Cellulose.–Action of Acids on Cellulose.–Physical
Characteristics of Cellulose.–Micrographic Examination of
Vegetable Fibres.–Determination of Cellulose.–Recognition of
Vegetable Fibres by the Microscope.
=Cellulose.=–Vegetable fibre, when deprived of all incrusting or
cementing matters of a resinous or gummy nature, presents to us the
true fibre, or _cellulose_, which constitutes the essential basis
of all manufactured paper. Fine linen and cotton are almost pure
cellulose, from the fact that the associated vegetable substances
have been removed by the treatment the fibres were subjected to in
the process of their manufacture; pure white, unsized, and unloaded
paper may also be considered as pure cellulose from the same cause.
Viewed as a chemical substance, cellulose is white, translucent,
and somewhat heavier than water. It is tasteless, inodorous,
absolutely innutritious, and is insoluble in water, alcohol, and
oils. Dilute acids and alkalies, even when hot, scarcely affect
it. By prolonged boiling in dilute acids, however, cellulose
undergoes a gradual change, being converted into _hydro-cellulose_.
It is also affected by boiling water alone, especially under high
pressure, if boiled for a lengthened period. Without going deeply
into the chemical properties of cellulose, which would be more
interesting to the chemist than to the paper manufacturer, a few
data respecting the action of certain chemical substances upon
cellulose will, it is hoped, be found useful from a practical point
of view, especially at the present day, when so many new methods of
treating vegetable fibres are being introduced.
=Action of Acids on Cellulose.=–When concentrated sulphuric acid
is added very gradually to about half its weight of linen rags
cut into small shreds, or strips of unsized paper, and contained
in a glass vessel, with constant stirring, the fibres gradually
swell up and disappear, without the evolution of any gas, and a
tenacious mucilage is formed which is entirely soluble in water.
If, after a few hours, the mixture be diluted with water, the
acid neutralised with chalk, and after filtration, any excess
of lime thrown down by cautiously adding a solution of oxalic
acid, the liquid yields, after a second filtration and the
addition of alcohol in considerable excess, a gummy mass which
possesses all the characters of _dextrin_. If instead of at once
saturating the diluted acid with chalk, we boil it for four or
five hours, the _dextrin_ is entirely converted into grape sugar
(_glucose_), which, by the addition of chalk and filtration, as
before, and evaporation at a gentle heat to the consistence of
a syrup, will, after repose for a few days, furnish a concrete
mass of crystallised sugar. Cotton, linen, or unsized paper, thus
treated, yield fully their own weight of gum and one-sixth of
their weight of grape sugar. Pure cellulose is readily attacked
by, and soon becomes dissolved in, a solution of oxide of copper
in ammonia (_cuprammonium_), and may again be precipitated in
colourless flakes by the addition of an excess of hydrochloric
acid, and afterwards filtering and washing the precipitate.
Concentrated boiling hydrochloric acid converts cellulose into a
fine powder, without, however, altering its composition, while
strong nitric acid forms nitro-substitution products of various
degrees, according to the strength of the acid employed. “Chlorine
gas passed into water in which cellulose is suspended rapidly
oxidises and destroys it, and the same effect takes place when
hypochlorites, such as hypochlorite of calcium, or bleaching
liquors, are gently treated with it. It is not, therefore, the
cellulose itself which we want the bleaching liquor to operate
upon, but only the colouring matters associated with it, and care
must be taken to secure that the action intended for the extraneous
substances alone does not extend to the fibre itself. Caustic
potash affects but slightly cellulose in the form in which we have
to do it, but in certain less compact conditions these agents
decompose or destroy it.”–_Arnot._
=Physical Characteristics of Cellulose.=–“The physical condition
of cellulose,” says Mr. Arnot, “after it has been freed from
extraneous matters by boiling, bleaching, and washing, is of great
importance to the manufacturer. Some fibres are short, hard,
and of polished exterior, while others are long, flexible, and
barbed, the former, it is scarcely necessary to say, yielding
but indifferent papers, easily broken and torn, while the papers
produced from the latter class of fibres are possessed of a great
degree of strength and flexibility. Fibres from straw, and from
many varieties of wood, may be taken as representatives of the
former class, those from hemp and flax affording good illustrations
of the latter. There are, of course, between these extremes all
degrees and combinations of the various characteristics indicated.
