_J.W. Butler Paper Company_
Though the steady march of progress and invention has given to the
modern paper-maker marvelous machines by which the output is increased a
thousandfold over that of the old, slow methods, he still has many of
the same difficulties to overcome that confronted his predecessor. While
the use of wood pulp has greatly changed the conditions as regards the
cheaper grades of this staple, the ragman is to-day almost as important
to the manufacturer of the higher grades as he was one hundred years ago
when the saving of rags was inculcated as a domestic virtue and a
patriotic duty. Methods have changed, but the material remains the same.
In a complete modern mill making writing and other high-grade papers,
the process begins with unsightly rags as the material from which to
form the white sheets that are to receive upon their spotless polished
surface the thoughts of philosophers and statesmen, the tender messages
of affection, the counsels and admonitions of ministers, the decisions
of grave and learned judges, and all the
Wisdom of things, mysterious, divine, that
Illustriously doth on paper shine,
as was duly set forth in rhyme by the _Boston News Letter_ in 1769.
"The bell cart will go through Boston about the end of next month," it
announced, and appealed to the inhabitants of that modern seat of
learning and philosophy to save their rags for the occasion, and thus
encourage the industry.
The rags do not come to the mammoth factories of to-day in bell carts,
but by the carload in huge bales gathered from all sections of this
great Republic, as well as from lands beyond the eastern and western
oceans. The square, compact, steam-compressed bundles are carried by
elevators well up toward the top of the building, where they await the
knife of the "opener." When they have been opened, the "feeder" throws
the contents by armfuls into the "thrasher." The novice or layman,
ignorant of the state in which rags come to the mill, will find their
condition a most unpleasant surprise, especially disagreeable to his
olfactory nerves. Yet the unsavory revelation comes with more force a
little farther on, in the "assorting-room." The "thrasher" is a great
cylindrical receptacle, revolving rapidly, which is supplied with long
wooden beaters or arms passing through a wooden cylinder and driven by
power. When the rags have been tossed in, there ensues a great pounding
and thrashing, and the dust is carried off in suction air-tubes, while
the whipped rags are discharged and carried to the "sorting" and
"shredding" room. Here the rags are assorted as to size, condition, and
the presence of buttons, hooks and eyes, or other material that must be
removed. Then those that need further attention are passed on to the
"shredders," these as well as the "sorters" being women. The
"shredders" stand along a narrow counter; in front of each one there is
fastened a long scythe-blade with its back toward the operator and its
point extending upward, the shank being firmly fixed to the table or
operating board. Here buttons, hard seams, and all similar intruders are
disposed of, and the larger pieces of rags are cut into numerous small
ones on the scythe-blades. The rags thus prepared are tossed by the
women into receptacles in the tables. The work in this room is the most
disagreeable and unwholesome in the entire process of manufacture, and
this despite the fact that these rags, too, have been thrashed, and
freed from an amount of dust and dirt beyond belief.
While one is watching the operations carried on here, it is impossible
to repress the wish that rags might be bought otherwise than by the
pound, for, unfortunately, filth, dust, and dirt weigh, and to wash rags
only reduces the weight. While this is a true reflection of the
condition in the average mill, it is pleasant to know, however, there
are others of the higher class that are decided exceptions as far as
dust and dirt are concerned. Such are the mills making high-grade ledger
and bond papers, as well as the mill manufacturing the paper that is
used for the printing of our "greenbacks," to which further reference
will be made later. In these exceptional mills everything is neat and
perfectly clean, all the stock used being new and fresh from the cotton
or linen mills, or from factories producing cloth goods, like shirt and
corset factories, and others of the same sort. The sorting and shredding
room is always large and light, with windows on all sides, and well
ventilated, offering a decided contrast in many respects to the less
cleanly mills first referred to where the women must wear bonnets or
hoods for the protection of the hair. In either case the process is
certainly an improvement over the old plan of leaving the rags to decay
in a cellar to expedite the removal of the glutinous matter from them.
From the "sorting" and "shredding" room the rags are conveyed to the
"cutter," where they are cut and chopped by revolving knives, leaving
them in small pieces and much freer from dust and grit. Various
ingenious devices are employed for removing metal and other hard and
injurious matter, magnetic brushes serving this purpose in some mills.
