IMPROVEMENTS IN THE MANUFACTURE OF PAPER
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
EVANS, of Birmingham, in the County of Warwick, Paper Manufacturer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victória, by
Her Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Fourth day of February, in the second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Evans, Her especial license, full power, sole privilege and
authority, that I, the said John Evans, my exors, adñors, and assigns, ór
such others as I, the said John Evans, my exors, adiñors, 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 "IMPROVEMENTS IN THE MANUFACTURE OF PAPER;"
in which said Letters Patent is contained a proviso that I, the said John
Evans, shall cause a particular description of the nature of my said Inven-
tion, and in what manner the same is to be performed, 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
John Evans, do hereby declare the nature of my said Invention, and
the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being

page_text: had to the Drawing hereunto annexed, and to the figures and letters marked
thereon, that is to say:-
My Invention relates to that description of machines for making paper
where a vacuum is used in order to obtain an atmospheric pressure on the
pulp, in order to express the water therefrom; and my Invention relates to
the application of a peculiar description of apparatus to such descriptions of
machines, in order to withdraw or remove the air from below a portion of the
surface of wire cloth on which the pulp is laid. And my Invention does not
otherwise alter the machinery for making paper other than applying such new
apparatus in substitution of apparatus heretofore employed for a like purpose.
According to the present means resorted to for withdrawing air from below
the surface on which pulp is laid in the process of making paper by machinery
(in order to obtain an atmospheric pressure into a vacuous vessel), it has been
usual to employ expensive air pumps, consisting of accurately formed cylinders
with pistons moving therein, which not only produce much friction in the act
of being worked, but also cost much money at their first purchase, and
subsequently, in order to keep them in repair. Now the object of my Inven-
tion is to apply apparatus of a much less costly nature, and also less liable to
derangement; and further, in case of derangement, will be found less difficult
of repair. In addition to which, such apparatus will work with less power,
owing to the parts not being subjected to so much friction as is necessarily
consequent on the use of well and tightly packed pistons working in cylinders.
The nature and construction of machines for making paper being well under-
stood, and the application of the vacuum process thereto, it will not be
necessary to enter into a particular description in this my Specificaton, but
proceed to describe the Drawing, which represents an apparatus constructed
according to my Invention.
DESCRIPTION OF THE DRAWING.
The apparatus consists of three cylinders for withdrawing the air, and the

page_text: vessels inclose the pipes d, and water is placed in the compartments or
vessels a, b, c. The three vessels f have rods g affixed to their upper ends by
which the vessels f receive motion from a three-throw crank, the vessels.
being guided in their movement in order to keep them vertical. On the
upper ends of the pipes d are valves h which open outwards, and on the upper
ends of the cylinders there are valves i, which open outwards. By this
arrangement, it will be evident that on the vessels f being raised, air will ascend
up the pipes d and enter the vessels f through the valves h; but in the
descent of the vessels f, the valves h will be closed, and the valves i will be
opened, and the air in the vessel f will pass away. It will therefore be
evident that if the exhausting pipe e be connected to the trough or air chamber
over which the wet pulp is passing, the air from below will be withdrawn, and
be the means of producing a vacuity in like manner to the air pumps hereto-
fore used.. j partly shows the air chamber or trough (by dotted lines), such
as have before been used in Foudrinere machines. It consists of a quad-
rangular trough, having a series of bars (with spaces between them) passing
across, in order to support wire cloth as closely as possible, and yet to leave
space in order to allow of the vacuum below being effective, all which is well
understood, and has been in use for many years.
And I would have it understood that I lay no claim to the employment of
vacuum in the making of paper by machines; but what I claim is the use or
application of inverted vessels, such as f, for the purpose of withdrawing air
from below the surface of the wet pulp, as herein described.
In witness whereof, I, the said John Evans, have hereunto set my band
and seal, this Second day of August, in the year of our Lord One