IMPROVEMENTS IN ENGRAVING UPON METAL, STONE, MARBLE, AND OTHER HARD SUBSTANCES
Year: 1879

page_text: LETTERS PATENT to Antoine Désiré L'Heureux, of Tolmers Square, Hampstead
Road, Middlesex, for the Invention of "IMPROVEMENTS IN ENGRAVING UPON
METAL, STONE, MARBLE, AND OTHER HARD SUBSTANCES."
PROVISIONAL SPECIFICATION left by the said Antoine Désiré L'Heureux
at the Office of the Commissioners of Patents on the 13th September 1879.
ANTOINE DÉSIRÉ L'HEUREUX, of Tolmers Square, Hampstead Road, Middlesex.
"IMPROVEMENTS IN ENGRAVING UPON METAL, STONE, MARBLE, AND OTHER HARD
SUBSTANCES."
This Invention relates to improvements in engraving a design either incised or
in relief, or doubly incised or in double relief, upon metal, stone, marble, and other
hard substances, whereby the same is effected with far greater facility and economy
than has hitherto been practicable at the same time that a more perfect result is
obtained. This I do by engraving the design either directly upon the surface of
the metal, stone, marble, or other hard substance (hereafter termed the plate) or
first covering, or partially covering such plate with a suitable film or coating, or by
means of a transfer, or of incrustation, as hereafter described.
The first part of my Invention relates to producing a design, either incised or in
relief, directly upon the surface of the plate. In order to carry out this part of my
Invention I first execute the design directly upon such surface either by means of
a transfer as presently described, or preferably by means of an ink, consisting of
sugar, common ink, and black lead mixed together in suitable proportions. I then
cover the parts which are to be protected from the acid with a suitable varnish,
after which I apply the acid when the design is bitten in.
Or I proceed as follows:-After having executed the design directly upon the
plate or tablet, as before mentioned, I cover the whole surface (with a suitable
resinous compound capable of dissolving in benzoline or other similar spirit, I then
by means of a roller made of india rubber or cloth, and moistened with gelatine, or
by means of a suitable dissolvent, disclose the design, after which the same is bitten
in with acid in the ordinary way.
Or after having disclosed the design I cover the same with a varnish of shellac
dissolved in methylated spirit. I then wash the surface covered with the resinous

page_text: varnish either with petroleum or benzoline, the result being that the parts protected
by the shellac varnish are left apparent while the varnish thereon remains
undissolved.
To produce a design in double relief I first partially cover the surface of the plate
to be engraved with a coating of pitch, I then partially cover such coating of pitch
with shellac varnish made as before described, taking care that a margin of any
convenient depth is left around both the coating of pitch and the coating of varnish.
The plate is then immersed in the acid which bites away the unprotected surface
thereof, leaving the pitch and varnish intact, and in order to remove the pitch the
plate is taken out of the acid and benzoline or petroleum is applied which removes
the pitch, after which the slab is immersed in the acid and bitten to the required
depth. The parts of the design which are protected by the shellac varnish are
those which stand out in the boldest relief and have the greatest depth..
To produce a doubly incised design I first draw the outline of the design in
pencil upon the plate, I then thicken such outline with an ink composed of lamp
black and pitch dissolved in benzoline or any suitable equivalent. I then cover the
parts to be protected from the acid with a suitable varnish, and immerse the plate
in the acid, which bites in such portions as are left unprotected by the varnish. I
then take the plate out of the acid and remove the ink with benzoline or petro-
leum, after which I re-immerse the plate in the acid which bites away the portion
previously covered with the ink to the requisite depth, and thus produces a design
doubly incised.
The second part of my Invention relates to producing a design upon a plate by first
covering the surface of the plate with a solution of starch or other suitable equivalent.
When dry, such solution forms a film upon which I etch the design, and then
paint over such etching with a suitable varnish such as shellac mixed with methy-
lated spirit. I then immerse the plate in the acid which dissolves the solution
remaining on those portions which are left unprotected and bites in the ground-
work.
