AN IMPROVED PROCESS FOR PRODUCING PHOTOGRAPHIC PICTURES OR DESIGNS ON THE SURFACE OF STONE OR METALS SO THAT IMPRESSIONS MAY BE TAKEN THEREFROM BY THE PROCESS OF LITHOGRAPHIC PRINTING
Year: 1858

page_text: ETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for the
Invention of "AN IMPROVED PROCESS FOR PRODUCING PHOTOGRAPHIC PICTURES
OR DESIGNS ON THE SURFACE OF STONE OR METALS SO THAT IMPRESSIONS MAY
BE TAKEN THEREFROM BY THE PROCESS OF LITHOGRAPHIC PRINTING."-A com-
munication from A. Cutting and Lodowick H. Bradford, of Boston,
Massachusetts, in the United States of America.
Sealed the 25th May 1858, and dated the 23rd February 1858.
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on the
23rd February 1858.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lanc,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED PROCESS FOR PRODUCING PHOTOGRAPHIC
PICTURES OR DESIGNS ON THE SURFACE OF STONE OR METALS SO THAT IMPRESSIONS
MAY BE TAKEN THEREFROM BY THE PROCESS OF LITHOGRAPHIC PRINTING," to be as
follows:
This Invention has for its object the production of a photographic picture
upon the surface of a lithographic stone or sheet of metal from which impres-
sions may be taken by the ordinary process of lithographic printing.
The Invention consists, firstly, in applying to the surface of a clean stone
¡Price 8d1

page_text: a solution of gum arabic, which lías been deprived of its power to unite closely
with the stone, or to adhere firmly to its surface until it has been subjected to
the subsequent processes. The gum solution must at the same time be
endowed with the capability of uniting with or adhering to the stone, as above
described, on exposure to light.
The Invention consists, secondly, in removing those portions of the gum
arabic mixture which have not been acted upon by the light, by means of a
solution of soap, which at the same time leaves upon the unlighted portions of
the picture an insoluble soap to form the groundwork from which the picture
is printed, as in the ordinary lithographic process. The surface of the stone
after being prepared either by polishing or graining is covered with a pre-
paration of coinposition consisting of a solution in water of gum arabic with
sugar and bichromate of potass; the sugar retards the immediate fixing of the
gum upon the stone, and the chromic salt causes it to become more firmly fixed
or much less soluble on exposure to the light. Other substances which will have
an analogous effect on the gum (such as molasses, acetic acid, &c.) may be
employed in place of the sugar; analogoussalts may also be employed in place
of or in addition to the chromic salt. The stone thus prepared is preserved in
the dark until required, and when the coating is dried it may be exposed in
the camera a suitable lengtli of time, to fix the gum upon those parts of the
picture where the lights are to appear, or it may be covered by a negative or
a print or picture to be reproduced. The stone is then waslied with a solution
of soap, which attacks the stone and removes the coating, and fixes itself (oran
insoluble soap formed by the mutual decomposition of the stone and the soap
employed) upon the surface in place of the coating removed. Where the
gummed surface has been entirely protected from the light the gum is easily
removed and the soap has free access to the stone, and the consequence is a
thorough union of the soap with its surface; where, on the contrary, the lights
were strong, the gum having been rendered much more insoluble, is protected
from the action of the soap, and is not affected by it.. The stone having been
thoroughly. washed with clean water. and dried now receives a coating of ink
from the roller, which, uniting with the soapalready deposited thereon, serves
to give additional body to the picture, and shortly after the stone is ready for
the printer.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
:
by the said William Edward Newton in the Great Seal Patent Office on
the 21st August 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of February, in the year of our Lord'
1858, in the twenty-first year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said William Edward Newton, Her
special license that I, the said William Edward Newton, my executors,
administrators, and assigns, or such others as I, the said William Edward
Newton, 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 of "AN IMPROVED PROCESS FOR PRO-
DUCING PHOTOGRAPHIC PICTURES OR DESIGNS ON THE SURFACE OF STONE OR METALS
SO THAT. IMPRESSIONS MAY BE TAKEN THERE FROM BY THE PROCESS OF LITHOGRAPHIC
PRINTING," being a communication from A. Cutting and Lodowick H. Bradford,
of Boston, Massachusetts, in the United States of America, upon the condition,
amongst others, that I, the said William Edward Newton, 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 months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said William Edward Newton, 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 fol-
lowing statement (that is to say):-
.:
This Invention has for its object the production of.a photographic picture
upon the surface of a lithographic stone, from which impressions may be
taken by the ordinary process of lithographic printing, by which I am enabled.
to greatly multiply the results of photography and to avoid the tedious and
expensive process of drawing upon the stone by hand as at present practised.
In the ordinary process of lithographic printing the surface of the stone after
the drawing is completed is washed or coated with a solution of gum arabic.

