CERTAIN IMPROVEMENTS IN PRINTING
Year: 1845

page_text: TO ALL
THESE RESENTS
HEATH LEWIS, of Dovor, in the County of Kent, Printer, send greeting.
JAMES
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Twenty-second day of May, in the eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Heath Lewis, Her especial license, full power, sole privilege and
authority, that I, the said James Heath Lewis, my executors, administrators,
and assigns, and such others as I, the said James Heath Lewis, my executors,
administrators, or assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN
PRINTING;" in which said Letters Patent is contained a proviso obliging me,
the said James Heath Lewis, by an instrument in writing under my hand and
seal, particularly to describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, and to cause the same to
be enrolled in Her 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
James Heath Lewis, do hereby declare that the nature of my said Invention

page_text: and the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof (that is to say) :-
The object of my Invention is to obtain, by means of the ordinary construc-
tions of platten printing presses, impressions from steel, copper, zinc, or other
engraved plates. It is well known that in very many small towns copper-plate
printing, or printing from engraved plates, cannot be performed from the want
of suitable machinery to produce the impression, and therefore it is necessary
to send such work to a distance, thus incurring expences and delays which my
improvements are calculated to prevent. The plates from which I
propose to
take impressions in letter-press printing machines are invoice heads, labels,
address cards, and such other plates as are employed by mercantile houses
generally; but the superior kinds of printing, such as proving and obtaining
impressions from large plates, may be also performed in the letter-press
printing machine if required.
My Invention refers to improvements in the construction of the tympan of
the printing press. The tympan, as it is now made, consists of light frames,
over which two skins of parchment are strained, and between them one or
more thicknesses of woollen cloth are placed, in order to produce an elastic
covering to the sheet of paper to be printed, and ease the blow of the platten
in its descent on the face of the type. Instead of the lining of woollen cloth,
I introduce between the parchments, or tympans as they are technically called,
a sheet of caoutchouc or india rubber, or gutta percha, or any other gum
possessing the requisite elasticity, cut to a thickness of about one eighth of an
inch, by which means I obtain an elastic cushion capable of entering the lines
of the plate. In working off impressions by this improvement, it will be
necessary to "block" the plates, that is, mount them on a block or metal
frame to make them type-high, similar to the plan adopted for stereotype
plates. They are then inked and cleaned off in the ordinary manner, and
placed beneath the platten, and the wet paper or card being laid over the
engraving, the tympan is brought over it, and the platten depressed as usual.
A good clear impression will be thus obtained, and without disturbing the
arrangement of the press for letter-press printing, for, by the application of
the elastic cushion, less power will be required than is at present necessary
for working off impressions from type and other raised surfaces. Another
plan of making the elastic cushion or tympan, and which I consider will be
particularly useful where the press is not kept in constant operation, is employ-
ing the india-rubber composition, commonly known as "vulcanized" india
rubber, in place of the elastic gums before mentioned.. The peculiar property
of this composition being to retain its elasticity at all temperatures, a regu-

page_text: larity in the color of the impressions will be ensured from the commencement
to the end of the working.
Having now described my Invention of improvements in printing, I wish
it to be understood that I claim, under the above in part recited Letters
Patent,
First, the application, to the tympan frame of platten printing presses, of
india rubber, gutta percha, or other suitable elastic gum, for the purposes
above mentioned.
And, secondly, the application of vulcanized india rubber to the tympan
frame of platten printing presses for the purposes above set forth.
In witness whereof, I, the said James Heath Lewis, have hereunto set
my hand and seal, this Twenty-second day of November, in the year
of our Lord One thousand eight hundred and forty-five.