Or I cover the surface of the plate to be engraved with a solution of crystallisable
sugar, after which I paint the same with black lead so as to neutralize the non-
crystallisable ink next mentioned. I then draw a design thereon with a
'non-crystallisable ink made of molasses or treacle, or any suitable equivalent,
dissolved in water, and when the ink has remained a sufficient time to soften the
solution of crystallisable sugar I brush over the design with a dabber and whiting,
after which I cover the parts disclosed by this operation with any suitable varnish
as mentioned in the first process, and apply the acid whereby all the remaining
crystallisable sugar is removed without injuring the design.
The third part of my Invention relates to producing a design either incised or in
relief by means of a transfer instead of drawing or etching the design as previously
described. To effect this I draw the design upon any suitable substance, such as
paper or cloth, with an ink made as previously described, or composed of gelatine
or starch, or other suitable material, which paper or cloth then becomes the transfer.
I then cover this transfer with a resinous solution, and disclose the design by means
of an india rubber or cloth roller moistened with gelatine, or by any other suitable
means, after, which I apply the transfer to the plate and take an impression by
means of heat or otherwise; I then apply such acid or acids as will naturally act
upon the transfer before acting upon the plate, and if practicable I "prick through"
the design previous to transferring it so as to facilitate the acid biting. When so
transferred it is obvious that the contrary impression. of the design is obtained
upon the plate. To obviate this, previous to laying the transfer upon the plate I
apply acid to such transfer until the design shews through the back thereof which
thus becomes the face of the transfer, I then cover such transfer with a resinous
varnish, after which I place such transfer upon the plate, and then immerse the
plate in the acid.
Or I transfer a design or engraving from one plate to another by covering the
engraved surface with a solution of pitch or caoutchouc, or gutta percha, and

page_text: placing upon
it a transfer sheet moistened with gelatine or sugar. By pressure the
pitch upon the plate adheres to the gelatine on the transfer, which is then removed
therefrom and laid down upon the plate to be engraved. I then moisten the back
of such transfer with water, which dissolves the gelatine and enables the paper to
be easily removed, leaving the pitch upon the plate. I then cover the parts to be
engraved with a solution of gelatine, and apply an additional coating of pitch so as
to ensure sufficient resistance to the acid when the plate is immersed therein in
order to bite in the design. Previously to applying such additional coating I warm
the plate in order to set the gelatine, and I also heat the plate to be engraved so as.
to cause the pitch upon the transfer to adhere thereto.
The fourth part of my Invention relates to producing a design by incrustation,
i.e., incrusted with a composition of different colors joined together and inserted to
the depth of any given incising. To effect this I first incise the design, after which
I fill it up by means of hot irons with a suitably colored composition of shellac. I
then surface off and cover such parts of the engraved surface as are to be protected
from the acid with a suitable oleagenous substance. I then apply the acid, and,'
when it has eaten its way to the base of the first incrustation, suspend the operation,
and in order to separate the colors fill up the groundwork of the design with a
suitably colored composition such as cement or varnish which does not require to
be liquified by heat, and when this filling up becomes dry I again surface off in the
ordinary manner.
In order to produce a design incrusted in various colors, similar to a painting, it
is only necessary to make a separate incising for each color.
To imitate mosaic work I proceed as follows:-I etch the design upon the plate,
to which, if absorbent, I apply oil in the incising so as to prevent the incrustation
being injured by damp. I then fill the incising with refined pitch and pulverised
marble of any required color, and run in the pitch by means of hot irons, after
which I surface off and thus obtain a result of colored marble in a black ground.
After the surfacing I wash away with petroleum or benzoline all the superficial
pitch, which I afterwards replace with suitable varnish or cement colored according
to requirements,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Antoine Désiré L'Heureux in the Great Seal Patent Office on the
13th March 1880.
ANTOINE DÉSIRÉ L'HEUREUX, of Tolmers Square, Hampstead Road, Middlesex.
"IMPROVEMENTS IN ENGRAVING UPON METAL, STONE, MARBLE, AND OTHER HARD
SUBSTANCES."
