IMPROVEMENTS IN TYPOGRAPHIC ETCHING AND ENGRAVING, AND IN APPARATUS EMPLOYED THEREIN."
Year: 1872

page_text: LETTERS PATENT to Alfred Dawson and Henry Thomas Dawson, both
of The Cedars, Chiswick, in the County of Middlesex, for the In-
vention of "IMPROVEMENTS IN TYPOGRAPHIC ETCHING AND ENGRAVING, AND
IN APPARATUS EMPLOYED THEREIN."
PROVISIONAL SPECIFICATION left by the said Alfred Dawson and
Henry Thomas Dawson at the Office of the Commissioners of
Patents, with their Petition, on the 29th May 1872.
We, ALFRED DAWSON and HENRY THOMAS DAWSON, both of The
Cedars, Chiswick, in the County of Middlesex, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN TYPOGRAPHIC ETCHING
AND ENGRAVING, AND IN APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention has for it object improvements in typographic etching
and engraving, and in apparatus employed therein.
We proceed as follows:-We take a metal plate, and after cleaning it
we darken and abrade or color the whole surface. This we prefer to do
by means of a solution of a metallic salt which acts on the metal plate

page_text: so as to both to remove the polish and darken the surface. We heat these
plates and cover them with an opaque, white, or light colored ground
by means of a heated comb-like tool, and while the plate stands on a
levelling frame we let the ground set firm. We use a ground for the
above purpose which is prepared from solid paraffine by grinding or
mixing with it any white or opaque color.
We use
The drawing is now made upon the plate by means of etching points,
and if repairs or alterations are needed they can be made by means of a
heated tool. We then apply heat in such a manner as to fuse the entire
surface of the unremoved ground, after which we build up the larger
white spaces with solid paraffine or other fusible substance.
for this purpose an instrument like a mathematical pen and containing
the melted paraffine or other matter, and with this hot tool we pass over
the parts which it is desired to build up. We repeat these operations as
often as we find it necessary, and when the building up is completed the
ground is again fused to unite all the parts and additions into uniform
masses, and give them a shape the converse of which is best able to
resist the wear and pressure of printing. We then electrotype the
mould or plate. We also apply a composition of soap all over the
moulds or plates, so as to prevent the adhesion of the electrotypes to
their metallic portions, as well as to facilitate the application of plumbago
or any other electro conductor to the surface of the plates or moulds.
In the darkening and abrading. or coloring of the plate as herein
practised, we not only get the advantage of seeing the actual subject
drawn in its natural effect, but we get the more complete adhesion of the
ground. The drawing being (without any further transfer or operation)
the foundation of a mould, the perfection of the work tells up afterwards
in all its integrity, and there is no need for reversion, the opaque, white,
or colored matter being ground into the grounding material the effect of
it remains however thin or small are the particles of ground left on the
plate. All parts of the drawing being worked over and the blackest
parts being most worked upon, the small irregularities of surface which
such work produce all print in the press, and this gives a great fulness
and meaning to the deepest shadows, none of which advantages can be
obtained unless the printing face is an exact reproduction of a surface
which has been entirely produced by the drawing or etching point. The
lines being produced by the point and not afterwards altered have great
smoothness and freedom from granulation or any other roughness.