It will be readily understood that hard, acicular fibres do not
felt well, there being no intertwining or adhesion of the various
particles, and the paper produced is friable. On the other hand,
long, flexible, elastic fibres, even though comparatively smooth
in their exterior, intertwine readily, and felt into a strong
tough sheet…. Cotton fibre is long and tubular, and has this
peculiarity, that when dry the tubes collapse and twist on their
axes, this property greatly assisting the adhesion of the particles
in the process of paper-making. In the process of dyeing cotton,
the colouring matter is absorbed into the tubes, and is, as will
be readily appreciated, difficult of removal therefrom. Papers made
exclusively of cotton fibre are strong and flexible, but have a
certain sponginess about them which papers made from linen do not
Linen–the cellulose of the flax-plant–before it reaches the hands
of the paper-maker has been subjected to certain processes of
steeping or _retting_, and also subsequent boilings and bleachings,
by which the extraneous matters have been removed, and it therefore
requires but little chemical treatment at his hands. “Linen fibre,”
Arnot further observes, “is like cotton, tubular, but the walls of
the tubes are somewhat thicker, and are jointed or notched like a
cane or rush; the notches assist greatly in the adhesion of the
fibres one to another. This fibre possesses the other valuable
properties of length, strength, and flexibility, and the latter
property is increased when the walls of the tubes are crushed
together under the action of the beating-engine.” From this fibre
a very strong, compactly felted paper is made; indeed, no better
material than this can be had for the production of a first-class
paper. Ropes, coarse bags, and suchlike are made from hemp, the
cellulose or fibre of which is not unlike that of flax, only it is
of a stronger, coarser nature. Manilla yields the strongest of
all fibres. Jute, which is the fibre or inside bark of an Indian
plant (_Corchorus capsularis_), yields a strong fibre, but is very
difficult to bleach white. Esparto fibre holds an intermediate
place between the fibres just described and those of wood and
straw…. The fibre of straw is short, pointed, and polished, and
cannot of itself make a strong paper. The nature of wood fibre
depends, as may readily be supposed, upon the nature of the wood
itself. Yellow pine, for example, yields a fibre long, soft, and
flexible, in fact very like cotton; while oak and many other woods
yield short circular fibres which, unless perfectly free from
extraneous matters, possess no flexibility, and in any case are not
=Micrographic Examination of Vegetable Fibres.=–The importance
of the microscope in the examination of the various fibres that
are employed in paper manufacture will be readily evident from
the delicate nature of the cellulose to be obtained therefrom.
Amongst others M. Girard has determined, by this method of
examination, the qualities which fibres ought to possess to suit
the requirements of the manufacturer. He states that absolute
length is not of much importance, but that the fibre should be
slender and elastic, and possess the property of turning upon
itself with facility. Tenacity is of but secondary importance, for
when paper is torn the fibres scarcely ever break. The principal
fibres employed in paper-making are divided into the following
1. _Round, ribbed fibres_, as hemp and flax.
2. _Smooth_, or _feebly-ribbed fibres_, as esparto, jute,
phormium (New Zealand flax), dwarf palm, hop, and sugar-cane.
3. _Fibro-cellular substances_, as the pulp obtained from the
straw of wheat and rye by the action of caustic ley.
4. _Flat fibres_, as cotton, and those obtained by the action of
caustic ley upon wood.
5. _Imperfect substances_, as the pulp obtained from sawdust.
In this class may also be included the fibre of the so-called
“mechanical wood pulp.”
=Determination of Cellulose.= For the determination of cellulose
in wood and other vegetable fibres to be used in paper-making
Müller recommends the following processes: 5 grammes weight
of the finely-divided substance is boiled four or five times in
water, using 100 cubic centimètres each time. The residue is
then dried at 100° C. (212° Fahr.), weighed, and exhausted with
a mixture of equal measures of benzine and strong alcohol, to
remove fat, wax, resin, &c. The residue is again dried and boiled
several times in water, to every 100 c.c. of which 1 c.c. of strong
ammonia has been added. This treatment removes colouring matter and
pectous substances. The residue is further bruised in a mortar
if necessary, and is then treated in a closed bottle with 250 c.c.