When the "cutter" has finished its work, the still very dirty rags go
for a further cleansing to the "devil," or "whipper," a hollow cone with
spikes projecting within, against which work the spikes of a drum,
dashing the rags about at great speed. Human lives are often freed of
their baser elements and restored to purity and beauty through the
chastening influences of tribulation or adversity; in like manner the
"whipper" carries the rags forward a step in the process of purification
that is necessary before they can be brought to their highest
usefulness. But the cleansing process, which is only a preparation for
what is to follow, does not end with the "whipper," which has served
merely to loosen, not to dislodge, a great deal of dust and dirt. The
final operation in the preliminary cleaning is performed by the "duster"
proper, which is a conical revolving sieve. As the mass of rags is
tossed and shaken about, the loosened dust is carried away by the
suction of the air, which draws the dust particles into tubes furnished
with suction fans. In most modern mills the rags are carried forward
from the "duster" on an endless belt, and a careful watch is kept upon
them as they emerge to detect the presence of unchopped pieces, buttons,
or other foreign substances. The journey of the rags over this endless
belt or conveyor terminates in a receiving-room, in the floor of which
there are several openings, and immediately below these the mouths of
the "digesters," which are in a room beneath. The "digesters," as they
are suggestively and appropriately termed, are huge revolving boilers,
usually upright, which often have as great a diameter as eight feet,
with a height of twenty-two feet and a digestive capacity of upward of
five tons of rags each. The rags that are to be "cooked" are fed in to
the "digesters" through the openings in the floor, and the great movable
manhole plates are then put in place and closed, hermetically sealing
the openings or mouths through which the boilers have been fed, these
having first been charged with a mixed solution of lime and soda and
with live hot steam in lieu of gastric juice as a digesting fluid and
force. In some mills the boilers are placed in a horizontal position,
while in others they are in the form of a large ball or globe, in either
case being operated in the manner described; those of upright form,
however, are most commonly in use. The rags are boiled under steam
pressure of about forty pounds to the square inch, and the cooking is
continued from twelve to fourteen hours.
It is here that the process of cleaning begins in earnest; and as the
mass of rags is tumbled about in its scalding bath of steam-heated
lime-water, or "milk of lime," the coloring and glutinous matters, as
well as all other impurities, are loosened from the fibers, which are in
the end so cleansed and purified as to come forth unstained and of
virgin purity. Having been sufficiently boiled and digested, the mushy
material, still looking dark and forbidding, is emptied onto the floor
below or into receptacles placed directly beneath the boilers, where the
color and dirt are allowed to drain off. The mass is then conveyed to
the "washers," great tub-like receptacles, which are known as
"Hollanders," from the fact that these rag engines were invented in
Holland about the year 1750 A.D. They are oval-shaped tubs, about twenty
feet long, nine feet wide, and three feet high, varying somewhat
according to the conditions. Each tub is divided for two-thirds of its
length by an upright partition, or "mid-feather," as it is called, which
makes a narrow course around the vat. On one side of the partition, the
tub is raised in a half-circle, close to which revolves an iron roll
about three or four feet in diameter, and covered with knives; in the
bottom of the tub, and directly under the revolving roll, is another set
of knives called a "bed-plate," which is stationary, and against which
the roll can be lowered. But let us not anticipate. When the emptyings
from the boiler have been thrown into the "washer," a continuous stream
of water is turned in at one end, the knife-roll having been adjusted so
as to open up the rags as they are set in motion. These then begin a
lively chase around the edge of the vat, through the race-course formed
by the "mid-feather," and under the rag-opening knives, where the water
is given a chance to wash out all impurities, then on up the incline
over the "back-fall," so-called from the elevation in the tub. A
cylinder of wire-cloth, partly immersed in the moving mass, holds back
the now rapidly whitening fibers, while the dirty water escapes into
buckets inside the wire-cloth drum, and is discharged into and through
an escape-spout. The heavy particles of dirt settle into what is termed
a "sand-trap" at the bottom of the tub.
As the water clears, the roll is lowered closer and closer to the bottom
of the bed-plate, in order to open up the fibers more thoroughly for the
free circulation of the water among them. When the several agencies of
the "washer" have accomplished their purpose and the water runs clear
and unsullied, a bleaching material is put into the mass, which in the
course of from two to six hours becomes as white as milk. The dirty
offscourings of all ragdom, first seen in the original bales, and
gathered from the four corners of the globe, have endured many
buffetings, many bruisings and tribulations, and having been washed come
forth pure, sweet, and clean. From the washers the rags are precipitated
through a trap into drainers, which are chambers made of stone and
brick, with a false bottom through which the water is allowed to drain.
This rag pulp, now called half stock, is kept in this receptacle until
the water and liquor are thoroughly drained off, when it becomes a white
and compact mass of fibers.
The rags should stand in the drainers for at least one week, though
better results are obtained if they are left for a period two or three
times as long, as the fibers become more subdued. The process of
paper-making as it has already been described, applies more
particularly to papers made from rags. To-day, a very large proportion
of the cheaper papers are made from wood, either entirely or in part,
and these wood-made papers are subjected to a different treatment, to
which further reference will be made.