page_text: When a fine point is used great refinement of the work is obtained, so
that the softest possible greys may be faithfully printed in immediate
contrast with the strongest work. The resisting form produced by the
electrotype being derived from surfaces which have all been in a melted
state is very perfect. The process is economical and rapid. Alterations
can be effected at any stage, either in and during the first drawing, or
after the finishing of the mould, or during such finishing, or after an
electrotype has been removed from it, in which case a new electrotype
may be taken embodying the said alterations.
The Invention can be applied to many purposes in which engraving
is expensive, or difficult, or imperfect, or slow, whether in art or
manufacture.
When ruling in lines and shades there is a disadvantage in the use of
lines which are all straight or all alike in form, and we make use of
means which cause a variety in the form of the lines, which variety is
produced by hollowing out of the surface of a round ruler, which rule
guides the tool as it draws the line%; we form around the surface of the
ruler hollows small in depth, and equal in width to the length of the
waves desired in the lines ruled by it. These hollows do not proceed in
any regular manner round the ruler, but deviate and vary in their
directions, sometimes crossing each other, and at other times bending up
or down the line of the axis of the ruler. Now any series of lines ruled
with this ruler will have a pleasing effect through their variety of form,
and will not repeat themselves in a less space than the circumference of
the ruler.
We may also further vary the line by using a compound of two such
rulers, and we may also make a regular and symmetrical pattern on the
surface of the said ruler, when a regular and symmetrical pattern will be
seen in the lines produced by using it as a guide to the tool or engraving
point or nen
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Dawson and Henry Thomas Dawson in the
Great Seal Patent Office on the 29th November 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ALFRED
5 DAWSON and HENRY THOMAS DAWSON, both of The Cedars, Chiswick, in
the County of Middlesex, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of May, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors give
and grant unto us, the said Alfred Dawson and Henry Thomas Dawson,
Her special license that we, the said Alfred Dawson and Henry Thomas
Dawson, our executors, administrators, and assigns, or such others as we,
the said Alfred Dawson and Henry Thomas Dawson, our 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 "IMPROVEMENTS IN
TYPOGRAPHIC ETCHING AND ENGRAVING, AND IN APPARATUS EMPLOYED THEREIN,'
upon the condition (amongst others) that we, the said Alfred Dawson
and Henry Thomas Dawson, our executors or administrators, by an
instrument in writing under our or their hands and seals, or under the
hand and seal of one of us or them, 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 we, the said Alfred Dawson and Henry Thomas
Dawson, 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 :-
This Invention has for its object improvements in typographic etching
and engraving, and in apparatus employed therein.
The Invention is designed to produce surface printing blocks in which
the printing parts are in exact facsimile of the lines and marks made
by the artist whilst drawing the design, and in which also there are deep
curved hollows between the raised lines and marks which the paper in
printing cannot enter, and which hollow spaces are so formed as to
leave the lines so completely and perfectly buttressed up that no amount
of printing strain can crush or batter them down. In securing these
ends we proceed as follows:-We take a metal plate, by preference
brass, and after cleaning it we darken and abrade or color the whole

page_text: surface, this we prefer to do by means of a solution of a metallic salt,
which acts on the metal plate so as both to remove the polish and
darken the surface. In practice we use a weak solution of nitrate of
silver, containing say twenty grains to the pint of water.
The plate
which should be quite smooth is washed and rubbed clean with a piece of
pumice stone; whilst still wet it is placed upon a level grating and the
silver solution poured upon it. It is distributed and moved over the
plate with a soft brush until the surface has become dark all over, more
solution being poured on to the plate if the first quantity is found to be
insufficient. A few minutes at the most is sufficient to complete this
operation. The plate is then washed with water and dried by warming
it over a flame. When the plate is sufficiently warm we cover it with
an opaque white or light colored ground. The plate is touched with the
end of a thin cake of the grounding composition, which is rapidly moved
from place to place on the plate so as to leave a number of melted
streaks distributed pretty regularly all over the plate. The ground is
then spread by means of a warm or moderately hot rake-like tool,
consisting of a short rectangular brass bar, say two or three inches long,
with a wire or stem fixed at right angles to it and set in a handle.
This tool is so applied to the plate as to touch it along one of its edges,
and in this edge of the tool a number of V-formed notches are filed at
about a tenth of an inch apart so as to leave between them blunt
pointed teeth between which the melted composition is able to flow
freely. This tool spreads the ground evenly when it is drawn to and fro
over the surface of the plate. The ground is afterwards caused to flow
slightly over the plate by inclining it to and fro, which removes any
marks left by the teeth of the spreading tool, the plate is then placed
upon a level support, and in a short time the ground sets firm. The
thickness of the ground should be about one-eightieth of an inch more
or less. We use a ground composition for the above purpose which
is prepared from solid paraffin by grinding or mixing with it white
or opaque color. We employ for this purpose the best paraffin and
we melt it and grind the pigment with it. The best pigment for the
purpose we believe to be tungstate of lead, and this we grind with the
paraffin in the proportion of three parts by weight of paraffin to about
one of pigment. Or if preferred a tinted ground may be used, or even a
black ground, but less conveniently.

