AN IMPROVED METHOD OF ENLARGING OR REDUCING DESIGNS, MAPS, AND OTHER SIMILAR. ARTICLES, ALSO APPARATUS OR MACHINERY TO BE EMPLOYED IN THE SAME
Year: 1855

page_text: Scaled the 14th August 1855, and dated the 9th March 1855.
PROVISIONAL SPECIFICATION left by the said James Murdoch at the
Office of the Commissioners of Patents, with his Petition, on the
9th March 1855.
I, JAMES MURDOCH, of 7, Staple Inn, Holborn, in the County of Middlesex,
Patent Agent, do hereby declare the nature of the said Invention for "AN
IMPROVED METHOD OF ENLARGING OR REDUCING DESIGNS, MAPS, AND OTHER SIMILAR.
ARTICLES, ALSO APPARATUS OR MACHINERY TO BE EMPLOYED IN THE SAME," to be as
follows:-
The mode of enlarging or contracting designs is as follows:-A tracing of
the design is made on a sheet of gelatine (commonly known as glass paper)
by means of a steel point or tracer, and the surface is covered with black or

page_text: other colour in paste or in powder. The surface is then wiped clean from the
powder, which, however, remains in the lines made by the tracer. The tracing
thus prepared is applied with the black or colored side downwards to a sheet
of caoutchouc (or other suitable elastic material) previously slightly moistened,
and by means of pressure the design is transferred to the sheet of caoutchouc.
This sheet is then stretched equally in every direction until the design is
enlarged to the desired dimensions. A sheet of paper slightly moistened
is then placed upon the caoutchouc, and by pressure the design is transferred
from the latter to the paper. If the design is to be reduced or contracted,
the caoutchouc is to be stretched before, the design is, transferred to it, and
the design being transferred to it, the caoutchouc is allowed to shrink to the
required dimensions, and then transferred by pressure to the paper as before.
Another method of producing the design on the caoutchouc is to make a
tracing of it on paper with a steel pen and with ink composed of lamp black
burnt and pounded with molasses. This tracing is readily transferred to the
caoutchouc and from it to paper...
The process may be carried out by any suitable apparatus, but the following
is particularly claimed-It consists of a smooth circular metallic table sup-
ported on four columns. A circular tray, of somewhat larger diameter than
the table and situated beneath it, is moveable vertically by means of a screw
working in the boss of the tray, and is guided by the four columns which pass
through holes in the tray. The screw is turned by a train of wheel-work.
The sheet of caoutchouc is spread over the table, and secured to the tray by
means of a ring bolted down upon the former. By drawing down the tray
by means of the screw, the required stretching of the caoutchouc is effected.
To give the pressure for transferring the tracings, there is a platten fixed to
a lever working above the table, hinged at one end to a standard bolted to the
bed of the machine, and connected at the other by a rod to another lever
below, and which is worked by a screw.
by the said James Murdoch in the Great Seal Patent Office on the
31st August 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MURDOCH, of 7, Staple Inn, Holborn, in the County of Middlesex, Patent
Agent, send greeting.
3

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of March, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said James Murdoch, Her special licence that I, the said James Murdoch,
my executors, administrators, and assigns, or such others as I, the said
James Murdoch, 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 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 "AN IMPROVED
METHOD OF ENLARGING OR REDUCING DESIGNS, MAPS, AND OTHER SIMILAR ARTICLES,
ALSO APPARATUS OR MACHINERY TO BE EMPLOYED IN THE SAME," a commu-
nication, upon the condition (amongst others) that I, the said James
Murdoch, by an instrument in writing under my hand and seal, should par-
ticularly 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 James Murdoch, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof (that is to say):-
The improved method of enlarging designs consists in transferring to a
sheet of caoutchouc or other suitable clastic material a tracing of the design
to be enlarged, and then stretching the material equally in all directions until
the required enlargement is obtained. If a reduced copy of a design is
required, the elastic material is first stretched and a tracing of the design
is then transferred to the material, which is then allowed to contract until the
design is reduced to the required dimensions.
The transfer of the design may be effected as follows:-A tracing of the
design is made on a sheet of gelatine (commonly known as glass paper) by
means of a steel point or tracer, and the surface is then covered with black or
other color in paste or in powder, and the surface is then wiped clean from the
powder, which, however, still remains in the indented lines made by the tracer.
The tracing thus prepared is applied with the black or colored side down-
wards to a sheet of caoutchouc (or other suitable elastic material) previously
slightly moistened, and by means of pressures the design is transferred to the
sheet of caoutchouc, which is then stretched equally in every direction until

