A. NEW PROCESS FOR THE REPRODUCTION OF DESIGNS APPLICABLE TO THE ILLUSTRATION OF BOOKS AND THE LIKE "
Year: 1882

page_text: LETTERS PATENT to William Patrick Bruce of Kinleith Currie, Midlothian
for an Invention of "A. NEW PROCESS FOR THE REPRODUCTION OF DESIGNS
APPLICABLE TO THE ILLUSTRATION OF BOOKS AND THE LIKE
"
PROVISIONAL SPECIFICATION left by the said William Patrick Bruce at
the Office of the Commissioners of Patents on the 13th July 1882.
WILLIAM PATRICK BRUCE of. Kinleith Currie, Midlothian "A NEW PROCESS
FOR THE REPRODUCTION OF DESIGNS APPLICABLE TO THE ILLUSTRATION OF BOOKS
AND THE LIKE
"
This Invention has for its object a new process for the reproduction of designs
applicable to the illustration of books and the like.
In this process the artist draws with the etching needle on a grounded metal
plate the lines or spaces which are to be light in the proof. These are then
excavated by means of a chemical mordant and the plate is printed like
wood cut,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Patrick Bruce in the Great Seal Patent Office on the
11th January 1883.
WILLIAM PATRICK BRUCE of Kinleith Currie Midlothian
"A NEW PROCESS
FOR THE REPRODUCTION OF DESIGNS APPLICABLE TO THE ILLUSTRATION OF BOOKS
AND THE LIKE'
"
This Invention has for its object a new process for the reproduction of designs
applicable to the illustration of books and the like.
or
In carrying out this Invention I first obtain or prepare a plate of copper, zinc
or other suitable metal or mixture of metals its surface being polished granulated
or roughened as required. The plate is then to be coated with etching ground
which may be done in any of the ways ordinarily employed by etchers in preparing
a plate for etching. The design is then to be produced by removing portions of
the ground from the surface of the plate by means of an etching needle or other
suitable instrument (one instrument I find very useful is a flat "brush"
"comb" the bristles of which are formed by a number of needles placed side by
side in a fold of paper between two small metal plates and clamped in an ordinary
crayon holder). The lines or spaces thus exposed it is to be understood will remain
light in the proof and those parts on which the ground remains undisturbed are
to print dark-If dark lines or spaces are required on a light ground (which has
been produced by the entire or partial removal of the etching ground from a part
of the plate with the etching needle or tool) such lines or spaces may be drawn
with "stopping out varnish" before the plate is exposed to the mordant. The
plate is then immersed in a liquid chemical-mordant the back of the plate and
parts not intended to be bitten being protected from its action. The mordant I
generally employ is nitric acid diluted with water in varying proportions according
to the nature of the metal used. Different degrees of depth may be given to the
light lines or spaces by a varying length of exposure to the mordant and "stopping
out as understood by etchers may be employed but of course with an opposite
purpose and result, those passages in the design which are intended to appear
dark being stopped out after a short exposure. When the plate is taken out of the
mordant it may be found to require touching up which may be done with a graver
and in the broad lights, if necessary, the depth may be increased with a gouge, or
the plate may be regrounded and partly or wholly rebitten or more work may be
added with the etching needle or tool-The plate is then mounted on wood or
other suitable material to the proper thickness for a typographic press when it is
ready to be printed as a relief block.
"
It may be briefly stated that any process applicable to ordinary etching is also
applicable to this, the difference being that what produces dark on a light ground
in ordinary etching produces light on a dark ground in this process and that in
this process the plate is to be printed like a woodcut.
Having thus described the nature of my said Invention and and the manner of
performing the same I would have it understood that I claim my process for the
reproduction of designs applicable to the illustration of books and the like such
process consisting in coating a metal plate with etching ground then producing a
design thereon by removing parts of such ground with an etching needle or tool
and with the aid if need be of lines drawn with varnish upon the parts of the
plate from which the ground has been removed by the tool, then biting the plate

page_text: 5
and dissolving away the exposed metal and finally when the plate is properly
finished and mounted printing therefrom in a typographic printing press
substantially as herein described.
In witness whereof I the said William Patrick Bruce have hereunto
set my hand and seal this Tenth day of January in the year of our Lord
One thousand eight hundred and eighty three.