHOD OF PRODUCING AND
USING SURFACE BLOCKS FOR LINE AND PHOTOGRAPHIC PRINTING FROM NATURE," to
be as follows :-
This Invention has for its object an improved method of preparing
printing surfaces by photographic means, and the production of prints
from those surfaces. I use for the production of the negative or positive
by which the printing surface is obtained a collodion holding in
suspension a powder, such as silex, wheat flour, or other faranaccous

page_text: meal, which shall confer upon the negative when viewed by transmitted
light a certain degree of granularity, both in the deepest shadows and
the lights; and from a cliché possessing this granularity I make a print
on a sensitive film composed of gelatine or other organic matter and a
salt of chromic acid, such as bichromate of potash, and then with
pressure I obtain a positive of the subject in metallic relief on a smooth
plate of metal, by which the details of the image are impressed upon or
into the metallic plate, and which after the complete removal of the
image by which it was impressed is thus converted into a surface
capable of yielding prints at an ordinary printing press.
The second part of my Invention has reference to the method by
which a plate, prepared as before mentioned, is used for the production
of prints. From the same cliche as that from which I make the printing
surface or from one similar to it I make another print of the before
mentioned gelatinous composition which shall be the reverse of that by
which the metallic plate was impressed, the details of which are reversed
in their order so as to permit the print to be used as an overlay in the
tympan of the press, so that when the raised portions of the printing
plate are inked and an impression is about to be taken the reversed
picture which is fixed on the tympan shall by its inequality of surface
cause a greater degree of pressure to be applied to the deepest shadows
and less to the lights of the picture.
I also use the printing block for line work, such as engravings,
drawings, &c., without clearing or cutting away or deepening the lights,
by depositing zinc upon it by the ordinary well known means, and then
treating it with the mixture of the solutions of nut galls, gum, and
phosphoric acid used in printing from zinc plates, after which it is inked
and printed from in the usual way at the type press or lithographic
printing machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent, 3
filed by the said Robert Henelade Courtenay in the Great Seal
Patent Office on the 26th March 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
HENELADE COURTENAY, of Meyrick Road, Clapham Junction, in the
County of Surrey, Heliographic Engraver, send grecting.
3

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of September, in
the year of our Lord One thousand eight hundred and seventy-two, in
the thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Henelade Courtenay,
Her special licence that I, the said Robert Henelade Courtenay, my
executors, administrators, and assigns, or such others as I, the said
Robert Henelade Courtenay, 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 "AN IMPROVED METHOD OF PRODUCING AND USING
SURFACE BLOCKS FOR LINE AND PHOTOGRAPHIC PRINTING FROM NATURE," upon the
condition (amongst others) that I, the said Robert Henelade Courtenay,
my executors 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 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 Robert Henelade Courtenay, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement :-
This Invention has for its object the preparation of printing surfaces
by means of photography and hydraulic pressure, and by its means
plates or blocks are engraved, surface or intaglio, that can be printed
from by any of the presses in ordinary use, the subjects being taken
direct from nature or otherwise.
In the first place I prepare a suitable collodion containing oleate of
silver and a powder that will not act injuriously to the collodion or silver
bath; the powder I use for producing a negative for the purpose of
giving a certain amount of granularity to the finished surface block is
corn meal or any other similar farinaceous powder that will not disturb
the delicacy of the negative film through the repeated washings the
same is subjected to, or a mineral powder can be used, such as powdered
glass or pure silex obtained from silicate of potash or ammonia. In

page_text: fact any powder can be used that will not injure the chemistry in the
production of the plates. The object of the use of the powder being to
produce a kind of stipple in the negative film of a photograph from
nature, and that of the oleate of silver to give sensitiveness and vigour
to the negative, combined with a certain neat appearance of the film
that assists to check the too energetic action of the light through the
transparent parts of the negative in the production of the positive, which
I prefer to take by transmitted light through the camera with or from
the negative in grain before mentioned.
I do not confine myself to the use of a collodion containing any
particular powder for the purpose of producing a grain or stipple; I
sometimes use a composition in which is mixed a suitable powder for
producing the granularity required; I also use plates prepared with
suitable grain according to the purposes required, either artificially or
done by hand, which I afterwards impress on the soft metal plates. By
this method I claim originality in producing photo-mezzotint, and photo-
aquatint, as also line subjects to imitate chalk drawings, by hydraulic
pressure.
A soft metal plate is prepared with a grain suitable for the intended
design, after which a relief photograph is transferred to the plate of a
suitable thickness, the gradations of the photograph filling certain
portions of the grained plate in lieu of the engraver scraping away the
lights and tones in the usual manner; a cast is now taken with gutta
percha and electrotyped in the usual way, either solid or backed up with
type metal, after which the face is cleaned, and the plate is ready for
the press.
I now proceed to take a transparent positive as follows:-I take a
suitable collodion without the powder, the camera being adjusted to the
size of plate or block required, and take a transparency in the usual way
from the granulated negative. In the positive taken as above there are
those conditions in it that are requisite for the production of a surface
block in stipple, or a grained plate can be used instead of the positive
transparency in grain, the negative relief being transferred and impressed
on to the grained plate, or a smooth plate can be used with a grain in
the composition used for the negative relief, to obtain which I prepare a
gelatinous compound of such a nature that when acted upon by light a
photograph is obtained in negative relief from the positive above
described.