From the drainer the mass is carted to the beating engine, or "beater,"
which is very similar in construction to the washer just described. The
knives on the roll in the beater are grouped three together instead of
two, and are placed nearer the bottom or bed-plate in order to separate
more thoroughly the fibers. In the beater are performed many and varying
manipulations, designed not only to secure a more perfect product but
also to produce different varieties of paper. It is the theory of the
beating process that the fibers are not cut, but are drawn out to their
utmost extent. In watching the operations of the "beater," one notices
on the surface of the slowly revolving mass of fibers, floating bluing,
such as the thrifty housewife uses to whiten fine fabrics. This familiar
agency of the laundry is introduced into the solution of fibers with the
same end in view that is sought in the washtub--to give the clear white
color that is so desirable. Many of the inventions and discoveries by
which the world has profited largely have been due primarily to some
fortunate accident, and according to a pretty story upon which
paper-makers have set the seal of their belief for more than one hundred
and fifty years, the use of bluing was brought about in the same way.
About the year 1746, so runs the story, a Mrs. Buttonshaw, the wife of
an English paper-maker, accidentally dropped into a tub of pulp the bag
of bluing, or its contents, which she was about to use in a washing of
fine linen. Frightened at what she had done and considering it the part
of wisdom to keep silence, she discreetly held her peace and awaited
results. But when her husband had expressed great wonder and admiration
over the paper made from that particular pulp, and had sold it in London
at an advance of several shillings over the price of his other paper,
which had not met with any such accident, she realized that the time for
silence had passed. Her account of the happy accident led her grateful
husband to purchase a costly scarlet cloak for her on his next visit to
London town. This accident brought about another result which was to
prove of inestimable value to the future paper-maker--the use of bluing
in paper when especial whiteness is desired.
Important as the bluing or coloring is, however, it is only one of the
numerous operations or manipulations that take place in the beater. Many
of these, such as engine-sizing and body-coloring, require skill and
constant watchfulness. Here, too, if anywhere, adulteration takes place.
It is sometimes necessary to secure a fine-appearing paper at small
cost, and it is profitable to add to its weight. In such cases a process
of "loading" takes place here, and clay or cheap, heavy fibers are
added. Clay is of value not only to increase the weight but also to
render the paper more opaque, so as to prevent type or illustrations
from showing through, while at the same time it makes possible a
smoother surface by filling the pores in the paper. But while it adds to
the weight, clay must, of necessity, weaken the paper. In engine-sizing,
which is done in the beater, the size is thoroughly incorporated with
the fibers as these revolve or flow around the engine. This sizing
renders the paper more nearly impervious to moisture. The difference
between a paper that is sized and that has a repellent surface which
prevents the ink from settling into it when it is written upon, and an
ordinary blotting-paper with its absorbent surface, is due entirely to
the fact that the former is most carefully treated with sizing both in
the beating engine and in the size tub or vat referred to later, whereas
in the latter paper it is omitted. If the paper is to be tinted or
body-colored, colors made from aniline are generally used. Only in the
highest grade of writing-paper and in some few papers that demand colors
fast to the light is any other order of coloring matter employed. As may
be easily imagined, considerable skill is required to secure exactly the
desired tint, and to get the coloring matter so evenly mixed that each
small fiber shall receive its proper tint, and thus to insure that the
paper when finished shall be of uniform color and not present a mottled
appearance.
When the operations of the beating engine have been completed, a most
interesting process begins which marks a vast advance over the earlier
method of forming the sheets of paper with mould and deckel, straining
off the water, and shaking the frame with a quick motion to mat the
fibers together. The patient striving toward something better which has
marked all the centuries since man first learned to carve his rude
records, finds its consummation in the process of making paper in a
continuous web. This result is accomplished by a machine first invented
by Louis Robert, a workman in a mill at Enonnes, France, who obtained a
French patent, with a bounty of eight thousand francs for its
development. This he later sold to M. Didot, the proprietor of the mill,
who crossed the Channel into England, where, with the aid of a skilled
mechanic, the machine was in a measure perfected, and then sold to Henry
and Sealy Fourdrinier. They, with the further aid of Bryan Donkin, their
employee and expert engineer, made many additional improvements, and
sank in the enterprise some sixty thousand pounds sterling, for which
their only reward was blighted hopes and embittered lives. In 1847 the
London _Times_ made a fruitless appeal on behalf of the surviving
brother, who was eighty years of age and in great poverty. It is seldom
that the world voluntarily makes return to those who have bestowed upon
it great material or moral benefits, though it is ever ready to expend
its treasure for engines of destruction and to magnify and reward those
who have been most successful in destroying human life.
The first "machine" mill was started at Frogmore, Hertz, England, in
1803, which was the year of the great Louisiana Purchase by the United
States, and it is not difficult to say which event has been productive
of the greater and more beneficial results to this nation. Through this
invention and its improvements, the modern newspaper and magazine, with
their tens and hundreds of thousands of copies daily, have been made
possible, and men of all classes have been brought in touch with the
best thought of the day. Whatever makes for greater intelligence and
enlightenment throughout a nation makes for the greater stability of
the national life, and gives new emphasis to Bulwer's words:
Take away the sword; States can be saved without it--bring the pen.
