IMPROVED PROCESS FOR ENGRAVING METALLIC SURFACES EITHER IN RELIEF OR SUNK LINES, APPLICABLE TO COPPER-PLATE PRESSES OR TO ORDINARY PRINTING PRESSES
Year: 1860

page_text: LETTERS PATENT to Pierre Edelestan Stanislas Dulos, of No. 60,
Boulevart de Strasbourg, Paris, Metallic Plates Engraver, for the
Invention of "IMPROVED PROCESS FOR ENGRAVING METALLIC SURFACES
EITHER IN RELIEF OR SUNK LINES, APPLICABLE TO COPPER-PLATE PRESSES OR TO
ORDINARY PRINTING PRESSES."
Scaled the 14th August 1860, and dated the 18th February 1860.,
PROVISIONAL SPECIFICATION left by the said Pierre Edelestan Stanislas
Dulos, at the Office of the Commissioners of Patents, with his Petition;
on the 18th February 1860.
I, PIERRE EDELESTAN STANISLAS DULOS, of No. 60, Boulevart de Strasbourg,
Paris, Metallic Plates Engraver, do hereby declare the nature of the said
Invention for "IMPROVED PROCESS FOR ENGRAVING METALLIC SURFACES EITHER IN
RELIEF OR SUNK LINES, APPLICABLE TO COPPER-PLATE PRESSES OR TO ORDINARY
PRINTING PRESSES," to be as follows:-
This improved engraving process is founded on the fact that if mercury is
gently poured over a levelled silver surface, on which lines have been previously
drawn with varnish, the mercury will rise on both sides of the lines forming
convex surfaces or meniscus, but the varnish lines remain uncovered. I use
this property for obtaining engravings by taking a silver or silvered copper-
plate properly prepared, on the surface of which any drawing is either by
[Price 8d.]

page_text: transfer or otherwise is made; any of the usual transfer processes may be used
for that purpose. If the drawing is made directly on the plate, for instance
with a lithographic pencil, a very thin stratum of either copper or iron is then
deposited on the surface by means of a galvanic battery which metallic deposit
will only take place on the parts not marked with the pencil and these pencil
marks are then removed with turpentine. Now on this plate the white parts
of the drawing are covered by a copper or iron stratum, whilst the dark parts
or marks of the pencil are in uncovered silver, if mercury is now poured over
the plate it will adhere only to the silver, and by gently brushing off the super-
fluous mercury the previously made pencil drawing is got in lines standing in
relief. A cast is next taken from this plate with plaster, wax, or other suitable
material for obtaining a plate for printing in a copper-plate press, which is
done by taking an electrotype from the cast.
Another method which does away with the cast is by using a metal or alloy.
fusible at a low temperature, such as for instance as Darcet's fusible alloy to
which a small quantity of mercury should be added; when melted this metal
behaves just as the mercury does, and when cold is firm enough to print from.
For obtaining a relief line printing plate a thin stratum of either iron or
copper is first deposited over the silvered plate and the drawing is made on
this stratum, the iron or copper not protected by the pencil lines is then re-
moved, either by means of a galvanic battery or with acids, and the plate is
treated by the same process as previously described. The raised lines of the
metallic plate intended to be printed are then those of the drawing itself whilst
the sunk lines are represented by the mercury, or better still by the fusible
metal employed.
By this process a drawing made upon a silvered plate may be transformed
into a relief or into an intaglio plate so as to be printed in the first instance by
n typographic, or in the second instance by a copper-plate press.
A lithographic or old copper-plate print or a manuscript may be transformed
into a relief or into an intaglio plate by means of the usual transfer processes.
A photographic plate may thus be converted into a metallic one for
the purpose of printing it, either as a copper-plate or by means of a typo-
graphical press.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Pierre Edelestan Stanislas Dulos in the Great Seal Patent
Office on the 14th August 1860.
-
TO ALL TO WHOM THESE PRESENTS SHALL COME. I, PIERRE
EDELESTAN STANISLAS DULOs, of No. 60, Boulevart de Strasbourg, Paris,
Metallic Plates Engraver, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Iler Letters
Patent, bearing date the Eighteenth day of February, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Pierre Edelestan Stanislas Dulos, Her special licence that I, the said
Pierre Edelestan Stanislas Dulos, my executors, administrators, and assigns,
or such others as 1, the said Pierre Edelestan Stanislas Dulos, 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 ex-
pressed, should and lawfully might make, usc, exercise, and vend, within
the United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man an Invention for "IMPROVED PROCESS FOR ENGRAVING METALLIC
SURFACES EITHER IN RELIEF OR SUNK LINES APPLICABLE TO COPPER-PLATE PRESSES
OR TO ORDINARY PRINTING PRESSES," upon the condition (amongst others) that
1, the said Pierre Edelestan Stanislas Dulos, 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 Pierre Edelestan Stanislas Dulos, 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, that is to say:-
My engraving process is founded on the fact, that if mercury is carefully
poured over a level smooth silver plate on which lines were previously drawn
with varnish, two convex meniscus are formed on both sides of the said lines,
and the mercury rises above the silver surface. The same effect is produced
upon a ground glass plate, by drawing on the surface lines, with some greasy
substance and pouring water over this surface. It may be admitted generally,
that any liquid substance moistening a surface in which lines have been drawn
with a substance incapable of being wetted by it, will act the same as mercury