page_text: in acidulated water. The gum thus applied enters into a close union with,
the surface of ilie stone or adheres with great tenacity thereto, so that it
cannot readily be removed by washing, and thus protects it from absorbing
the ink employed in the printing process. In the process of photo-lithography
it is found, however, that the gum arabic adheres so closely to the stone as
not to be readily removed by washing from those portions not fixed by the
light. On this account, in the experiments heretofore made in photo-litho-
graphy it has been found impracticable to employ this gum, and a solution of
gelatine has been used in its stead. Stones thus prepared, however, yield but
few impressions, and are of comparatively small value in the arts. To remedy
this difficulty is the object of this Invention, which consists in the employment
of gum arabic which has been deprived of its power of intimate union with
the stone, at the same time that it is rendered capable of becoming fixed or
insoluble by the operation of light. When a stone treated with the above
prepared gum is subsequently submitted to the action of a solution of soap,
the unlighted portions of the gum are readily and expeditiously removed,
while the lighted portions are not injuriously affected thereby, at the same
time that the soap performs its well-known duty of forming theinsoluble soap
upon the stone to produce the body or printing surface. The stone, after
being prepared in a manner which will be more fully explained hereafter, has
the following solution applied to its surface:-Water, one quart; gum arabic,
4 oz.; sugar, 160 grains; bichromate potassa, 160 grains; the sugar retarding
the immediate fixing of the gum upon the stone, and the chromic salt causing
it to become more firmly fixed or much less soluble on exposure to the light..
The stone thus prepared is preserved in the dark until required, and when
the coating is dried it may be exposed in the camera a suitable length. of
time to fix the gum upon those parts of the picture where the lights are to
appear, or it may be covered by the print or picture to be reproduced and
exposed to the light.. After it is thus "lighted," the stone is washed with
a solution of soap, which attacks the stone, removing the coating and fixing
itself (or an insoluble soap formed by the mutual decomposition of the stone
and the soap employed) upon the surface in place of the coating removed..
Where the gummed surface has been entirely protected from the light the
gum is easily removed, and the soap has free access to the stone, and the
consequence is a thorough union of the soap with its surface; where, on
the contrary, the lights were strong, the gum having been rendered much
more insoluble, is protected from the action of the soap, and is not affected
by it; and at all intermediate points the effect of the soap upon the stone is
inversely proportionate to the extent to which the gum was fixed by the light.

page_text: The most delicate grades and tints of light and shade may thus be produced
upon the stone true to nature as the photographic picture itself. The stone
having been thoroughly washed with clean water and dried, now receives a
coating of ink from the roller, which, uniting with the soap already deposited
thereon, serves to give additional body to the picture, and shortly after the
stone is ready for the printer; the portions which have been protected by the
undissolved or "lighted" gum-when wet resisting the ink. Previous to
the commencement of the above-described process the stone is to be prepared,
and this preparation will vary according to the nature of the picture or subject
to, be produced. If it be a manuscript, a lithograph, line engraving, or any
plan or line drawing without gradations of shade or shadow, running the one
into the other, a polished surface may be employed: This will not answer,
however; so well for portraits, landscapes, and a great, variety of other
pictures in which the variations of shade blend the one into the other; in
such cases it becomes necessary to give the stone a roughened surface, or in
the language of the workman, the stone is "grained." Into such a surface
the chromated solution of gum sinks deeper, and is then removed more or
less according as it has been fixed by the light, and thus the required
variations of intensity and the gradations of shade and shadow are produced.
Where a polished stone is employed the chromated gum lies upon the surface,
and it is found that the variations of shade and shadow cannot be produced
with that nicety necessary to make a perfect graduated picture such as a
portrait that shall be easily printed.
In preparing the chromated solution the proportions of the ingredients
given above are by no means rigid, though they are those which we have
found to answer the purpose. The sugar we have found also may be replaced
by other substances, such as molasses, acetic acid, or various acetates not
decomposable by the bichromate of potassa. I do not, therefore, confine
myself to the exact proportions given above, nor even to the use of the exact
substances named when there are equivalents for them which may be used in
their stead without departing from the essence of this Invention. And in
place of removing the unlighted portions of the coating by means of the direct
application of soap, they may be washed off with water, acetic acid, or their
equivalents; oils, resins, or printing inks being applied after the stone has
been dried for the purpose of forming the required insoluble soap in the
stone; such process is the entire equivalent of the one above described,
although it is neither so expeditious nor so efficient. The quality of the soap
employed is not rigid, though those containing a proportion of resin will in
general give a better result. The strength of the saponaceous solution is not

page_text: material; lb. of soap to 6 quarts water has been found to answer the
purpose. Heretofore this process has been spoken of as applied to litho-
graphic stones, but there are other substances which may be employed in lieu
of the stone to which it may be applied, one of which is zinc, which has been
heretofore used by printers as a substitute for stone; in the use of this metal
an insoluble soap of zinc is formed instead of one of lime.
:
Having now set forth the nature of this Invention, and explained the
manner of carrying the same into effect, I wish it to be understood that under
the above recited Letters Patent I claim, the employment of gum arabic
deprived of its power of intimate union with the stone by means of sugar or
its equivalent, as set forth, and in combination with the above I claim the
use of soap, as set forth, for the purpose of readily removing the unlighted
portions of gum and of forming the printing surface, as described.
In witness whereof, I, the said William Edward Newton, have hereunto
set iny hand and seal, the Seventeenth day of August, in the year of
our Lord One thousand eight hundred and fifty-eight.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)