If to-day the power of the pen over the sword is greater than it has
ever been before, its increased and increasing influence must be
credited in large measure to the inventive genius and the
public-spirited enterprise that has made possible the great output of
our modern paper-mills. So thoroughly did these forces do their work in
the beginning that in the century that has elapsed since the Fourdrinier
brothers sacrificed themselves and their means in the perfecting of
their machine, there have been really no changes in the fundamental
principle. Those that have been made have been in the nature of further
development and improvement, such as increasing the speed and widening
the web, thereby multiplying the product many fold.
But let us resume the interesting journey of the rags, which had reached
a state of purification and perfection as pulp, and which we left in the
beaters. In some grades of paper the perfected and prepared pulp is
taken from the beaters and passed through what is known as a "refining"
or "Jordan" engine for the purpose of more thoroughly separating the
fibers and reducing them to extreme fineness. The refining engines are,
however, used only in the manufacture of certain grades of paper. The
pulp is next taken from the beater or refining engine, as the case may
be, to what is called a "stuff-chest," an inclosed vat partly filled
with water, in which a contrivance for shaking and shifting, properly
called an "agitator," keeps the fibers in suspension.
From the stuff-chest the mixture is pumped into what is known as the
"mixing" or "regulating" box. Here the stream first passes over the
"sand-tables" in a continuous flow. These are composed of little troughs
with cross-pieces, and are covered at the bottom with long-haired felt,
to catch any sand or dirt that may still adhere after the numerous
operations to which the pulp has been subjected. The flow is then forced
through the "screen," which is a horizontal piece of metal pierced with
slots. For very fine paper these slots are so small as to be only one
one-hundredth of an inch in width. They are usually about a quarter of
an inch apart. Through these tiny apertures the fibers must find their
way, leaving behind in their difficult passage all lumps, dirt, or
knotted fibers which would mar the perfection of the product toward
which they are tending. A vibrating motion is given to the screen as the
flow passes over it, or revolving strainers may be used.
When the screen has finished its work, the water carrying the pulp in
solution flows in an even stream, the volume of which varies according
to the width of the web of paper to be produced, through a
discharge-cock onto the Fourdrinier or cylinder machine, as the case may
be, each of which will be duly described. This stream has a filmy
appearance and is of diverse color, depending upon the shade of paper to
be produced. From its consistency, which is about that of milk, it is
difficult to imagine that it floats separate particles of fiber in such
quantities as, when gathered on the wire cloth and passed to a felt
blanket and then pressed between rollers, to form in a second of time a
broad web of embryo paper sufficiently strong and firm to take definite
form. Man's mastery of the process by which this startling and wonderful
change is effected has come as one of the rewards of his long and
patient study.
The Fourdrinier machine, which preserves at least the name of the
enterprising developers of the invention, takes up the work that was
formerly done by the molder. The wire cloth upon which the fibers are
discharged is an endless belt, the full width of the paper machine. Upon
this the fibers spread out evenly, being aided by a fan-shaped rubber or
oil cloth, which delivers the smooth stream under a gate regulated to
insure perfect evenness and to fix uniformly the fibers of the web now
commencing its final formation. Deckel-straps of india-rubber are
fastened on both sides of the wire screen, and move with it, thus
holding the watery pulp in place. The deckel-straps are adjustable and
fix or regulate the width of the paper. These and the gate, or "slicer,"
are attached to what is termed the deckel-frame, which corresponds to
the deckel used by paper-makers in the days when the manufacture was
carried on by hand. As the stream flows onto the endless belt of wire
cloth, the water which has borne the fibers filters into the trough
beneath. Being charged with very fine fibers, size, coloring matter, and
other similar ingredients, it is carried back into the pulp-chest to
save these materials, as well as to contribute again to the extra supply
of water needed. For this reason the trough into which it falls from the
revolving "wire" is called the "save-all." A shaking motion is imparted
to the "wire" from the frame upon which rest the rolls that keep it in
its never-ending round. This aids in draining away the water and mats or
interlaces the fibers together. At the end of the "save-all," where the
fibers are to leave the "wire" for the next stage of their journey,
suction-boxes are placed, provided with an air-pump to take up the
surplus water that has not yet found its way through the meshes. Between
these suction-boxes above the wire is a wire-covered roll which
impresses the newly formed sheet; this impression cylinder is called a
"dandy roll," and it is from this that the web receives the markings or
impressions that characterize different papers. All watermarks,
patterns, and designs which it is desired to have appear in the paper
are put upon this roll and here impressed upon the soft sheet, which is
clarified and left transparent at the point of contact. Thus the
impression is permanently fixed in the fiber, so that it can be seen at
any time by holding the sheet to the light. The power of suggestiveness
is a quality which is highly esteemed wherever it is found, and which
frequently furnishes a standard of judgment.
