AN IMPROVED APPARATUS AND MEANS TO BE EMPLOYED THEREWITH FOR OBTAINING COPIES OF WRITINGS, DRAWINGS, AND THE LIKE, WHICH APPARATUS IS ALSO APPLICABLE FOR OTHER PURPOSES."
Year: 1880

page_text: LETTERS PATENT to Otto Lelm, of Farringdon Street, in the City of London,
"
now temporarily of Paris, France, Merchant, for an Invention of AN
IMPROVED APPARATUS AND MEANS TO BE EMPLOYED THEREWITH FOR
OBTAINING COPIES OF WRITINGS, DRAWINGS, AND THE LIKE, WHICH
APPARATUS IS ALSO APPLICABLE FOR OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Otto Lelm at the Office
of the Commissioners of Patents on the 18th October 1880.
•
"
OTTO LELM, of Farringdon Street, in the City of London, now temporarily of
Paris, France, Merchant. AN IMPROVED APPARATUS AND MEANS TO BE
EMPLOYED THEREWITH FOR OBTAINING COPIES OF WRITINGS, DRAWINGS, AND
THE LIKE, WHICH APPARATUS IS ALSO APPLICABLE FOR OTHER PURPOSES."
The chief object of my Invention is to provide means which will enable any
person to reproduce writing, drawing, or the like, in an expeditious, cheap, and
simple manner in indelible black without using a press or any acids, and without
any troublesome washing or melting down of any compositions such as have been
heretofore used for such purposes.
My Invention comprises the use of vegetable parchment covered on both sides
with a gelatinous composition to form a printing surface, and a stretching frame
for holding the parchment printing surface, and which frame is applicable for other
purposes.
It is well known that a gelatinous surface can only be used for the reception of
a negative produced by corrosive or hardening inks when the said surface has
previously been softened in water or other suitable fluid; the necessity for this
softening is very inconvenient. If, for instance, hard substances such as zinc, copper,
glass, marble, stone, or the like, are used as bases of a gelatinous film, an oxide will
be formed on the zinc from the humidity, which will also corrode the gelatinous
film and render the reproductions or copies of the same spotty and dirty. Copper
and marble or other stone are too expensive for general use, whilst glass cannot be
advantageously used by reason of its fragility. Furthermore all hard substances

page_text: are practically useless by reason of their weight and consequent expense of
carriage. And another great disadvantage of such hard substances is that as the
temperature varies the gelatinous film is subject to expansion and contraction
different to that of its hard base, the consequence being that the gelatinous film
pulls off the base while in use. In using flexible substances such as paper, cloth,
or the like, besides the difficulty of stretching there is another drawback, viz., that
in soaking the gelatinous film the liquid always penetrates the lower side of the
material used as a base, and is therefore followed by the stripping off of the
gelatinous film when used. After various experiments to overcome the above
difficulties, I have been successful in perfecting an apparatus which will be
distinguished in every way by the simplicity of its manipulation, its cheapness,
and its great efficiency. I have found that the use of vegetable parchment is
specially useful as a base or rather medium for a gelatinous printing surface by
reason of its firmness and softness when damp, cheapness, and light weight. I pass
the parchment through a warm gelatinous composition, in consequence of which
the same becomes quite soft and extends itself evenly and without creases. In
taking the parchment out I draw the underside over a blade with a sharp but not
cutting edge fixed on the gelatine bath. By this blade the surplus gelatinous
composition taken up by the under part of the parchment will be removed, that is
to say, all except a very thin filin, while the upper gelatinous film of the parchinent
remains perfectly intact.
The parchment prepared in this manner is to be dried, and can then be used
advantageously as a printing surface after any length of time and in all climates.
Before using this prepared parchment it is to be soaked for a few ininutes in
water; the thin film of gelatinous matter on the underside is quite sufficient to
prevent the penetration of the water, and therefore to protect the parchment from
the peeling of the upper surface which is to be used as the printing surface.
The vegetable parchment can be coated on both sides with equal thickness of
gelatine, but this is not advantageous, as the drying can only be effected with
difficulty and danger of injuring one of the films, and when one side has been used
as a printing surface the other side is generally not in a condition to present a proper
printing surface. For stretching the parchment or other flexible substances,
especially for holding and stretching the parchment coated with the gelatinous film,
I have devised a frame which I will now describe.
My improved stretching apparatus is constructed as follows, that is to say :-
:-It
is made of wood or other suitable material in the form of an oblong frame. It has
an outer or main portion, within which is fitted an adjustable panel. The said
outer or main portion has a groove or channel formed in it and extending along its
four sides for the reception of a light clamping frame, and provision is made at the
four corners of the apparatus for holding the said clamping frame by hooks or
otherwise securely in place in the said groove. Below the said central panel [
arrange at the ends of the apparatus hinged or jointed pieces which can be turned
up or down on their hinges for a purpose hereinafter explained. The said
apparatus is provided with two cross bars or other suitable means for supporting it
in a level position upon a table, and it is provided with a drawer for containing
the ink and other materials and articles necessary in using the said apparatus.
Provision is made for holding a roll of the prepared parchment by forming two round
holes in the said cross pieces at the back of the drawer, the roll of parchment being
placed in these holes.
In using this improved apparatus for stretching the sheets of prepared parch-
ment or any other material, the said clamping frame is raised from its groove, and
a piece of oil-cloth or other like material should be placed on the top of the said
movable panel; the sheet of parchment (which has been damped and dried) is then
placed over the said oil cloth on the panel with its sides projecting over the said
groove or channel; the said clamping frame is then placed in its groove over the
parchment and pressed down thereon, and is secured by the hooks or other devices
.

