CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF PAPER
Year: 1835

page_text: DICKINSON AND TYERS' SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, Jonn
DICKINSON, of Bedford Row, Holborn, in the County of Middlesex, and
WILLIAM LONG TYERS, of Apsley Mill, in the Parish of King'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 Twenty-fourth day of July, in the sixth year of His
reign, give and grant unto us, the said John Dickinson and William Long
Tyers, our exors, adññors, and assigns, His especial licence, full power, sole
privilege and authority, that we the said John Dickinson and William
Long Tyers, our exors, adñiors, and assigns, during the term therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, our Invention of
"CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF PAPER;" in which said Letters
Patent there is contained a proviso that if we, the said John Dickinson and
William Long Tyers, shall not particularly describe and ascertain the nature
of the said Invention, and in what manner the same is to be performed, by an
instrument in writing under our hands and seals, or under the hand and seal
of one of us, 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 advantages whatsoever thereby granted, should utterly cease, determine,

page_text: and become void, anything therein-before contained to the contrary thereof,
in anywise notwithstanding.
NOW KNOW YE, that in compliance with the said proviso, we, the said
John Dickinson and William Long Tyers, do hereby declare that the following
written description and Drawing hereunto annexed contain a particular descrip-
tion of our said discovery or Invention (that is to say):-
The first part of our said Invention consists in the use of a series of magnets
for the purpose of extricating from the pulp of which paper is made, particles of
iron or steel which are found to be mixed up with certain materials now made
use of for the manufacture of paper, and which ultimately rust and disfigure the
sheets of paper in which they are deposited. We find the common horse-shoe
magnet most efficacious for this purpose, applied as follows, that is to say:-
The pulp is delivered to the machine intended to make it into paper, in as
diluted a state as it can be worked, and is made to flow along a trough of such
width as will produce a moderate current in a stream of about one inch and a
half depth. This trough may be from two to four feet, or thereabouts, in
width, according to the size of the machine to which the apparatus is applied,
so that the stream of pulp may be slower than is generally the case in the
supply of paper machines; and the length of the trough should be about six
or eight feet. The bottom of this trough should be made either wholly or in
part of very thin copper, and rows of magnets should be fixed across under-
neath it so as to attract such particles of iron or steel as may be in the pulp,
and cause them to settle on the bottom of the trough, from whence they
may be removed every time that the machine ceases working. This trough is
shewn in the section, Figure 1; Z, Z, Z, Z, the rows of magnets underneath
the bottom of it, which should have as much attractive force as can be given
to them, and should stand very close together in the rows, so that a great
number of them may be brought into action on the pulp, say from two hundred
to four hundred, the more the better, so as the trough be not made too long,
which might cause the pulp itself to settle. It will be observed that the part
of the trough over the rows of magnets consists of very thin plates of metal
(copper being most eligible), so as to get the attractive power into as close
operation as possible on the metallic particles flowing along in the stream of
pulp. There are obviously many other modes of applying the magnets to pulp
in its fluid state for this purpose, but we find this more simple and efficacious
than any other, and farther preferable from causing no rust or difficulty in
removing the subsiding particles, and also convenient as admitting of the
magnets being partially removed and renovated from time to time, without so
far impairing the efficacy of the apparatus as to suspend the working of the
machine to which it is applied.

page_text: The second part of our said Invention consists in a process for the arrange-
ment of the fibres of linen or other substance used for the manufacture of
paper, by a process invented by the said John Dickinson, on a revolving
cylinder with a pervious surface, and for which he, some years since, obtained
a Patent. The machines on this construction have been long in use, as shewn
in the outline section, Figure 1, and have been described very fully in Specifi-
cations of the said John Dickinson for the original Patent and sundry subse-
quent improvements on the same machinery. In this sketch, A is a vat to
which fluid pulp is continuously supplied during the operation of the machine;
B is the hollow cylinder having a pervious surface which revolves in this vat.
The ends of this cylinder are closed, excepting that one of them has a tube C,
which forms the axis or bearing for that end of the cylinder, and also a conduit
pipe for the water entering through the periphery of the cylinder during the
manufacture. This tube revolves with the cylinder in a circular opening
through the side of the vat, and by various contrivances the joint is made
water-tight, so that there is no escape for the pulp. When the machine is at
work, the different parts operating in the conversion of the pulp into paper,
revolve or move in the direction shewn by arrows. The vat A being supplied
with fluid pulp at the time the cylinder B is made to revolve in it, the water
flows through the periphery of the cylinder, which is covered by a woven wire,
and runs out through the central tube C, which is carried through the side of
the vat. When the surface of the revolving cylinder B descends into the
fluid pulp, it is entirely uncovered; but during the whole of its immersion the
water which, as before mentioned, runs through the periphery, deposits thercon
the fibres of rag floating in it, and these accuinalute on any given point during
its revolution in the pulp from X to Z, thereby forming the paper. E is an
endless felt, like a jack towel, which is slightly pressed on the newly made wet
paper by the couching roll D, and the paper then adheres to the felt, and is
entirely detached from the cylinder B, and carried to the press rolls F, F,
where it is pressed and led off from the felt E, for the purpose of being con-
ducted to subsequent further pressure, drying, cutting, &c. This machinery
having been long in public use, we think it unnecessary to state more parti-
cularly the process of its working or the dimensions or the mode of giving
motion to the different parts of it. It has been found that in paper manu-
factured by this process, the fibres of rag range themselves on the surfaco
of the cylinder chiefly in parrallel direction in the line of the movenient of
the cylinder, which, being in some respects disadvantageous to the texture of
the paper, our second Improvement consists in causing, by the following means,