page_text: the design is enlarged to the required dimensions. A sheet of paper slightly
moistened is then placed upon the caoutchouc, and by pressure the design is
transferred from the caoutchouc to the paper.
Another method of producing the design on the caoutchouc is to make a
tracing of it on paper with a steel pen and with ink composed of lamp black
burnt and pounded with molasses. This tracing is readily transferred to the
caoutchouc and from it to the paper. The stretching of the caoutchouc and
the transfer of the design from it to a sheet of paper may be effected by any
suitable apparatus, but the Inventor prefers that represented in the Drawings
hereunto annexed, which he has invented for the purpose.
plate is a spur
Figure 1 is an clevation of the apparatus (partly in section), and Figure 2
is another elevation (partly in section), at right angles to the former, and
showing the caoutchouc stretched. a is the base plate of the apparatus, to
which are attached by screws four equidistant cylindrical columns b. A plate c
is supported by the columns b at about twelve inches distance from the base
plate, and at the top of the columns is a plate d, secured thereto by screws,
and to the top of this plate (d) is attached a smooth polished plate e, with a
bevilled edge, forming the top of the machine. Between the plates c and d is
a moveable plate f, sliding upon the columns b, b, (which serve as guides) and
moved by a screw g, which works in a nut in the plate f. The screw is
supported in a step attached to the plate c, and below the
wheel h, gearing into another wheel i, which is driven by a pinion j. The
mechanism which gives motion to the pinion j consists of a standard k, fixed
to the base plate and connected to the plate c.
This standard supports a
vertical spindle l, which traverses the pinion j, and carries at its upper end
a bevilled pinion m, which receives motion from a bevilled wheel n, which is
turned by a fly wheel and handle o. The caoutchouc a*, Figure 2, is placed
upon the plate e, and is fixed to the plate f by an iron ring p, which is secured
to the plate by a number of screws, and thus nips the caoutchouc. By
turning the handle motion is given to the wheel n, which drives the pinion m
and the pinion j, which gives motion to the wheels i and h, which causes the
screw g to turn, and thereby to draw down the plate f, as shewn in Figure 2,
and thus the stretching of the caoutchouc is effected.
The transfer of the tracing to the caoutchouc or from the caoutchouc to
the paper is effected as follows:-9 is a standard, fixed to the base plate and
to the plate c. At the upper end of this standard is a hinge joint to which is
jointed the lever 1. To the centre of this lever is attached a platten s by
straps t, t. To the end of the lever can be jointed by a pin a rod u, to the
lower end of which is jointed a counter lever v, turning upon a centre in a

page_text: step w, and having jointed to its other extremity a vertical screw a, which passes
through a bracket y, and works in a nut in the wheel z. When it is required
to transfer the design from the tracing to the caoutchouc or from the caout-
chouc to the paper, the tracing or the paper is spread upon the caoutchouc,
and the lever r, from which the platten is suspended, is brought down. The
lever is then connected to the vertical rod u, and the wheel z is turned,
which, raising the screw a, draws down the rod u, and thereby presses down
the platten.
Having thus described the Invention, and the manner of carrying out the
same, I claim in respect thereof,-
Firstly, the enlarging designs, maps, and other similar articles, by trans-
ferring the design to a sheet of caoutchouc (or other suitable elastic material),
and then stretching the material equally in all directions, and the reducing
such designs by transferring them to a sheet of caoutchouc (or other suitable
elastic material) previously equally stretched in all directions, and then
allowing the material to shrink or contract equally in all directions.
Secondly, the apparatus herein-before described for stretching the elastic
material, and for making transfers of the design to or from the elastic
material.
In witness whereof, I, the said James Murdoch, have hereunto set my
hand and seal, this Thirtieth day of August, in the year of our Lord
One thousand eight hundred and fifty-five.
Witness,
H. H. MURDOCH.
JAMES MURDOCH. (L.S.)