of water, and 20 c.c. of bromine water containing 4 c.c. of bromine
to the litre. In the case of the purer bark-fibres, such as flax
and hemp, the yellow colour of the liquid only slowly disappears,
but with straw and woods decolorisation occurs in a few minutes,
and when this takes place more bromine water is added, this being
repeated until the yellow colour remains, and bromine can be
detected in the liquid after twelve hours. The liquid is then
filtered, and the residue washed with water and heated to boiling
with a litre of water containing 5 c.c. of strong ammonia. The
liquid and tissue are usually coloured brown by this treatment. The
undissolved matter is filtered off, washed, and again treated with
bromine water. When the action seems complete the residue is again
heated with ammoniacal water. This second treatment is sufficient
with the purer fibres, but the operation must be repeated as often
as the residue imparts a brownish tint to the alkaline liquid. The
cellulose is thus obtained as a pure white body; it is washed with
water, and then with boiling alcohol, after which it may be dried
at 100° C. (212° Fahr.) and weighed.
=Recognition of Vegetable Fibres by the Microscope.=–From
Mr. Allen’s admirable and useful work on “Commercial Organic
Analysis” we make the following extracts, but must refer the
reader to the work named for fuller information upon this important
consideration of the subject. In examining fibres under the
microscope, it is recommended that the tissues should be cut up
with sharp scissors, placed on a glass slide, moistened with water,
and covered with a piece of thin glass. Under these conditions:–
_Filaments of Cotton_ appear as transparent tubes, flattened and
twisted round their axes, and tapering off to a closed point at
each end. A section of the filament somewhat resembles the figure
8, the tube, originally cylindrical, having collapsed most in the
middle, forming semi-tubes on each side, which give the fibre,
when viewed in certain lights, the appearance of a flat ribbon,
with the hem of the border at each edge. The twisted, or corkscrew
form of the dried filament of cotton distinguishes it from all
other vegetable fibres, and is characteristic of the matured pod,
M. Bauer having found that the fibres of the unripe seed are
simply untwisted cylindrical tubes, which never twist afterwards
if separated from the plant. The matured fibres always collapse
in the middle as described, and undergo no change in this respect
when passing through all the various operations to which cotton is
subject, from spinning to its conversion into pulp for paper-making.
_Linen_, _or Flax Fibre_, under the microscope, appears as hollow
tubes, open at both ends, the fibres being smooth, and the inner
tube very narrow, and joints, or _septa_, appear at intervals,
but are not furnished with hairy appendages as is the case with
hemp. When flax fibre is immersed in a boiling solution of equal
parts of caustic potash and water for about a minute, then removed
and pressed between folds of filter-paper, it assumes a dark yellow
colour, whilst cotton under the same treatment remains white or
becomes very bright yellow. When flax, or a tissue made from it,
is immersed in oil, and then well pressed to remove excess of
the liquid, it remains translucent, while cotton, under the same
conditions, becomes opaque.
_New Zealand Flax_ (_Phormium tenax_) may be distinguished from
ordinary flax or hemp by a reddish colour produced on immersing
it first in a strong chlorine water, and then in ammonia. In
machine-dressed New Zealand flax the bundles are translucent and
irregularly covered with tissue; spiral fibres can be detected in
the bundles, but less numerous than in Sizal. In Maori-prepared
phormium the bundles are almost wholly free from tissue, while
there are no spiral fibres.
_Hemp Fibre_ resembles flax, and exhibits small hairy appendages at
the joints. In Manilla hemp the bundles are oval, nearly opaque,
and surrounded by a considerable quantity of dried-up cellular
tissue composed of rectangular cells. The bundles are smooth, very
few detached ultimate fibres are seen, and no spiral tissue.
_Sizal_, _or Sisal Hemp_ (_Agave Americana_), forms oval fibrous
bundles surrounded by cellular tissue, a few smooth ultimate fibres
projecting from the bundles; is more translucent than Manilla, and
a large quantity of spiral fibres are mixed up in the bundles.
_Jute Fibre_ appears under the microscope as bundles of tendrils,
each being a cylinder, with irregular thickened walls. The
bundles offer a smooth cylindrical surface, to which the silky
lustre of jute is due, and which is much increased by bleaching.
By the action of hypochlorite of soda the bundles of fibres
can be disintegrated, so that the single fibres can be readily
distinguished under the microscope. Jute is coloured a deeper
yellow by sulphate of aniline than is any other fibre.