This Invention relates to improvements in engraving a design, either incised or
in relief, or doubly incised, or in double relief upon metal, stone, marble, and other
hard substances, whereby the same is effected with far greater facility and economy
than has hitherto been practicable, and at the same time that a more perfect result
is obtained. This I do by engraving the design either directly upon the surface of
the metal, stone, marble, or other hard substance (hereafter termed the plate), or
first covering or partially covering such plate with a suitable film or coating, or by
means of a transfer or of incrustation as hereafter described.
"
The first part of my Invention relates to producing a design either incised or in
relief directly upon the surface of the plate. In order to carry out this part of my
Invention I first execute the design directly upon such surface either by means of
a transfer as presently described or preferably by means of an ink consisting of
sugar, common ink, and black lead mixed together in suitable proportions; I some-
times prefer to add a little alum in order to increase the liquifaction. I then cover
the parts which are to be protected from the acid with a suitable varnish, after
which I apply the acid when the design is bitten in.
Or I proceed as follows:-After having executed the design directly upon the
plate or tablet as before mentioned I cover the whole surface with a suitable resinous
compound capable of dissolving in benzoline or other similar spirit; I then by means
of a roller made of india rubber or cloth, and moistened with gelatine, or by means
of a suitable dissolvent disclose the design, after which the same is bitten in with
acid in the ordinary way.
Or after having disclosed the design I cover the same with a varnish of shellac
dissolved in methylated spirit; I then wash the surface covered with the resinous
varnish either with petroleum or benzoline, the result being that the parts pro-
tected by the shellac varnish are left apparent while the varnish thereon remains
undissolved.
To produce a design in double relief I first partially cover the surface of the plate
to be engraved with a coating of pitch, I then partially cover such coating of pitch
with shellac varnish made as before described, taking care that a margin of any
convenient depth is left around both the coating of pitch and the coating of varnish.
The plate is then immersed in the acid which bites away the unprotected surface
thereof, leaving the pitch and varnish intact, and in order to remove the pitch the
plate is taken out of the acid and benzoline or petroleum is applied, which removes
the pitch, after which the slab is re-immersed in the acid and bitten to the required
depth. The parts of the design which are protected by the shellac varnish are those
which stand out in the boldest relief and have the greatest depth.
To produce a doubly incised design I first draw the outline of the design in pencil
upon the plate, I then thicken such outline with an ink composed of lamp black and
pitch dissolved in benzoline or any suitable equivalent, I then cover the parts to be
protected from the acid with a suitable varnish and immerse the plate in the acid
which bites in such portions as are left unprotected by the varnish, I then take the
plate out of the acid and remove the ink with benzoline or petroleum, after which
I re-immerse the plate in the acid which bites away the portion previously covered
with the ink to the requisite depth and thus produces a design doubly incised.
The second part of my Invention relates to producing a design upon a plate by
first covering the surface of the plate with a solution of starch or other suitable

page_text: equivalent. When dry such solution forms a film upon which I etch the design,
and then paint over such etching with a suitable varnish such as shellac mixed
with methylated spirit. I then immerse the plate in the acid which dissolves the
solution remaining on those portions which are left unprotected and bites in the
ground work.
Or I cover the surface of the plate to be engraved with a solution of crystal-
lisable sugar, after which I paint the same with black lead, so as to neutralize the
non-crystallisable ink next mentioned. I then draw a design thereon with a non-
crystallisable ink made of molasses or treacle or any suitable equivalent dissolved
in water, and when the ink has remained a sufficient time to soften the solution of
crystallisable sugar I brush over the design with a dabber and whiting, after which
I cover the parts disclosed by this operation with any suitable varnish, as mentioned
in the first process, and apply the acid whereby all the remaining crystallisable
sugar is removed without injuring the design.
The third part of my Invention relates to producing a design upon a plate either
incised or in relief by means of a transfer, instead of drawing or etching the design
as previously described. To effect this I draw the design upon any suitable
substance such as paper or cloth with an ink made as previously described, or
composed of gelatine or starch or other suitable material, which paper or cloth then
becomes the transfer. I then cover this transfer with a resinous solution and
disclose the design by means of an india rubber or cloth roller moistened with
gelatine or by any other suitable means, after which I apply the transfer to the
plate and take an impression by means of heat or otherwise. I then apply such
acid or acids as will naturally act upon the transfer before acting upon the plate,
and if practicable I " prick through", the design previous to transferring it so as to
facilitate the acid biting. When so transferred it is obvious that the contrary
impression of the design is obtained upon the plate. To obviate this, previous to
laying the transfer upon the plate, I apply acid to such transfer until the design
shews through the back thereof, which thus becomes the face of the transfer. I
then cover such transfer with a resinous varnish, after which I place such transfer
upon the plate and then immerse the plate in the acid.
