AN IMPROVED MODE OF MANUFACTURING PRINTING BLOCKS
Year: 1854

page_text: LETTERS PATENT to Thomas Crossley, of Scott's Yard, Bush Lane, in the
City of London, Gentleman, for the Invention of "AN IMPROVED
MODE OF MANUFACTURING PRINTING BLOCKS."-A communication.
Sealed the 18th March 1855, and dated the 4th October 1854.
PROVISIONAL SPECIFICATION left by the said Thomas Crossley at the
Office of the Commissioners of Patents, with his Petition, on the
4th October 1854.
.I, THOMAS CROSSLEY, of Scott's Yard, Bush Lane, in the City of London,
Gentleman, do hereby declare the nature of the said Invention for "AN
IMPROVED MODE OF MANUFACTURING PRINTING BLOCKS" to be as follows:-
This Invention relates to an economical. and expeditious method of applying
gutta percha, india-rubber, or other analogous gum to a wooden block, to
render its surface capable of readily absorbing color. For this purpose I take
a block of any suitable wood, and make fine saw cuts on its surface, running
at-right angles to each other, and sinking about a quarter of an inch more or
Jess below the surface, which cuts divide the surface of the block into minute:
quadrangular prisms.. These prismatic pieces I remove, except at those parts.
which correspond to the figure. required to be printed, in a manner similar to

page_text: that adopted for making blocks for printing floor- cloths; I then take sheet
gutta percha or india-rubber, and having softened it in the customary way,
lay it upon a flat surface. The block, prepared as above, I then press' upon
the softened sheet, and thereby force the plastic material-into those interstices
of the prisms which compose the figure. The prisms are thus bound solidly
and firmly together, and a surface is produced having all the absorbent qualities
of the vegetable gum, and all the strength of the wood itself, whilst it is more
economically and expeditiously made than can be done by any method with
which I am acquainted. A further advantage which this construction of
block possesses results from the fact, that the wood of which it is composed
is far less liable to warp than where felt is employed.
SPECIFICATION in. pursuance of the conditions of the Letters Patent, filed
by the said Thomas Crossley in the Great Seal Patent Office on the
3rd April 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
CROSSLEY, Gentleman, of Boston, in the County of Suffolk and State of
Massachusetts, in the United States of America, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of October, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas Crossley, Her special licence that I, the said Thomas Crossley,
my executors, administrators, and assigns, or such others as I, the said Thomas
Crossley, 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 MODE OF MANU-
FACTURING PRINTING BLOCKS," upon the condition (amongst others) that I, the
said Thomas Crossley, by an instrument in writing under my hand and seal,
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.:

page_text: NOW KNOW YE, that I, the said Thomas Crossley, 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, together with the Drawing hereto annexed, that is to say:-
Blocks for printing woolen goods have heretofore been faced with felt,
the process by which this has been accomplished being tedious and expensive.
It has been found, however, that gutta percha is far superior to felt as a
material for forming printing surfaces, and my Invention consists in an
economical and expeditious method of applying the gutta percha to a wooden
block, which method I will describe as follows:-
I take a block of maple or other suitable wood, and cover its surface with
fine saw kerfs a, running at right angles to each other, as seen in Fig. 1, and
sinking about inch more or less below the surface, as shewn in Fig. 1°;
this divides the surface of the block into minute quadrangular prisms. These
prismatic pieces are then removed from those portions of the block not covered
by the figure or design, see Figs. 2 & 2*, and are left remaining upon those
portions which are covered by the figure, in a manner similar to that adopted
for making blocks for printing floor cloths. The gutta percha is then softened
in the customary way, and laid upon a flat surface. The block, prepared as
above, is then pressed upon the gutta percha, by which means the latter is
forced into the interstices b, between the minute prisms which compose the
figure. These prisms are thus bound solidly and firmly together, and a surface
is produced having all the absorbent qualities of the gutta percha, and all the
strength of the wood itself, whilst it is more economically and expeditiously
made than can be done by any method with which I am acquainted. A
further advantage which my block possesses results from the fact, that the
wood of which it is composed is far less liable to warp than where felt is
employed; in the latter case the moisture of the colors is allowed to pass freely
through the felt to the wood, by which the latter is both warped and split.
Where the block is constructed with gutta percha, in the manner above
described, the water is effectually excluded from the wood, which is thus pro-
tected from either warping or splitting, casualties to which printing blocks, as
heretofore constructed, were more or less exposed.
CLAIM.

page_text: gutta
is, the within-described method of making printing blocks, the surface of
percha being applied to the surface-of-the-wood,-in-the-manner_and_for_the_
purpose set forth.
Witness,
SAM. COOPER.
THOMAS CROSSLEY.