In former days the only materials employed for the manufacture of
paper were linen and cotton rags, flax and hemp waste, and some
few other fibre-yielding materials. The reduction of the excise
duty, however, from 3d. to 1½d. per lb., which took effect in the
first year of Her Majesty’s reign–namely, in 1837–created a
greatly increased demand for paper, and caused much anxiety amongst
manufacturers lest the supply of rags should prove inadequate
to their requirements. Again, in the year 1861 the excise duty
was totally abolished, from which period an enormously increased
demand for paper, and consequently paper material, was created
by the establishment of a vast number of daily and weekly papers
and journals in all parts of the kingdom, besides reprints of
standard and other works in a cheap form, the copyright of which
had expired. It is not too much to say, that unless other materials
than those employed before the repeal of the paper duty had been
discovered, the abolition of the impost would have proved but of
little service to the public at large. Beneficent Nature, however,
has gradually, but surely and amply, supplied our needs through the
instrumentality of man’s restless activity and perseverance.
The following list comprises many of the substances from which
cellulose, or vegetable fibre, can be separated for the purposes of
paper-making with advantage; but the vegetable kingdom furnishes
in addition a vast number of plants and vegetables which may also
be used with the same object. We have seen voluminous lists of
fibre-yielding materials which have been suggested as suitable
for paper-making, but since the greater portion of them are never
likely to be applied to such a purpose, we consider the time wasted
in proposing them. It is true that the stalks of the cabbage tribe,
for example, would be available for the sake of their fibre, but
we should imagine that no grower of ordinary intelligence would
deprive his ground of the nourishment such waste is capable of
_returning to the soil_, by its employment as manure, to furnish
a material for paper-making. Again, we have seen blackberries,
and even the pollen (!) of plants included in a list of paper
materials, but fortunately the manufacturer is never likely to be
reduced to such extremities as to be compelled to use materials of
Flax waste, etc.
Jute waste, etc.
Straw of wheat, etc.
Rushes of various kinds.
New Zealand flax.
Maize stems, husks, etc.
Woods of various kinds, especially white non-resinous woods, as
poplar, willow, etc.
Wood shavings, sawdust, and chips.
Barks of various trees, especially of the paper mulberry.
Twigs of common broom and heather.
Mustard stems after threshing.
Beetroot refuse from sugar works.
Megass, or “cane trash”–refuse of the sugar cane after the juice
has been extracted.
Dyers’ wood waste.
Old bast matting.
Binders’ clippings, etc.
Sea grass (_Zostera marina_).
Fibrous waste resulting from pharmaceutical preparations.
Silk cocoon waste.
Tarpaulin. Etc., etc.
=Rags.=–Linen and cotton rags are imported into Great Britain
from almost all the countries of Europe, and even from the distant
states of South America, British South Africa, and Australasia. The
greater proportion, however, come from Germany. The rags collected
in England chiefly pass through the hands of wholesale merchants
established in London, Liverpool, Manchester, and Bristol, and
these are sorted to a certain extent before they are sent to the
paper-mills. By this rough sorting, which does not include either
cleansing or disinfecting, certain kinds of rags which would be
useless to the paper-maker are separated and sold as manure.
Woollen rags are not usually mixed with cotton rags, but are
generally kept apart to be converted into “shoddy.” The importance
of disinfecting rags before they pass through the hands of the
workpeople employed at the paper-mills cannot be over-estimated,
and it is the duty of every Government to see that this is
effectually carried out, not only at such times when cholera and
other epidemics are known to be rife in certain countries from
which rags may be imported, but at all times, since there is no
greater source of danger to the health of communities than in the
diffusion of old linen and cotton garments, or pieces, which are
largely contributed by the dwellers in the slums of crowded cities.
Respecting the disinfecting of rags, Davis thus explains the
precautions taken in the United States to guard against the dangers
of infection from rags coming from foreign or other sources.
“When cholera, or other infectious or contagious diseases exist
in foreign countries, or in portions of the United States, the
health officers in charge of the various quarantines in this
country require that rags from countries and districts in which
such diseases are prevalent shall be thoroughly disinfected before
they are allowed to pass their stations. Rags shipped to London,
Hull, Liverpool, Italian, or other ports, and re-shipped from such
ports to the United States, are usually subjected to the same rule
as if shipped direct from the ports of the country in which such
diseases prevail. It is usually requisite that the disinfection
shall be made at the storehouse in the port of shipment, by boiling
the rags several hours under a proper degree of pressure, or in a
tightly-closed vessel, or disinfected with sulphurous acid, which
is evolved by burning at least two pounds of roll sulphur to every
ten cubic feet of room space, the apartment being kept closed
for several hours after the rags are thus treated. Disinfection
by boiling the rags is usually considered to be the best method.