page_text: neated tool.
In drawing we use several tools, some broad for clean cutting like
chisels or turning tools, others have a fine point cut into several facets
for neatly turning the shavings away from the work in two or more 5
directions, according to the motion the point receives; the shavings are
removed by means of a badger hair brush. Other tools again are con-
structed for stamping or impressing the ground, common type being
frequently thus used.
The points for cutting the ground are used when the plate is cold, but 1
when type or type like tools are used the plate should be made warm
to the temperature of 100° to 110° Fahrenheit by holding it over a flame,
or by laying it upon a plate with warm water beneath, taking care not
to melt the composition.
We repair parts which are misdrawn by means of a small tool or wire 1
which is heated to the vapourising point of the paraffin (which adheres
to it) in a smokeless flame and applied to the plate so as to melt the
ground and cause it to flow over the false lines.
If a large surface requires to be thus mended little pieces of the
ground composition may be laid on the place and melted by means of 2
the repairing tool; a slight warmth in the plate is advantageous.
Sometimes we purposely cut away the ground, and afterwards use a
similar tool, but with a divided point like a mathematical pen for con-
taining a little melted ground, with which we then draw on the bare
or nearly bare part of the plate, and lines and marks so made appear 2
white in the print. In this way we are able to lay on lights and
produce an effect much admired by artists and draughtsmen.
Whenever the effect of a tint is to be produced we rule upon the
ground a number of fine equidistant lines, but when ruling shades
with lines there is a disadvantage in the use of lines which are all a
straight or all alike in form, and we make use of means which cause
a variety in the form of the lines, which variety is produced by hollowing
out the surface of a round ruler, which rule guides the tool as it draws
the line.
The machine we construct for the purpose consists of a frame mounted a
two wheels one at either end These wheels are fixed on an axle.

page_text: and can be turned by means of a screw upon a vertical axis and gearing
with worm teeth on the periphery of one of the wheels. There is a fine
ratchet wheel fixed upon the upright axis into the teeth of which a pawl
or driver works. The pawl or driver is carried by a lever handle which
can turn freely upon the upright axis, and which is moved to and fro
between adjustable stops to propel the machine short and regular
distances forward. The machine is also supported by a roller extending
along its front. This roller is most easily made of a tube closed at the
ends where are the pivots which connect it with the frame of the
machine, and the surface of the roller is battered or filed all over in
order to give the required irregularities or varying waves to the lines.
The wheels of the machine and also the roller at its ends run upon
raised fillets fixed upon the table on which the machine is used. The
plate to be ruled is placed upon the table between the fillets, so that the
machine can pass over it freely without touching it.
The ruling is done by means of a steel point, such as is used at other
times in drawing upon the plate. The tool is held in the hand and
drawn along in contact with the roller and also with a straight edge
fixed to the frame of the machine on which the tool rests near its
upper end.
It will be seen that the rotation of the roller as the machine is moved
forward step by step causes each line to be slightly different in its
minute bends from the line next to it, and so the requisite variety is
given to the shade.
Supposing now that the design required has been drawn upon the
plate and the artistic work complete, it will on examination be found
that the grooves or spaces in the ground will vary much in sectional
form, and in some cases there will be an overhanging of the grounding
material and in other parts a burr or ridge of unremoved ground beside
the line. To remove these irregularities and to give an equal and
similar form to the sides of all the grooves or spaces in the ground is the
object of the next process, and it will always be found that if this is not
effected the printing block made from the plate will give way after a few
hundred impressions have been taken from it. We apply heat in such a
manner as to fuse the entire surface of the unremoved ground, and so we
remove all these irregularities and obtain the forms required. The form
of fusion is always convex and therefore always causes small arches in
the printing block, and thus forms of great strength are given to the