page_text: upon silver or water upon glass. Accordingly I take a silver plate, or a
silvered copper plate, upon the surface of which, I either draw; transport or
decalque" any sketch either landscape, or any other subject (any process
used for transporting or counterdrawing may be employed).
In order to have it better understood, I will first suppose that the subject
is directly drawn on the plate with an oily substance, such as a lithographic
pencil. I then deposit a very thin stratum either of copper or iron by
electrotyping; suppose we deposit iron; it is evident that this metal will
be deposited only on the places that have not been marked with the pencil
marks are washed off with turpentine, the white parts of the drawing are
represented by an iron stratum, and the pencil lines by the silver, now if
mercury is poured over the surface, it is evident, that the mercury will stick
only to the silver, and if the surplus covering the iron stratum, is brushed
off with a very smooth brush, relief. lines will be obtained, formed by the
mercury on those places where the pencil lines had previously been drawn.
There now remains to take a cast of it in order to get a plate with engraved
lines fit for printing under a copper-plate press, in which plate the hollow lines
will be represented by the relief ones of the mercury; this cast could not be
very well taken but with plaster, wax, or any other suitable soft substance
which would be two soft to print from, now if instead of mercury we use
another suitable metal or alloy, melting at a lower temperature, such as either
"Darcet's" metal to which a small quantity of mercury should be added or an
amalgam. When melted this metal will act just like mercury; however it is
preferable to use an amalgam either of copper or silver, such amalgams when
triturated, will flow almost like mercury alone, and after remaining at rest for
one or two hours, they will become as hard as stone. The raised lines being
thus produced over the pencil marks, the drawing is transformed into a mould
of which a copper cast may be taken by electrotype, this copper cast is a good
copper-plate fit for printing, in which, the engraved lines correspond to the
raised lines of the amalgamated metal. A great many printing plates can be
obtained from the same mould. Now if a surface printing plate is required a
stratum of iron is deposited as before described over the silver, the pencil
marks are washed off with turpentine, and some mercury being spread is
rubbed over the plate where it sticks only to the silver, a spreading roller
covered with copal varnish is then rolled over the surface of the plate, the var-
nish sticking only on the places where there are no marks of mercury. The
mercury is then volatilized and a thin stratum of copper is deposited by electro-
type upon the unvarnished parts of the plate, that is to say, in the places
where the pencil marks had been, the varnish coating is washed off with tur-

page_text: pentine and the stratum of iron that is under is removed by diluted sulphuric
or other suitable acid. the pencil lines of the drawing are then represented on
the plate by copper, and the white parts by silver. After the copper has been
submitted to an oxydizing process, the plate is heated with the amalgamated
metal as before described and a copper cast is taken as before, on which cast
the lines of the drawing are in relief, and the sunk lines are produced by the
stratum of the amalgamated metal.
A relief plate can also be obtained by depositing on the silvered plate before
making the drawing a very thin stratum either of copper or iron and making
the drawing or counterdrawing on this stratum, removing the copper or iron
from the places not drawn on by the pencil, either by means of a galvanic
battery or suitable acids, and afterwards the same operations as before
described are performed.
We might draw on the silvered plates with either black lead pencils, black
drawing pencils (crayon comti) or even with common ink, for I have observed
that if a plate thus drawn over is placed in a saturated solution of sulphate of
copper and put in communication with the negative pole of a very weak
battery for only a few minutes the copper is deposited with a great energy on
the pencil or ink lines and not at all on the silver.
Various applications of the aforesaid processes. obtain printing plates
engraved either in relief or sunk lines by the aforesaid processes, by counter-
drawing on a metallic plate, suitably prepared for that purpose, either a litho-
graphic or engraved print; this counterdrawing can be transformed into a
plate fit for printing either under the copper-plate press or the common
printing press; or I may make a drawing directly on a plate, and use this
drawing to get an engraved plate; for this purpose I take, for instance, a brass
plate and grain it with fine sand and a glass muller: then I deposit on its
surface a thin stratum of silver by means of a galvanic battery: one can draw
with great facility on this dead white surface either with lithographic ink or
pencil; the transferred drawing can be made either with black delineating
pencil "crayon comte." black lead pencil. or red ochre; benzine may be used
for washing off the wrong lines. great care being taken not to leave any trace
of the greasy substance. The engraving made by gravers may be imitated by
polishing perfectly a metallic plate. on which a thin layer of beeswax or gutta
percha is then spread by rubbing the surface with white lead and drawing on
the said layer either with an ivory or steel point, each line made with this point
uncovering the metallic surface appears black on a white ground. When the
drawing is completed the aforesaid operations can be pursued, and a printed
plate will be obtained either with relief or sunk lines.