Judged by such a criterion, the impression cylinder, or "dandy roll,"
has an added value, for in all probability its operation suggested the
idea of printing from cylinders, as in our present web or perfecting
presses.
The matted pulp, now having sufficient body, passes on between two rolls
covered with felt which deliver the web of damp paper upon an endless
belt of moist felt, while the "wire" passes under and back to continue
a fresh supply. The paper is as yet too fragile to travel alone, and
the web felt carries it between two metal rolls called the first
press-rolls. These squeeze out more water, give a greater degree of
compactness to the fibers, smooth the upper surface, and finally deliver
the web of paper to a second felt apron which carries it under and to
the back of the second press-rolls. In this way the under surface comes
to the top, and is in its turn subjected to the smoothing process. A
delicate scraper or blade, the length of the press-rolls, is so placed
on each roll that should the endless web from any cause be broken, the
blade may operate with sufficient force to prevent the wet paper from
clinging to the rolls and winding about them. From this point the paper
travels alone, having become firm and strong enough to sustain its own
weight; passing above the second press-rolls, it resumes its onward
journey around the drying cylinders, passing over and under and over and
under. The drying cylinders are hollow and heated by steam, their
temperature being regulated according to requirements. These driers,
made from iron or steel, are usually from three to four feet in diameter
and vary in length according to the width of the machine. There are from
twelve to fifty of these cylinders, their number depending upon the
character and weight of the paper to be produced, very heavy sheets
requiring many more drying cylinders than sheets of lighter weight.
Strange, almost phenomenal, conditions come about in the transformation
from filmy pulp to finished paper. A sheet which, though formed, is at
the first press-roll too fragile to carry its own weight, becomes
possessed of a final strength and power that is almost incredible. The
myriad of minute fibers composing the sheet, upon drying uniformly,
possesses great aggregate strength. A sheet of paper yields readily to
tearing, but the same sheet, when a perfectly even tension is applied,
will demonstrate that it is possessed of wonderful resisting power. In
evidence may be cited an instance that seems almost beyond belief.
Through some curious mishap a web of heavy paper, in fact, bristol
board, which had been thoroughly formed, was suddenly superheated and
then cooled while still on the driers. This was caused by a difference
in temperature of the driers and resulted in the sudden contraction of
the web of bristol; the strain on the machine was so great that not only
were the driving-cogs broken on two of the driers around which the paper
was at the moment passing, but the driers themselves were actually
lifted out of place, showing a resisting power in the paper of at least
several tons. The paper now passes to the upright stack of rolls which
are known as "calenders." The word is derived from calendra; a
corruption of cylindrus, a roller or cylinder. They are simply rollers
revolving in contact, and heated from the interior by steam. These
calenders are used for giving to the paper a smooth and even surface,
and are also employed in the smoothing and finishing of cloth. The speed
with which the paper passes through these cylinders is remarkable, from
one hundred to five hundred feet running through and over the machine in
a minute; and in some of the most recent mills the web is as wide as one
hundred and fifty-six inches (thirteen feet); this is very nearly double
the average machine width of a very few years ago, while the speed has
increased in proportionate ratio; only a few years ago the maximum speed
was from two hundred and fifty to three hundred feet per minute; at this
writing (1900) there are machines in operation which run as high as five
hundred feet per minute. But great as has been the increase in the
production of paper, the demand has kept pace steadily. The wonderful
product of the rag-bag holds an invincible position in the world's
economy.
For machine-finished book and print papers, as well as for other cheaper
grades, the process ends with the calenders, after which the paper is
slit into required widths by disc-knives which are revolving, and so cut
continuously. Paper intended for web newspaper presses is taken off in
continuous rolls of the widths required, varying from seventeen to
seventy-six inches, according to the size of the paper to be printed.
These reels contain from fifteen to twenty-five thousand lineal feet of
paper, or from three to five miles. The amount of paper used in
disseminating the news of the day is enormous; sometimes one or two
mills are required to manufacture the supply for a single metropolitan
daily, while one New York newspaper claims to have used four hundred and
fifty tons of paper in one Christmas edition, which is about four times
the amount of its regular daily consumption.
After having been slit into the proper widths by the revolving knives,
ordinary flat and book papers are cut into sheets by a straight knife
revolving at proper intervals on a horizontal drum. The paper, in
sheets, is carried by a travelling apron to a receiving table at the end
of the machine, where the sheets as they fall are carefully examined by
experts, usually women, who remove any that may be imperfect.