page_text: printing parts. We effect this fusion by as it were brushing over the
surface of the plate with a gas flame. The burner used is a plain
perforation in the end of a closed metal tube attached to an india-rubber
gas pipe. The plate is laid on the hand so that the degree of warmth
can be appreciated and the flame is brushed to and fro many times over
it whilst the plate is slightly warm, and until it is seen that the surface
has changed its form. If this operation be carefully performed there is
no fear of the ground running over the lines. We then build up the
interspaces between the lines by applying a further quantity of paraffin
by means of a heated tool. This tool is made on a capillary principle so
that it will hold the melted paraffin as a pen does ink and discharge it
when its point is brought in contact with the work. We use a tool
composed of a narrow coil of stout copper wire, through which pass two
fine steel wires side by side to form a hard point, and other wires or
wedges for fastening the steel wires in the tool as well as to form a
number of capillary channels to hold and conduct the melted paraffin in
the manner of a wick.
The material we use is paraffin of a lower quality and melting at a
lower temperature than that for the ground and it need contain no
pigment. It is made up for use into small sticks with which the hot
tool is touched from time to time. Every particle of ground remaining
on the plate exceeding a few hundredths of an inch in length and width
is touched with the building up tool and a small quantity of melted
paraffin deposited upon it.
Where the work is fine care should be taken that the building up tool:
is not too full or the paraffin may run out and injure the drawing. This
having been done in order more perfectly to unite the paraffin thus laid
on with the ground beneath, and also to cause it to run up to the edges of
the lines and take forms of fusion, the plate is again brushed over with
the flame in the manner already described. This building up process is a
repeated once or twice until the open parts of the drawing have been
built up to a considerable height.
The plate having been thus completed we lather it with yellow soap
applied with a badger hair brush, and we then brush on to it with a
similar brush water which is rendered sour by the addition of muriatic
acid. This treatment causes a thin film of grease to be deposited on the
surface of the ground. In this state when dry we send the plate to the

page_text: electrotyper who first blackleads the surface with a soft brush, then
places it in his copper bath and starts the current immediately, having
first taken the usual precautions to expel air from the hollows. The
copper plate produced is mounted in the usual way for printing. The
drawing being by. this
process (without any transfer or destructive
operation) made the foundation of a mould, the perfection of the work
tells up afterwards in all its integrity. The opaque matter being ground
into the grounding material the effect of it remains however thin or
small are the particles of ground left on the plate.
All parts of the drawing being worked over and the blackest parts
being most worked upon, the small irregularities of surface which such
work produces all print in the press, and this gives a great fullness and
meaning to the deepest shadows, none of which advantages can be
obtained unless the printing face is an exact reproduction of a surface
which has been entirely produced by the drawing or etching point. The
lines being produced by the point and not afterwards altered have great
smoothness and freedom from granulation or any other roughness.
When a fine point is used great refinement of the work is obtained, so
that the softest possible greys may be faithfully printed in immediate
contrast with the strongest work.
Alterations can be made on the plate after an electrotype has been
removed from it, in which case a new electrotype may be taken
embodying the said alterations.
The Invention can be applied to many purposes in which engraving
is expensive or difficult, or imperfect, or slow, whether in art or
manufacture.
Having thus described the nature of our said Invention, and the
manner of performing the same, we would have it understood that we
claim, the production of surface printing blocks, substantially as
described.
We also claim in the production of surface printing blocks the use of
a paraffin ground, substantially as described.
We also claim the method of giving suitable resisting shapes to the
lines and grooves cut in the ground in forming the design, by fusing the
surface of the ground and by building upon it, substantially as described.

page_text: We also claim, the apparatus for ruling waved tints, substantially as
described.
In witness whereof, we, the said Alfred Dawson and Henry Thomas
Dawson, have hereunto set our hands and seals, this Twentieth
day of November, in the year of our Lord One thousand eight
hundred and seventy-two.