In the case of rags imported from India, Egypt, Spain, and other
foreign countries where cholera is liable to become epidemic, it
is especially desirable that some efficient, rapid, and thorough
process of disinfecting should be devised. In order to meet the
quarantine requirements, it must be thorough and certain in its
action, and in order that the lives of the workmen and of others
in the vicinity may not be endangered by the liberating of active
disease-germs, or exposure of decaying and deleterious matters, and
that the delay, trouble, and exposure of unbaling and rebaling may
be avoided, it must be capable of use upon the rags while in the
bale, and of doing its work rapidly when so used.”
=Disinfecting Machine.=–To facilitate the disinfecting of rags
while in the bale, Messrs. Parker and Blackman devised a machine,
for which they obtained a patent in 1884, from which the following
abstract is taken.
Formerly rags and other fibrous materials were disinfected by being
subjected to germ-destroying gases or liquids in enclosed chambers,
but in order to render the disinfecting process effectual, it was
found necessary to treat the material in a loose or separated
state, no successful method having been adopted for disinfecting
the materials while in the bale. “This unbaling and loosening or
spreading of the undisinfected material is absolutely unsafe and
dangerous to the workmen, or to those in the vicinity, because of
the consequent setting free of the disease germs, and the exposing
of any decaying or deleterious matters which may be held in the
material while it is compressed in the bale. The unbaling and
necessary rebaling of the material for transportation also involves
much trouble and expense and loss of time. Large and cumbrous
apparatus is also necessary to treat large quantities of material
loosened or opened out as heretofore.”
[Illustration: Fig. 1.]
It is specially necessary that rags coming from Egypt and other
foreign countries should be thoroughly disinfected by some rapid
and effectual means, which, while not endangering the health of
workmen employed in this somewhat hazardous task, will fully meet
all quarantine requirements. The apparatus devised by Messrs.
Parker and Blackman, an abridged description of which is given
below, will probably accomplish this much-desired object.
[Illustration: Fig. 2.]
In the illustration, Fig. 1, A is the disinfecting chamber. At one
end is an opening A^1, and a door B, hinged at its lower edge and
adapted to be swung up, so as to close the opening tightly. For
supporting and carrying the bale C of material to be placed in the
chamber is a carriage C^1, consisting of a platform supported upon
wheels or castors _c c_. While the carriage is wholly within
the chamber A, as shown in Fig. 2, these wheels rest upon the
false bottom B^2; when the carriage is rolled back and out of the
chamber, as shown in Fig. 1, they roll upon the upper face of door
B swung down. The carriage is provided with a clamping device D
to hold the bale firmly and immovably. To cause the carriage to
move into and out of the chamber, the inventors provide upon the
under side of the platform a fixed sleeve E, interiorly threaded to
fit the screw E^1, journalled at one end near the opening in the
chamber end in a stationary block E^2 fixed upon the false bottom
B^2. From this end the screw extends along under the carriage
through the screw sleeve and to the other end of the chamber. A
collar _e_^2 on the screw bears against the inner end of this
journal-bearing, and upon the end of the shank _e_ bearing against
the other end of the journal is fixed a pinion F, which is to be
driven in either direction as desired. Above this journal-bearing
is a series of similar bearings (five being shown), G G, passing
through the wall of the chamber. Of these the middle one is in
a line with the centre of the bale, supported and held on the
carriage. The others are arranged at the corners of a square.
Journalled in these bearings are the hollow shanks H H of the
hollow screws I I pointed at I^1 I^1. Each screw is perforated,
_i i_, between the threads _i_^1 _i_^1 from the fixed collar K K.
Upon the tubular shanks H H of the screws are fixed the gear-wheels
L L. At a short distance from the end of the chamber, A is the
hollow chamber or receptacle M, into which is to be forced the
disinfectant liquid or gas. The tubular shanks H H of the screws
project through the wall M, passing through stuffing-boxes _m m_,
and their bores communicate with the interior of the chamber, the
shank of the middle screw being continued through the opposite
wall and a stuffing-box, its solid or projecting end being provided
with two fixed pulleys, N N, and a loose pulley O. When a gaseous
disinfectant is used, it can be forced by any desired means through
the pipe S into the chamber. Where a liquid disinfectant is used,
an elevated tank R containing the fluid may be used. As most
fibrous materials, and especially rags, are baled so as to be in
layers, it is preferable so to place the bale upon the carriage
that the perforated screws may penetrate the material at right
angles to the layers by which the gas or liquid issuing through the
holes in the screws passes in all directions throughout the mass
within the bale.
