IMPROVEMENTS IN CASTING FOR PRINTING PURPOSES
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MOSES
POOLE, of the Patent Office, Lincoln's Inn, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster the Twentieth day of July, in the third year of Her reign, did, for Her-
self, Her heirs and successors, give and grant unto me, the said Moses Poole,
Her especial licence, full power, sole privilege and authority, that I, the said
Moses Poole, my exors, admors, and assigns, or such others as I, the said
Moses Poole, my exors, admors, or assigns, should at any agree with, and no
others, from time to time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, the Invention of
"IMPROVEMENTS IN CASTING FOR PRINTING PURPOSES," communicated to me by
a certain foreigner residing abroad; in which said Letters Patent is contained
a proviso, that I, the said Moses Poole, shall cause a particular description of
the nature of the said Invention, and in what manner the same is to be per-
formed, to be inrolled in Her said Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Moses Poole, do hereby declare the nature of the said Invention, and the

page_text: manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof :-
The Invention consists of a mode of obtaining castings of surfaces for
printing purposes by means of flexible moulds, whereby I am enabled to obtain
flat plates, or curved surfaces or forms, to be employed in printing with flat or
cylindrical printing presses. The materials of which I prefer these flexible
moulds to be composed of are a composition of paper, with paste and potters
earths well pulverized. I employ them as follows:-I take a sheet of paper
and cover it over with glue; on to this I put a thin coating of a composition
of equal parts of paste and well-powdered potters' earth, mixed in water to the
consistence of paste; on to this I put a sheet of tissue paper, and then another
coating of the composition, until the whole assumes the required thickness,
about one-eighth of an inch. The last sheet of paper should have applied to
it a coating of sweet oil. I then take the type or other surface from which I
wish to obtain an impression or mould, and place the flexible material (before
it is dry) on the surface thereof, and by pressure in any convenient manner
"obtain an exact cast of the page or form of type. This mould, together
with the forin of type, are allowed to stand for about two hours, when the
mould may
be removed from the type; but if it is required quicker, it must be
put into a stove, except when obtaining à mould or impression from a wood
engraving: If the mould is intended to be used for flat printing, it is placed
between two flat plates of metal, and suffered to remain there until perfectly
dry. The drying may be accelerated by applying sheets of blotting paper to it,
or any woollen material may be used for that purpose; but if the mould is
required of a curved form, in place of putting it between two flat platės, I use
one convex and the other concave, and of the figure the form or mould is
required to be. It should then be moderately heated in a stove, and by being
pressed between the plates will assume the form required, and when perfectly
dry they will be fit for use: In order to produce castings from such moulds, a
mould, whether curved or flat, is put between two iron or other suitable
surfaces; flat or curved according as o flat or curved mould is to be cast;
one of these surfaces has hinged thereto three narrow strips of iron, or
other suitable material; which, being raised on edge, will produce a right-
angular recess to receive the mould, and enclose it on three sides; and
the other metal surface is thereby kept at a suitable distance to obtain
the thickness of casting desired. The narrow slips of metal being of a
width equal to the thickness of the casting, and the casting two iron sur-
faces between which the mould is placed are clamped together by a screw
clamp; in this condition it will be evident that there will be the two iron

page_text: surfaces kept apart by the three strips of iron, and the mould between them,.
and a space between the face of the mould and one of the two surfaces. Into
this space, metal (such as is employed in steriotype) in a moulten state is
poured; and to facilitate the pouring, I prefer that a portion of the surface
should be removed, in order to produce a mouth or channel to guide the fluid
metal between that surface and the face of the mould (and the projection on
the back of the casting thus produced is to be removed by rasping or cutting).
In a few seconds the casting and mould may be removed by unclamping the
surfaces, removing the one forming the back of the casting, and folding down
the strips of metal, when the mould and casting will be free; and I would
observe, that with ordinary care the same moulds may be used over and over
again.
Having thus described the nature of the Invention, and the manner of
performing the same, I would observe, that although I have described a par-
ticular flexible composition of which the moulds are made, I do not confine
myself to those materials, nor to the proportions set forth, but I have found
them to be the best for the purpose; but what I claim as the Invention is the
mode of obtaining castings for printing purposes by means of flexible moulds,
as herein-before described.
In witness whereof, I, the said Moses Poole, have hereunto set my hand
and seal, this Twentieth day of January, in the year of our Lord One