page_text: I can also produce an aquatinta or "pointille" plate. For this purpose a
grain of aquatinta or "pointille" should previously be produced on a plate, a
cast of it being obtained by the action of a galvanic battery; the plate thus
obtained is then silvered and the drawing made on this silvered surface with a
lithographic pencil; white places can be made with a scraper. When the
cast has been obtained it produces pictures either aquatinta or "pointilli,"
giving black and white parts by printing; if the behaviour of the various
varnishes with mercury are borne in mind it will be easy to print by means of
a lithographic press a plate in which the lines of the drawing are represented
by copper, and the white parts by amalgamated silver; if the inking roller is
drawn over a plate prepared according to this principle the ink sticks only to
the copper whilst it is repulsed by the mercury which covers the silver, by
adding now and then some mercury to that on the silver the printing may be
carried on as well as with a lithographic stone; such plate might be even
used for printing under a common or typographical press, since the surface of
the plate does not require wetting.
Old prints or drawings can be reproduced by my process by transferring
them to plates prepared as aforesaid.
the plates I take advantage of the curious fact observed and related by Niepse
de St. Victor of iodine always depositing on the black parts in préférence to
the white places where none will deposit; on laying a print or drawing this
impregnated with iodine on a carefully polished silver plate. the iodine
covering the black parts of the print transforms the silver into iodode of silver
in the corresponding parts, whilst the silver remains unacted upon in all the
places corresponding to the white parts of the print. the plate thus treated
being placed in a saturated solution of sulphate of copper, and put in com-
munication with the negative pole of a galvanic battery, the copper deposits
itself only on the pure silver, provided, however, that the plate shall remain
but a short time in the bath, the iodine of silver being then washed away with
a solution of hyposulphite of soda; the white parts of the engraving or
drawing are then represented by copper and the black parts by the silver itself.
The surface of this plate is then in the required conditions to obtain an
engraved plate fit for printing, which is obtained by the processes before
described.
To transfer such prints or drawings to
I can also reproduce either a drawing or an engraving by the photographic
process by using the said drawing or engraving as a "cliche" by means of the
light working through the transparency of the paper, or else I take a negative
proof of the said drawing or engraving with a camera obscura, and applying this
negative proof on a silvered copper-plate, over the surface of which would be

page_text: previously spread a layer either of bitumen of Judea dissolved in benzine or of
bichromate of potash dissolved in some organic substance, such as gelatine
as stated by Talbot, the whole being exposed to the action of light during a longer
or shorter time, then dissolving the layer of bitumen of Judea or bichromate of
potash in the places where the light has not exerted any action cn it; thus I
obtain a surface on which the silver appears in the metallic state in the places
corresponding to the black parts of the photographic proof, and the white parts
as represented by the layer of bitumen or bichromate of potash. If now, copper
were to be deposited over the surface of this plate by galvanic process, this
copper will deposit itself only on the pure silver, then by taking off the bitumen
of Judea or bichromate of potash which might remain on. the plate is in the
required condition for making an engraved plate by the above described
processes. An engraved plate can be obtained in the same way by using any
negative photographic proof.
Whatever may be the modifications which experience or practice may show
to be desirable one may perceive that all of them have for their origin and
starting point the capillary phenomena which I have observed as related in
the beginning, and the properties and action of some substances or agents
acting upon each other for producing some effects which I take advantage of
for obtaining the above results.
Briefly I claim my Invention the various processes herein-before
described for engraving in relief or in sunk lines metallic plates intended
for printing either by means of the copper-plate or by the common typographic
process, claiming the exclusive right to apply either of the said engraving
processes according to the circumstance and nature of the subjects to be
reproduced either by transferring or making a "decalque" of either an
engraving, or lithograph, or an ordinary drawing obtained by ordinary
processes or by the photographic process related above.
In witness whereof, I, the said Pierre Edelestan Stanislas Dulos, have
hereunto set my hand and seal, this Thirteenth day of August, in the
year of our Lord One thousand eight hundred and sixty.
Signed and sealed in the presence of
L. D'AUBREVILLE, C.E.
P. E. S. DULOS. (L.S.)