page_text: provided at the four corners of the frame for this purpose as above specified, and
the sheet of parchment is further secured in place by passing small pins through
the grooved frame and clamping frame. The said panel when placed in the frame
is level or nearly level with the top of the frame, and the sheet of parchment or
other material when placed thereon is slack or unstretched, but the stretching and
tightening of the sheet is effected by the aforesaid hinged pieces, which are curved
or rounded on their surface in such a manner that when turned up on their hinges
they exert a powerful cam-like action on the panel and raise the same above the
surface of the frame, and thereby stretch and tighten the sheet of parchment or
other material. The said hinged pieces can be turned partially or entirely up on
their hinges to stretch the sheet more or less as required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, and
of an Order of the Lord Chancellor, filed by the said Otto Lelm in the Great
Seal Patent Office on the 11th May 1881.
OTTO LELM, of Farringdon Street, in the City of London, now temporarily of
Paris, France, Merchant. "AN IMPROVED APPARATUS AND MEANS TO BE
EMPLOYED THEREWITH FOR OBTAINING COPIES OF WRITINGS, DRAWINGS, AND
THE LIKE, WHICH APPARATUS IS ALSO APPLICABLE FOR OTHER PURPOSES."
The chief object of my Invention is to provide means for the reproduction of
writing, drawings, or the like, in an expeditious, cheap, and simple manner in
indelible black without a press or acids, and without any troublesome washing
or melting down of compositions such as have been heretofore used for these
purposes.
My Invention comprises the use of vegetable parchment, or similar material,
which is covered on one side or both sides with a gelatinous composition to form a
flexible printing surface, and which may be readily rolled up for transport, and
when slightly dampened, as hereinafter set forth, may be easily stretched without
any liability of the gelatinous coating to become detached therefrom.
The said Invention also comprises a stretching frame or apparatus for holding
and stretching such parchment or other material provided with the gelatinous
printing surface, which frame is also applicable to the stretching of paper,
parchment, linen, or the like, for other purposes. This frame is constructed of
wood or other suitable material, and is provided with a central movable panel,
which enables the requisite tension to be produced upon the sheet of paper,
parchment, linen, or the like, and serves as a support for the printing surface
during the inking of the same and the reproduction therefrom of the drawing,
writing, or other matter contained thereon. The said apparatus is also provided
with a drawer for containing the articles necessary for such reproduction, such as
the writing ink, a sponge, an inking roller, a receptacle for the printing ink, and an
ink-distributing plate for supplying the ink to the roller. This ink is thick, and of
a greasy nature, similar to ordinary printing ink, and therefore differs from the
aniline inks heretofore employed in the reproduction of writing, drawings, and
the like.
In using my Invention I immerse, for a few minutes a sheet of parchment or
other flexible material coated with gelatine, as above described, in water, and after
sponging the said sheet I stretch it upon my improved frame or apparatus. The
impression upon this sheet of parchment or other material is then obtained from a
sheet of ordinary paper, which has the writing or drawing first produced thereon
with suitable ink; this paper is then laid face downward upon the stretched
surface of the parchment or other flexible material and pressed thereon for about
two minutes, when the writing or drawing will be found reproduced reversely on
the gelatinous surface of the said material; the only operations then required
are to pass the inking roller over the said gelatinous surface and to apply a sheet
of paper which, by slight pressure of the hand, is caused to take up the ink on
such surface. I repeat the inking after each copy is taken from the gelatinous
surface, and a great number of impressions can be taken from the same, which
impressions will be perfectly clear however fine or delicate the lines of the original
may be.
The coating of the parchment, paper, linen, or other flexible material is effected
as follows, that is to say--I pass the parchment, paper, linen, or the like, through a
bath containing gelatine heated to such a degree that it is quite soft and will
spread evenly. In withdrawing the parchment or other material from the said
bath I draw its under surface over a blade with a sharp but not cutting edge, so