In the upper part of chamber A are perforated shelves V V, upon
which, if desired, the material can be spread out and subjected to
disinfecting gas or vapour. On the top of the chamber is a tank
W nearly filled with disinfecting liquid. A passage W^1 extends
from upper part of the chamber up into the tank above the level of
the liquid therein, and is then carried at its end down below the
surface of the liquid. At its other end the tank is provided at its
top with a discharge opening X and a suitable pipe X^1, forming a
continuation of the opening; by this means all foul and deleterious
vapours or gases passing out of the closed chamber A through the
passage W must pass through the disinfecting liquid in the tank
before escaping through the opening X and stack X^1 into the air,
and are thus rendered harmless.
When a sufficient amount of the disinfectant has been forced into
and through the bale, the disinfectant is turned off, and cold dry
air can be forced through chamber M, and out through the nozzles
and bale, whereby the material within the bale becomes cooled and
dried, and all the foul air from the chamber A driven out, so that
it may be opened and entered with safety. Any suitable disinfectant
may be used with this apparatus, as, for example, sulphurous acid,
in gas or solution, superheated steam, carbolic acid, or any
solution or vapour containing chlorine.
=Straw.=–Very large quantities of this material are used in the
manufacture of paper, but more especially for newspapers, the straw
from wheat and oats being mostly employed. Although the percentage
of cellulose in straw is about equal to that of esparto, the severe
treatment it requires to effectually remove the silicious coating
by which the fibre is protected, and to render the knots amenable
to the action of the bleach, greatly reduces the yield of finished
pulp. Many processes have been introduced for the treatment of
straw for paper-making, but the most successful of them appear to
be modifications of a process introduced in 1853 by MM. Coupier and
=Esparto Grass.=–This important fibrous material is largely
imported from Algeria, Spain, and other countries, and constitutes
one of the most valuable fibre-yielding materials with which the
manufacturer has to deal. Some idea of the amount of esparto and
other fibres which find their way to our shores may be gleaned
from the fact that while the import of cotton and linen rags in
the year 1884 was 36,233 tons, of the value of £487,866, that of
esparto and other fibres amounted to 184,005 tons, of the value of
=Wood.=–As a paper-making material, the fibre obtained from
various kinds of wood now holds an important position, since
the sources of supply are practically inexhaustible. The first
practical process for manufacturing pulp from wood fibre was
perfected and introduced by the author’s father, the late Mr.
Charles Watt, who, in conjunction with Mr. H. Burgess, obtained
a patent for the invention on August 19th, 1853. The process was
afterwards publicly exhibited at a small works on the Regent’s
Canal, when the Earl of Derby (then Lord Stanley), many scientific
men and representatives of the press, were present, and expressed
themselves well satisfied with its success. Specimens of the wood
paper, including a copy of the _Weekly Times_ printed thereon,
were exhibited, as also some water-colour drawings which had
been produced upon paper made from wood pulp. Failing to get the
process taken up in England, an American patent was applied for and
obtained in 1854, which was subsequently purchased; but with the
exception of an instalment, the purchase-money was never paid to
the inventor! Thus the process “got” into other hands, the original
inventor alone being unbenefited by it.
It has been repeatedly stated, no doubt unwittingly, that a
person named Houghton first introduced the wood paper process into
this country; but considering that his patent was not obtained
until 1857, or four years after the process above referred to was
patented and publicly exhibited in England, it will be seen that
the statement is absolutely without foundation. The first knowledge
Mr. Houghton received concerning wood as a paper-making material
was from the author’s father, and he (Mr. Houghton), in conjunction
with Mr. Burgess, introduced the Watt and Burgess process into
America in the year 1854. These are the facts.
=Bamboo= (_Bambusa vulgaris_).–The leaves and fresh-cut stems of
this plant are used for paper material, but require to pass through
a preliminary process of crushing, which is effected by suitable
rolls, the second series of crushing rolls being grooved or
channelled to split or divide the material, after which the stems
are cut to suitable lengths for boiling.
=Paper Mulberry= (_Broussonetia papyrifera_).–The inner bark of
this tree, and also some other basts, have long been used by the
Japanese and Chinese in the manufacture of paper of great strength,
but of extreme delicacy.