The entire length of a paper machine, from the screens to the calenders,
is about one hundred and twenty-five feet, while the height varies, the
average being about ten feet. The machines, while necessarily of the
finest adjustment, are ponderous and heavy, weighing in some cases as
much as four hundred tons, this being the weight of the machine itself,
exclusive of its foundations. The machine-room is of necessity well
lighted and thoroughly ventilated, and should be kept clean throughout,
as cleanliness is an essential factor in the making of good paper. While
the same general process applies to all classes of paper made, the
particular character of any paper that is to be produced determines
exactly the details of the process through which it shall pass and
regulates the deviations to be made from the general operations in order
to secure special results. For example, some papers are wanted with a
rough or "antique" finish, as it is called; in such cases calendering is
omitted. Another special process is that by which the paper is made with
a ragged or "deckel-edge;" this result is obtained in some mills by
playing a stream of water upon the edge of the pulp, crushing and
thinning it, and thus giving it a jagged appearance. At the present time
this "deckel-edge" paper is being quite extensively used in high-class
bookwork. In the case of writing papers, as has already been stated in
the description of the beating engines, a vegetable sizing made from
resinous matter is introduced into the paper pulp while it is still in
solution, and mixes with it thoroughly, thus filling more or less
completely the pores of the pulp fibers. This is found sufficient for
all ordinary book-papers, for papers that are to be printed upon in the
usual way, and for the cheapest grades of writing-paper, where the
requirements are not very exacting and where a curtailment of expense is
necessary. For the higher grades of writing-paper, however, a distinctly
separate and additional process is required. These papers while on the
machine in web form are passed through a vat which is called the
size-tub, and which is filled with a liquid sizing made of gelatine from
clippings of the horns, hides, and hoofs of cattle, this gelatine or
glue being mixed with dissolved alum and made fluid in the vat. Papers
which are treated in this way are known as "animal," or "tub-sized."
We have duly described machine-dried papers, but these higher grades of
writing-papers are dried by what is known as the loft, or pole-dried
process. Such paper is permitted to dry very slowly in a loft specially
constructed for the purpose, where it is hung on poles several days,
during which time the loft is kept at a temperature of about 100°
Fahrenheit.
Another detail of considerable importance is that of the "finish" or
surface of the paper. When paper with a particularly high or glossy
surface is desired, it is subjected to a separate process, after leaving
the paper machine, known as supercalendering.
"Supercalendering" is effected by passing the web through a stack of
rolls which are similar to the machine calenders already described.
These rolls are composed of metal cylinders, alternating with rolls made
of solidified paper or cotton, turned exactly true, the top and bottom
rolls being of metal and heavier than the others; a stack of
supercalenders is necessarily composed of an odd number of rolls, as
seven, nine, or eleven. The paper passes and repasses through these
calenders until the requisite degree of smoothness and polish has been
acquired. The friction in this machine produces so much electricity that
ground wires are often used to carry it off in order that the paper may
not become so highly charged as to attract dust or cause the sheets to
cling together. When the fine polish has been imparted, the rolls of
paper go to the cutting machines, which are automatic in action, cutting
regular sheets of the required length as the paper is fed to them in a
continuous web. In the manufacture of some high grades of paper, such as
linens and bonds, where an especially fine, smooth surface is required,
the sheets after being cut are arranged in piles of from twelve to
fifteen sheets, plates of zinc are inserted alternately between them,
and they are subjected to powerful hydraulic pressure. This process is
termed "plating," and is, of course, very much more expensive than the
process of supercalendering described above.
From the cutters, the sheets are carried to the inspectors, who are
seated in a row along an extended board table before two divisions with
partitions ten or twelve inches high, affording spaces for the sheets
before and after sorting. The work of inspection is performed by women,
who detect almost instantly any blemish or imperfection in the finished
product as it passes through their hands. If the paper is to be ruled
for writing purposes, it is then taken to the ruling machines, where it
is passed under revolving discs or pens, set at regular intervals. These
convey the ruling ink to the paper as it passes on through the machine,
and thus form true and continuous lines. If the paper is to be folded
after ruling, as in the case of fine note-papers, the sheets pass on
from the ruling machine to the folding machines, which are entirely
automatic in their action. The paper is stacked at the back of the first
folding guide and is fed in by the action of small rubber rollers which
loosen each sheet from the one beneath, and push it forward until it is
caught by the folding apparatus. Man's mechanical ingenuity has given to
the machines of his invention something that seems almost like human
intelligence, and in the case of the folding machine, the action is so
regular and perfect that there seems to be no need of an attendant, save
to furnish a constant supply of sheets. The folding completed, cutting
machines are again brought into requisition, to cut and trim the sheets
to the size of folded note or letter-paper, which is the final operation
before they are sent out into the world on their mission of usefulness.
