AN IMPROVED METHOD OF MANUFACTURING PAPER BY MEANS OF MACHINERY
Year: 1830

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DICKINSON, of Nash Mill, in the Parish of Abbot's Langley, in the County of
Hertford, send greeting.
WHEREAS His most Excellent Majesty did, by His Letters Patent under
the Great Seal of the United Kingdom of Great Britain and Ireland, bearing
date at Westminster, the Sixth day of October, in the first year of His
reign, give and grant unto me, the said John Dickinson, my exors, adiñňors,
and assigns, His special licence, full power, sole privilege and authority,
that I, the said John Dickinson, my exors, adññiors, and assigns, during
the term therein expressed, should and lawfully might make, use, exer-
cise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "AN IMPROVED METHOD OF MANUFACTURING PAPER
BY MEANS OF MACHINERY;" in which said Letters Patent there is contained a
proviso, that if I, the said John Dickinson, shall not particularly describe and
ascertain the nature of my said Invention, and in what manner the same is
to be performed, by an instrument in writing under my hand and seal, and
cause the same to be enrolled in His Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
Letters Patent, that then the said Letters Patent, and all liberties and advan-
tages whatsoever thereby granted, shall utterly cease, determine, and become
void, anything therein-before contained to the contrary thereof in anywise
notwithstanding.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Dickinson, do hereby declare that the following written description and
Drawing hereunto annexed contain a particular description of my said
discovery or Invention, that is to say:

page_text: In the annexed section, A and B represent two hollow cylinders in their
proper vats, prepared for the manufacture of paper according to a method
invented by myself and made public in this country by long use, and by the
various Specifications of the Patents I obtained for the Invention and subse-
quent improvements upon it; these cylinders, when set to work, are intended
to move in the direction shown by the arrows marked upon them, and the
vats are to be supplied with pulp in the usual manner.
With respect to
the process of making paper, it is sufficient to explain here that each of these
cylinders is hollow and closed at the ends, except that the axis is a fixed tube
by which water can flow out, and that the periphery is pervious to water,
and covered with fine woven-wire, so that the water of the pulp flowing
through it, the fibres of rag become deposited on the surface, and gradually
forin the paper by accumulating on any given point during its immersion in
the pulp, and the thickness of the paper results partly from the consistency
of the pulp, and partly from the rate of movement of the cylinder. The paper
formed on the cylinders A and B is detached from them at the point of con-
tact between those cylinders and two rollers working nearly perpendicular
over them, and parallel with them, marked C, C; these rollers require to
be covered with one or two coats of felting, and the purpose of them is to
bring the endless felt D into contact with the paper formed on the cylinders
A and B, and the felt is made to move in the direction shewn by. the arrows,
and at the same rate as the cylinders A and B. The paper formed upon theso
cylinders adheres to the felt D, and is continuously carried away by it. The
present improvement consists only in the mode of making the paper in two
layers or strata. The endless felt D, when it arrives at the point of contact
between the cylinder A and the roller C above it, called the couching roll, is
uncovered with paper; but supposing the machinery at work and the paper
formed on the cylinder A, the felt then takes it up and carries it away with it
to the cylinder B, on which paper is also being made, and the felt with the
paper first made adhering to it being slightly pressed down upon the cylinder B,
the paper formed upon the latter adheres to the paper first made, and they are
carried away together to the press rolls F, F, where they receive a very slight
pressure which increases the adhesion. The double paper is then drawn off
from the felt D and led on to the endless felt G, which is made to travel a little
faster, in the proportion of about thirty-seven to thirty-six, and conducts the
paper between another pair of press rolls H, H, where an additional pressure
is given, after which it is dried in the usual manner by being conducted over
cylinders heated by steam, and reeled and cut into sheets. This process is
chiefly applicable to making thick papers, & when that is the case it is facilitated
by heating the upper press rolls F & H by steam in the same manner as the

page_text: of
drying cylinders are heated. The supply of the pulp, the manufacture of the
papers, & the width and general formation of the machanery are not intended
to be different from the apparatus and system at present in use; the sole novelty
consists in bringing the paper first formed into contact with the paper formed
on the other cylinder previous to its being detatched from the felt which it is
first made to adhere to, so that being in a very wet state the two layers of
paper unite better than if either of them had been first pressed and detached
from the felt, by means of which it is led off the cylinder on which it is formed.
The rate of movement of the two cylinders A and B, and the felt D, and the
press rolls F, F, ought to correspond exactly, so that the thickness of each layer
paper must be regulated by the supply of pulp to each cylinder. The exact
arrangement of the apparatus and mode of giving motion to the different parts
is not material, and may be copied from the machinery generally in use for
the manufacture of paper; but I have described in the Drawing the method
of conducting the felt D, which I have found to answer best in practice, as
leaving the couching rollers C, C, to bear with nearly their whole weight
on the cylinders A and B, which produces a sufficient and more uniform
pressure than any other means. These rollers are solid cylinders of wood
with iron spindles or gudgeons. The endless felt marked I is for the purpose
of diminishing the pressure of the press rolls F, F. The roll marked e for
guiding the felt D, requires to be covered with felting, and occasionally cleaned,
and when the paper shews a disposition to adhere to it in preference to the
felt D, it may be counteracted by applying a little soap or oil to the surface
of the roll e.
In witness whereof, I have hereunto set my hand and seal, this Fifth
der of April in the room of our Land One thondrial
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