Illustration: FIG. 1. SECTION OF RAG ENGINE, WITH DOUBLE ROLLER.
Illustration: FIG. 2. PAPER-MAKING MACHINE.
This important article of civilisation is made from rags of various
descriptions and qualities, according to the kind of paper to be
made, the finest white paper being made of old clean linen rags,
while brown paper is made of all sorts of old rope-yarns, sacking,
&c., and some kinds of paper have a considerable amount of straw
bleached and worked up in them. The rags are first sorted and cut up
into small pieces; they are then beaten on a wire screen to separate
all dust, and afterwards put into the washing-machine, through which
a stream of water runs, and in which they are kneaded and torn by
a broad wheel having iron wedges or knives fastened to its edge
(fig. 1) or surface, which work as it is turned against knives of a
similar description fastened to the bottom of the cistern. When the
rags are thoroughly washed, and at the same time torn to a coarse
pulp, it constitutes what the workmen call “half-stuff.” This is
mixed with chloride of lime, and the machine again set in motion;
this is for the purpose of bleaching the pulp; after this has been
effected, more water is turned on, as in the first washing, and all
the chloride of lime washed thoroughly away. The pulp is now either
put into another machine of the same description which cuts sharper
and finer, or else the same machine used at first is so screwed up
as to cause the knives to come more closely together; in either case
the rate of turning is greatly increased, so that the wheel turns
at about 150 revolutions per minute, and completely grinds up the
pulp till it is perfectly smooth: at this part of the process some
“indigo” or “smalt” is added if the paper is to be of a blueish tint,
as in “foolscap” paper. The “stuff” is now run off into a cistern
ready for use. Paper is now nearly all made by machinery, in pieces
of a certain width, but of an indefinite length, and is cut up into
sheets afterwards by a “cutting machine.” These machines (fig. 2)
consist essentially of a vat, A, for the pulp, which flows out on
to a bed of wire gauze, B B B, covered with felt, and bounded on
each side by straps or deckles, and forming a circle or endless band
by being stretched over a succession of rollers, C D E F G, which,
by turning round continually, move its upper surface onwards and
between other cylinders, which press out the superfluous moisture;
it is then carried forward till it arrives at several pairs of large
hollow cylinders, H H H, heated by means of steam which is passed
through them, and which compress and at the same time thoroughly dry
the paper, which comes from them as paper perfectly formed, and of
any length that may be required. It is then glazed on the surface by
the rollers I, and coiled on the cylinder L. Any name, device, or
water-mark can be worked in the bed on to which the pulp flows, and
which, being repeated at definite distances, appears on each sheet
into which the paper is afterwards cut. The apparatus marked K is to
conduct to the earth the electricity developed by the friction of the
paper against the rollers. Beneath the bed of wire gauze, on which
the pulp is laid is a cavity from which the air is pumped, and which
causes the air to press upon the surface of the pulp, and force out
a great deal of its moisture.
Illustration: FIG. 3. SIZING MACHINE.
If the paper has to be sized (which is the case in all “hard” papers)
it has to pass through a process, the machinery of which is shown in
fig. 3. A is a reservoir for size, B a trough for the paper to dip
into, C the reel of paper to be sized, D rollers to press out all
superfluous size, E a pulley to keep the paper on the stretch, F F F
a succession of hollow “drums,” to prolong the passage of the paper
through the air of the drying-room, which is heated by the furnace
G and the tubes I I. H H are openings to admit fresh air, and K
openings to allow the exit of the steam from the paper as it dries.
L is a series of rollers to glaze it.
Illustration: FIG. 4. CUTTING MACHINE.
The “cutting-machine” before referred to is represented at fig. 4.
A is a wheel upon which is fixed a plate with projections and
screws for fixing the position of the arm attached to the link B;
B link connecting the wheel A with the lever-arm G, and capable of
adjustment by means of the plate attached to the wheel A, and the
screw D; D a screw regulating the position of the rod B; E the drum
by whose motion the web of the paper is carried forward.
Illustration: FIG. 5. HAND PROCESS.
But the process, as conducted by hand (fig. 5), will give a much
better notion of how paper is formed from the pulp. A reservoir, A,
is filled with pulp, which is supplied by a wheel in the box B, to a
strainer C, and passed to a vat D, and a man, E, takes in his hands a
mould consisting of a shallow frame of wood of the size the sheet of
paper is to be, having a bottom of fine wires laid side by side, and
having wires crossing at intervals to keep them firm (the marks of
these may be seen in any sheet of laid foolscap paper held up to the
light); he dips this mould edgewise into the reservoir, and brings
it up horizontally full of pulp; this he gently shakes, to make the
pulp lie level and allow all superfluous water to drain through the
wires. It is then handed to another man H, who has a sheet of flannel
or felt spread out on a table F G, on which the mould is inverted,
and the sheet of pulp left on the flannel, which sucks up more of
its moisture; over this is placed another piece of flannel, and then
another sheet of pulp on it, and so on to the number of five or six
dozen F, then the whole is put into a powerful press, and screwed
down till all the water is squeezed out, when they are pretty firm,
and are lifted out and hung on lines to dry, after which they are
immersed in a cistern filled with thin size made by boiling clippings
of skin in water (see “Glue and Size”), and having some alum
dissolved in it--they are once more pressed and dried. What is called
“hot-pressed” paper is pressed between smooth sheets of pasteboard,
having a hot iron plate placed between every three or four dozen
sheets of paper; this gives a smooth surface to the paper. The names,
dates, and other marks seen on hand-made paper are formed by wires
worked into the bottom of the mould, which, projecting, make the pulp
thinner in those places. The water-mark of Bank-notes is made in the
same way. More than half-a-million sterling is paid annually for duty
upon paper--so vast is the consumption!