Or I transfer a design or engraving from one plate to another by covering the
engraved surface with a solution of pitch or caoutchouc or gutta percha, and placing
upon it.a transfer, sheet moistened with gelatine or sugar. By pressure the pitch
upon the plate adheres to the gelatine on the transfer which is then removed there-
from and laid down upon the plate to be engraved. I then moisten the back of
such transfer with water which dissolves the gelatine and enables the paper to be
easily removed, leaving the pitch upon the plate. I then cover the parts to be
engraved with a solution of gelatine and apply an additional coating of pitch so as
to ensure sufficient resistance to the acid when the plate is immersed therein in
order to bite in the design. Previously to applying such additional coating I warm
the plate in order to set the gelatine, and I also heat the plate to be engraved so as
to cause the pitch upon the transfer to adhere thereto.
The fourth part of my Invention relates to producing a design by incrustation, i.e.,
incrusted with a composition of different colors joined together and inserted to the
depth of any given incising in the plate. To effect this I first incise the design,
after which I fill it up by means of hot irons with a suitably colored composition
of shellac, I then surface off and cover such parts of the engraved surface as are to
be protected from the acid with a suitable oleagenous substance. I then apply the
acid and when it has eaten its way to the base of the first incrustation suspend the
operation, and in order to separate the colors fill up the groundwork of the design
with a suitably colored composition, such as cement or varnish which does not
require to be liquified by heat, and when this filling up becomes dry I again
surface off in the ordinary manner.
In order to produce a design incrusted in various colors, similar to a painting, it
is only necessary to make a separate incising for each color.
To imitate mosaic work I proceed as follows:-I etch the design upon the plate,

page_text: to which if absorbent I apply oil in the incising so as to prevent the incrustation
being injured by damp; I then fill the incising with refined pitch and pulverised
marble of any required color and run in the pitch by means of hot irons, after
which I surface off, and thus obtain a result of colored marble in a black ground.
After the surfacing I wash away with petroleum or benzoline, all the superficial
pitch which I.afterwards replace with suitable varnish or cement colored according
to requirements.
Having thus particularly described the nature of my said Invention and the
manner of carrying the same into effect, I would have it understood that with
regard to the first part of my Invention I claim,
Firstly. The producing and fixing a design either incised or in relief directly
upon the surface of the plate by all, any, or either of the processes herein before set
forth and described for that purpose.
Secondly. The producing and fixing a design either in double relief or doubly
incised by either of the processes hereinbefore set forth and described for that
purpose.
With regard to the second part of my Invention I claim,-
The producing and fixing a design upon a plate, by first covering the surface
thereof with a suitable film, and then etching or drawing the design thereon, and
subsequently disclosing and fixing such design in the manner and by the means
herein before set forth and described for that purpose.
With regard to the third part of my Invention I claim,-
Firstly. The producing and fixing a design upon a plate either incised or in
relief by means of a transfer in the manner hereinbefore set forth and described
for that purpose.
Secondly. The transferring a design or engraving from one plate to another, and
fixing the same thereon by the process herein before set forth and described for that
purpose.
With regard to the fourth part of my Invention I claim,—
Firstly. The producing and fixing upon a plate an incrusted design either of one
uniform or of variegated tone, in the manner and by the means hereinbefore set
forth and described for that purpose.
Secondly. The producing and fixing upon a plate a design in imitation of mosaic
work in the manner and by the means hereinbefore set forth and described for
that purpose.
In witness whereof, I, the said Antoine Désiré L'Heureux, have hereunto set
my hand and seal, this Eleventh day of March, in the year of our Lord
One thousand eight hundred and eighty.
A. D. L'HEUREUX. (L.S.)