The finished paper may or may not have passed through the ruling and
folding process, but in either case it goes from the cutters to the
wrappers and packers, and then to the shipping-clerks, all of whom
perform the duties indicated by their names. The wonderful
transformation wrought by the magic wand of science and human invention
is complete, and what came into the factory as great bales of offensive
rags, disgusting to sight and smell, goes forth as delicate, beautiful,
perfected paper, redeemed from filth, and glorified into a high and
noble use. Purity and beauty have come from what was foul and
unwholesome; the highly useful has been summoned forth from the
seemingly useless; a product that is one of the essential factors in the
world's progress, and that promises to serve an ever-increasing purpose,
has been developed from a material that apparently held not the
slightest promise. Well might the _Boston News Letter_ of 1769 exclaim
in quaint old rhyme:
Rags are as beauties which concealèd lie,
But when in paper, charming to the eye!
Pray save your rags, new beauties to discover,
For of paper truly every one's a lover;
By the pen and press such knowledge is displayed
As would not exist if paper was not made.
And well may man pride himself on this achievement, this marvelous
transformation, which represents the fruitage of centuries of striving
and endeavor!
Up to this point the reference has been almost entirely to paper made
from rags, but radical improvements have been made, caused by the
introduction of wood pulp, and these are of such importance that the
account would not be complete without some mention of them. These
changes are mainly in the methods of manipulating the wood to obtain the
pulp, for when that is ready, the process from and including the
"washers" and "beaters," is very similar to that already described. All
papers, whether made from rags or wood, depend upon vegetable fiber for
their substance and fundamental base, and it is found that the different
fibers used in paper-making, when finally subdued, do not differ, in
fact, whether obtained from rags or from the tree growing in the forest.
In the latter case the raw wood is subjected to chemical treatment which
destroys all resinous and foreign matters, leaving merely the cellular
tissue, which, it is found, does not differ in substance from the cell
tissue obtained after treating rags. In either case this cellular
tissue, through the treatment to which the raw material is subjected,
becomes perfectly plastic or moldable, and while the paper made from one
differs slightly in certain characteristics from the paper made from the
other, they are nevertheless very similar, and it might be safe to
predict that further perfecting of processes will eventually make them
practically alike.
The woods used for this purpose are principally poplar and spruce, and
there are three classes of the wood pulp: (1) mechanical wood, (2) soda
process wood, and (3) sulphite wood pulp. The first method was invented
in Germany in 1844. The logs are hewn in the forest, roughly barked, and
shipped to the factory, where the first operation is to cut them up by
steam saws into blocks about two feet in length. Any bark that may still
cling to the log is removed by a rapidly revolving corrugated wheel of
steel, while the larger blocks are split by a steam splitter. The next
stage of their journey takes these blocks to a great millstone set
perpendicularly instead of horizontally. Here a very strong and
ingenious machine receives one block at a time, and with an
automatically elastic pressure holds it sidewise against the millstone,
which, like the mills of the gods, "grinds exceeding fine," and with the
aid of constantly flowing water rapidly reduces these blocks to a pulpy
form. This pulp is carried into tanks, from which it is passed between
rollers, which leave it in thick, damp sheets, which are folded up
evenly for shipment, or for storage for future use. If a paper-mill is
operated in connection with the pulp-mill, the wood pulp is not
necessarily rolled out in sheets, but is pumped directly from the tanks
to the beaters.
In the preparation of pulp by the other processes, the blocks are first
thrown into a chipping machine with great wheels, the short, slanting
knives of which quickly cut the blocks into small chips.
In the soda process, invented by M. Meliner in France in 1865, the chips
from spruce and poplar logs are boiled under pressure in a strong
solution of caustic soda.
When sulphite wood pulp is to be prepared, the chips are conveyed from
the chipper into hoppers in the upper part of the building. Here they
are thrown into great upright iron boilers or digesters charged with
lime-water and fed with the fumes of sulphur which is burned for the
purpose in a furnace adjoining the building and which thus forms acid
sulphide of lime. The sulphite process was originally invented by a
celebrated Philadelphia chemist, but was perfected in Europe.
The "cooking," or boiling, to which the wood is subjected in both the
soda and sulphite processes, effects a complete separation of all
resinous and foreign substances from the fine and true cell tissue, or
cellulose, which is left a pure fiber, ready for use as described. In
the case of all fibers, whether rag or wood, painstaking work counts,
and the excellence of the paper is largely dependent upon the time and
care given to the reduction of the pulp from the original raw material.
Chemical wood pulp of the best quality makes an excellent product, and
is largely used for both print and book paper; it is frequently mixed
with rag pulp, making a paper that can scarcely be distinguished from
that made entirely from fine rags, though it is not of the proper
firmness for the best flat or writing papers. All ordinary newspapers,
as well as some of the cheaper grades of book and wrapping paper, are
made entirely from wood, the sulphite or soda process supplying the
fiber, and ground wood being used as a filler. In the average newspaper
of to-day's issue, twenty-five per cent of sulphite fiber is sufficient
to carry seventy-five per cent of the ground wood filler. The value of
the idea is an economical one entirely, as the ground wood employed
costs less than any other of the component parts of a print-paper sheet.