page_text: that the surplus gelatinous composition taken up by the said surface of the
parchment will be removed, whilst the upper gelatinous film will remain perfectly
intact. The parchment or other material prepared in this manner is dried, and can
then be used advantageously as a printing surface after any length of time and in
all climates. The thin film of gelatinous matter on the underside of the said
material serves to prevent the penetration of water, and therefore to prevent the
peeling off from the parchment or other flexible material of the upper film of
gelatine which is to be used as the printing surface. In some cases I coat the
parchment, paper, linen, or other sheet on both sides with films of gelatine of the
same thickness.
My improved stretching frame or apparatus is illustrated in the accompanying
Drawing, in which,―
Figure 1 is a plan of the said apparatus, and
Figure 2 is a longitudinal section of the same on the line x, x, Figure 1, with
the parts in their normal position.
Figure 3 is a similar longitudinal section of the said apparatus, with the panel
raised to effect the stretching of the flexible sheet.
Figure 4 is a plan of the said apparatus with the panel removed, and
Figure 5 is a transverse section on the line y, y, Figure 1.
The said apparatus is composed of a wooden oblong frame a, which rests upon
two uprights or cross-bars b. In the top of this frame is formed a groove or
channel a for the reception of a light clamping frame c. Within the central
aperture enclosed by the aforesaid oblong frame a I place the movable panel d,
which, when in its normal position, rests upon the cross-bars b, as shown in
Figure 2. Upon these bars 61 secure by means of hinges the two pieces e having
curved or rounded faces e¹. These pieces can be turned up on their hinges to cause
the said panel to rise, or may be turned down to allow the same to descend.
frepresents the drawer for containing the ink and other materials and articles
necessary in using the said apparatus. Between the aforesaid panel d and the
parchment or other material to be stretched I place a piece of oil-cloth or other
like substance whose waterproof upper surface prevents any injury to the panel
from the humidity of the parchment or other sheet stretched on the said panel,
whilst the woolly under surface of the oil-cloth affords a flexible and soft base
which ensures the perfect inking by the inking roller of the impression on the
gelatinous surface of the stretched sheet.
To effect the stretching of the sheet of parchment or other material the clamping
frame c is first raised from the groove a³, and the piece of oil-cloth or other like
material is placed upon the top of the movable panel d; the sheet is then
dampened and sponged, and is placed over the said oil cloth on the panel d with
its edges projecting over the said groove or channel a¹; the clamping frame c is
then placed in the said groove over the parchment or other sheet and pressed down
theroon, and is secured by hooks g or other devices provided at the four corners of
the frame for this purpose. The sheet is then further secured in place by passing
small pins h through the grooved frame a and clamping frame c. The panel d
when placed in the said frame is level or nearly level with the top of the same, and
the sheet when placed thereon is slack or unstretched; but the stretching and
tightening of the said sheet is effected by the aforesaid hinged pieces é, which,
when turned up into the position shewn in Figure 3, exert a powerful cam-like
action on the panel and raise the same above the surface of the frame, and thereby
stretch and tighten the sheet of parchment or other material.
The above described apparatus may obviously be utilized for stretching
parchment or other flexible material, not only for the purposes above specified, but
for any purpose for which it is desirable to obtain such materials in a stretched or
strained condition.
Having thus fully described my said Invention, and the manner of performing
the same, I wish it understood that I claim,-
First. The annaratus for stretching the parchment or paper provided with the

page_text: gelatinous printing surface or other flexible materials, constructed and operating
substantially as above set forth.
Second. The employment of a sheet of parchment, paper, linen, or similar
flexible material, coated on one or both sides with a gelatinous film for the
reproduction with greasy or thick ink of writing, drawings, or the like,
substantially as set forth.
In witness whereof, I, the said Otto Lelm, have hereunto set my hand and
seal, this Fourteenth day of April, in the year of our Lord One thousand
eight hundred and eighty one.