page_text: The composition I use and find most convenient is a mixture of
gelatine, sugar, tragacanth, and starch, and a coloring matter, usually
carbon, in fine powder or liquid Indian ink.
I do not confine myself to one or any particular ingredient for the
production of the photograph; any compound can be used in combination
with chromic acid or any of its salts, such as bichromate of potash or
ammonia, or any other sensitising agent.
I do not claim originality in producing a photograph in relief by using
one or any of the substances herein-before mentioned.
I claim originality in the method of producing a negative photographi
in relief so that by pressure I obtain a positive in metallic relief that can
be printed from to produce photographs at the ordinary printing press.
I do not claim anything in common with the process known as photo-
relievo, my process being the reverse of the one named above, inasmuch
as the relievo process is intaglio, used with a special ink to suit the
requirements of that process; but I claim the process of making surface
blocks by photography and pressure to be printed from by the ordinary
methods of printing.
To use the composition above mentioned I level a slab of glass and
place paper or any other support, with the back wetted, perfectly flat on
the glass, and pour a sufficient quantity of the compound solution on to
the paper, after which it is hung up to dry. When the sensitised com-
pound is dry it is then rolled and placed under the positive in the
photographic printing frame, or it is placed under a negative if for an
intaglio plate and submitted to the action of light; daylight is best; the
electric light will do; when sufficiently impressed, which is determined
by the strength of the light, it is taken from the frame and transferred to
a type metal plate, the plate being highly polished; any other soft metal
will do when the block is to be electrotyped. With the negative photo-
graph now on the plate it is placed in warm water, the water being
changed until the parts not acted upon by light are washed away; the
plate is now dried, and the design in relief upon the plate is now ready
to be engraved by pressure, which is performed as follows:-If the plate
is inked at this stage with the roller it will deliver a negative print, the
lights and shadows are reversed, the whites print black and the blacks
white; the plate is therefore put between two highly polished steel
plates and placed upon the bed of the hydraulic press and submitted to

page_text: very great pressure; the type metal plate is now as smooth as the
steel plates between which it was pressed, consequently the parts of the
design that were in relief are now sunk and form the lights of the print;
the smooth parts facing the steel plate being the design to be printed
from in relief, the photograph is washed out of the plate that has been
pressed and the plate trimmed and mounted on a block in the usual
way; it is now ready for the press to be printed from in the way usually
adopted for printing woodcuts excepting the difference that a photo-
graph is used for the overlay instead of one cut by hand as for wood-
cuts. The photograph for the overlay is similar to the one used to
engrave the plate in respect to relief, but it must be printed from a
negative, care being taken that the negative is the exact size of the block
required, and the print is transferred to paper and adjusted to the tympan
of the press as is usual with ordinary overlays. By this arrangement it
will be seen that the photographic overlay will register the photo-
graphic relief block, and according to the gradations of the photograph
on the tympan of the press will be regulated the amount of ink delivered
to the print.
I also claim as original the method of engraving plates by photography
and pressure as described above, by the negative photograph in relief,
of all or any subjects that can be copied for the purposes of reproduction,
such as engravings, drawings, pen sketches, water color and other
drawings, reprints of books, and all objects or subjects that can be
photographed and engraved by the above mentioned process, as likewise
the production of designs in silver and gold from printed matter.
I now proceed in the description of the method by which plates can
be reproduced from printed matter, and which I claim to be original.
A negative is taken as denso as possible from the subject required in
block, and a transparent positive from that negative likewise as dense as
it possibly can be made by the ordinary means known to photographers;
the positive is then used as in the method described for nature photo-
graphs on a composition made of similar ingredients, or the same as used
for nature will do, the treatment is the same up to the pressure in the
hydraulic press; after the design is forced into the plate the boldest
parts of the work are treated with a solution of bichromate of potash and
allowed to dry, after which those parts that were so treated are coated
with strong gelatine and silex and dried in a warm place in the light;
the heat and light render those parts that were touched with the

page_text: bichromate insoluble, and after washing away the upper part of the
gelatine the whole is dried and again submitted to the press between
the steel plates, causing those parts to be deeper where the gelatine has
been applied; sulphate of iron, alum, or any powerful astringent can be
used instead of the bichromate solution, or anything that will render
gelatine insoluble. The plate is now washed in water containing an
alkali for the purpose of removing the photograph, after which it is
coated with zinc by electro-deposition in the usual way of depositing
that metal; the plate is now inked up with a hard smooth roller, taking
care that the lights are free from ink, it is then treated with the solution
of nut galls, phosphoric acid, and gum, used by zincographic printers.
The plate is used in either the press called the typo litho, the litho
machine, or when mounted in the type press without the lights being
cleared by cutting; or if the work is required to print at machine with
letterpress the largest of the lights are cleared in the type metal or lead
previous to electrotyping when that is required.
The advantages gained by this method of preparing blocks or plates
are, first, the rapid method by which the plates are made, the simplicity,
case, and certainty of production; and, next, the large number of photo-
graphs that can be printed at one operation.
In witness whereof, I, the said Robert Henclade Courtenay, have
hereunto set my hand and seal, this Twenty-sixth day of March,
in the year of our Lord One thousand eight hundred and seventy-
three.
25
· ROBERT HENELADE COURTENAY. (L.S.)