The cylinder machine, to which reference was made earlier in the
chapter, was patented in 1809 by a prominent paper-maker of England, Mr.
John Dickinson. In this machine, a cylinder covered with wire cloth
revolves with its lower portion dipping into a vat of pulp, while by
suction a partial vacuum is maintained in the cylinder, causing the pulp
to cling to the wire until it is conveyed to a covered cylinder, which
takes it up and carries it forward in a manner similar to the system
already described. This machine is employed in making straw-board and
other heavy and cheap grades of paper.
Generous Mother Nature, who supplies man's wants in such bountiful
fashion, has furnished on her plains and in her forests an abundance of
material that may be transformed into this fine product of human
ingenuity. Esparto, a Spanish grass grown in South Africa, has entered
largely into the making of print-paper in England. Mixed with rags it
makes an excellent product, but the chemicals required to free it from
resin and gritty silica are expensive, while the cost of importation has
rendered its use in America impractical. Flax, hemp, manila, jute and
straw, and of course old paper that has been once used, are extensively
employed in this manufacture, the process beginning with the chemical
treatment and boiling that are found necessary in the manipulation of
rags. The successful use of these materials has met demands that would
not otherwise have been supplied. As a result, the price has been so
cheapened that the demand for paper has greatly increased, and its use
has been extended to many and various purposes.
Many additional items of interest might be described in connection with
the methods of manufacturing paper, but as this work is intended for the
general reader, rather than for the manufacturer, those wishing further
information are referred to technical works on the subject.
The best linen rags are used for the highest grades of writing and bond
papers, while ordinary note, letter, and flat papers are made from
cotton rags. In some mills, such as the government mill at Dalton,
Massachusetts, where the government paper is made for banknotes, and in
others where the finest ledger papers are manufactured, none but new,
clean rags are used. These come from the remnants left in the making of
linen goods. In the government mill where is made the paper for our
national currency, or "greenbacks," there is a special attachment on the
machine for introducing into the paper the silk threads that are always
to be seen in our paper money. This attachment is just above the "wire"
on the machine, and consists of a little conducting trough, through
which flows, from a receptacle near the machine, a stream of water
holding the silk threads in solution. The trough extends across the
machine, and is provided at intervals with openings through which the
short pieces of silk thread are automatically released, and sprinkled
continuously onto the web of pulp as it passes beneath. The paper is
thus distinguished, and infringement and possible counterfeiting are
made extremely difficult by the fact that the government absolutely
forbids the making of paper by others under a similar process, as well
as the production of any paper containing these silk threads. The laws
of the United States pertaining to anything that borders on infringement
of our various money issues, both metal and currency, are most rigid;
anything approaching a similarity of impression is prohibited, and a
cut, stamp, or impression of any character that approaches in its
appearance any money issue of our government is considered a violation
of the law against counterfeiting, and is dealt with severely. The
government takes the same uncompromising position in regard to the
fabrics used in printing its paper-money issues, and it will be quickly
seen that the silk thread process described above it is so great a
variation from anything required in the mercantile world that it would
be difficult to produce a paper at all similar without an ulterior
purpose being at once apparent. For this reason the silk thread
interspersion is in reality a very effective medium in preventing
counterfeiting, not only on account of its peculiar appearance but also
because of the elaborate methods necessary in its production.
In those mills making the finest grades of paper, much of the process of
thrashing, beating, dusting, and cleaning necessary in the ordinary mill
is omitted. The cleanliness and brightness which are reached only at the
"washer" and "beater" engines in the process of manufacturing the lower
grades of paper from cheaper rags, prevail at every step in these higher
grade mills.
One of the first requisites in making good paper, especially the better
grades, is an abundance of pure water, and spring-water, where
available, is preferred.
The effort has been made in the description given to cover the process
of making paper from the crudest rags. In enumerating the several kinds
of paper in another chapter, brief reference will be made to the varying
methods required in their manufacture. In this chapter, no attempt has
been made to cover more than the principal divisions or varieties of
paper--writing, print, and wrapping papers.
The United States, with characteristic enterprise, leads the world in
paper-making, supplying about one-third of all that is used on the
globe. The city of Holyoke, in Massachusetts, is the greatest paper
center in the world, turning out each working-day some two hundred tons
of paper, nearly one-half of which is "tub-sized," "loft-dried"
writings. The region in the vicinity of Holyoke is dotted with
paper-mills, and within a few miles of the city is made about one-half
of all the "loft-dried" writings produced in the United States. The tiny
acorn planted two centuries ago has waxed with the years, gaining
strength and vigor with the increasing strength of the nation, till now
it has become a giant oak, whose branches extend to the lands beyond the
seas.