page_text: a transverse and diagonal deposit of some of the fibres which form the paper
by the aforesaid process. The vat A is for this purpose formed of the shape
shown in Figure 2, that is to say, the lower part commencing about the level
of the centre of the making cylinder B, is scalloped at the bottom, the upper
edge of the partitions between each hollow being parrallel with the axis of the
cylinder, and continued across the vat, and approaching within a quarter of an
inch of the periphery of the making cylinder B, each partition being at the
same time thin, but rounding, so as not to have a cutting edge; and it is
intended that the pulp should be fed into these scallops or troughs at each end,
so that there may be a current along each scallop at right angles, or nearly so
with the motion of the cylinder B. The draught into the cylinder B, in the
course of the manufacture, being very considerable, would of itself cause some
current; but we make it much greater by the following contrivance, more
particularly explained in section, Figure 2, and the plan, Figure 8, and also in
the plan Figure 4, which is not formed to represent the vat A in its proper
shape, but is only for shewing that scalloped part and the pipes and apertures
now contrived for the circulation of the pulp, and is supposed to be laid down
flat like the tail of a lobster opened, The lines c, c, c, shew the top of the
partitions; the circular holes d, d, d, are the openings from two side pipes
L, L, through which a stream of pulp is supplied to each scallop. The
holes e, e, e, communicate to a pipe H, which has no other communication.
with the vat A than these holes or short tubes. It will be observed in the
section, Figure 2, that one end of this pipe, at the point marked f, is as high
as the top of the vat A, the other end marked g, though it goes through
the vat A by a water-tight passage, does not communicate with the vat,
but comes up into a small cistern or vat I, the top of which is as high as
the top of the vat A, and the bottom of it about eight inches below it.
In this vat I, there is a small water wheel K, which is made to revolve
five or six times per minute in the direction shewn in the section, Figure 2,
and this lifts up the stuff or pulp from the end of the pipe H, and delivers it
again into the vat A, at a higher level than the end of the pipe at the point
marked g. The greater portion of the pulp supplied to the cylinder B is
conveyed by two semicircular ducts or pipes L, L, which are at the sides of
the vat A, at the out ends of the scallops. These pipes are shewn more parti-
cularly in the transverse section, Figure 5, in which the holes d, communicating
with the respective scallops, are shewn; and the curve of the upper part of
these pipes is meant to correspond with the circumference of the making
cylinder B, and like the upper edge of the dividing plates between the scallops,

page_text: to approach it within a quarter of an inch or thereabouts. The orifices at the
ends of these pipes are not intended to be much higher than the centre of the
cylinder, otherwise they would interfere with the fixation and removal of it;
but the ends of the cylinder B must be so near the sides of the vat A, that the
pulp supplied to the back part of the cylinder must pass chiefly through these
pipes, or the space between the ends of the cylinder must be diminished by
fixing some thin plates edgeways to reduce the passage on each side to the
width of about a quarter of an inch. The elevation of the pulp from the point g,
by the rotation of the water wheel K, causes a rapid current through the pipe
H, the pulp for which, being supplied from the pipes L, L, causes a circulation
along the scallops from the holes d in the pipes L, L, to the holes e, which
communicate to the pipe H, and the stream of pulp along each scallop is
parrallel to the axis of the cylinder; and as the fibres are gradually depositing
themselves on the surface of the cylinder during its revolution through the
pulp, these currents lodge many of the fibres in a diagonal direction. The
plan and arrangement of these pipes and ducts for giving a circulation to the
pulp during the process of manufacture, might be very much varied. The
scallops might be somewhat curved or made diagonal, and the influx of pulp
might be made by a pipe near the centre, while the back current might be
carried through pipes at the sides. But it is unnecessary to go into detail of
such variations, the mode above specified being the most simple, and
answering the purpose. The scallops are made deeper at the ends next the
pipes L, L, than towards the centre of the vat; and it is rather preferable to
make them wider and deeper at the side of the vat nearest the small water
wheel K; and the holes a, a, should also be larger, as they have most pulp to
supply; and the bottom scallops should be shallower than the others, in order
to accelerate the circulation of pulp in them, otherwise the fibres settle and
accumulate, and form an obstruction to the action of the machine. The
motion to the small water wheel K may be communicated by any convenient
means at about the rate before specified; and the pipes and openings may be
in some degree reduced for a machine of smaller dimensions, but it is incon-
venient to have them small, and the current may be otherwise reduced by
retarding the motion of the water wheel K.
In witness whereof, I, the said John Dickinson, have hereunto set my
hand and seal, this Twenty-first day of January, in the year of our
Lord One thousand eight hundred and thirty-six.
JOHN (L.S.) DICKINSON.

page_text: AND BE IT REMEMBERED, that on the Twenty-first day of January,
in the year of our Lord 1836, the aforesaid John Dickinson came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Twenty-first day of January, in the year of our Lord One
thousand eight hundred and thirty-six.