Of all the fibre-yielding plants known to botanical science there
is not one so well calculated to meet the pressing requirements of
the Paper-trade as "BAMBOO," both as regards facility and economy
of production, as well as the quality of the "_Paper-Stock_" which
can be manufactured therefrom: grown under favourable conditions of
climate and soil, there is no plant which will give so heavy a crop of
available fibre to the acre, no plant which requires so little care for
its cultivation and continuous production.
The rapidity of the growth of "BAMBOO" is unequalled. At Gehzireh,
the gardens of the Khedive of Egypt at Cairo, it has been known
to grow nine inches in a single night. At Syon House, the Duke of
Northumberland's, stems of "_Bambusa Gigantea_" have attained the
height of 60 feet in 12 weeks; and I have made "_Paper-Stock_" from a
stem of "_Bambusa Vulgaris_," sent me by Dr. Hooker, from the Royal
Botanical Gardens at Kew, which, as measured by the gardener in the
Palm-house, grew at the rate of three feet in a single week; at
Chatsworth, the Duke of Devonshire's, this same variety (the "_Bambusa
Vulgaris_") has attained the height of 40 feet in 40 days.
Throughout the East Indies the "Bamboo" flourishes, forming indeed
in many districts impenetrable jungles. It grows abundantly also in
the West Indies, in Central and South America, the Brazils, in Africa
and Asia; in China especially, and in Japan, the plant is indigenous,
and the natives cultivate it carefully, employing it for almost every
article of convenience and luxury; in fact, wherever heat and moisture
exist, some species of the "Bamboo" will be found, or may be readily
cultivated.
Attempts have from time to time been made in England, and elsewhere,
to obtain from the "BAMBOO" "_Half-stuff_" or "_Pulp_" suitable for
the manufacture of paper, and paper indeed has been made therefrom,
but hitherto these attempts have neither industrially nor commercially
attained successful results, and for the following reasons.
Hitherto the "BAMBOO" has been collected and treated in a condition
more or less of maturity, or without regard to its age; and when the
plant has attained its full growth the woody fibre is extremely dense
and indurated; when old, indeed, the exterior portion of the stem of
many varieties of the plant becomes so hard and silicious that it will,
like flint, strike fire with steel.
Owing to the presence of this large quantity of silica, and the extreme
hardness of the stem when developed and matured, it has been found by
all those who have hitherto experimentally treated "BAMBOO" that the
only possible means of converting it into _Pulp_ for Paper-making, has
been to subject it to long-continued boiling, or digesting, in very
strong solutions of caustic alkali, at an elevated temperature--in
other words, at or under a pressure of ten to eleven atmospheres
(150 to 160 lb. pressure per square inch)--by which means a _Pulp_
has certainly been produced, but at a great cost, and the danger and
practical difficulties of working under such high pressure, have
deterred further progress in this direction.
I have found that when the stems of "Bamboo," are cut down at an early
stage of their growth, when the plant is full of sap, and before the
cellulose or cellular tissue, and the lignine have become indurated,
and silica deposited; while, in fact, so to speak, the plant may be
termed a succulent vegetable, and before it has become converted into
wood, that a very mild system of treatment in successive weak alkaline
baths, at atmospheric pressure only, suffices to decompose and render
soluble the mucilaginous and other extractive compounds combined
naturally with the fibrous tissue of the plant, so that they may be
readily eliminated, or separated therefrom, by subsequent washing,
leaving the residuary fibres pure and free.
A comparative illustration of the transitional stage of growth above
referred to, showing the conversion of succulent vegetable fibrous
tissue, into harsh woody fibre, may be remarked with "Asparagus,"
the young and green stems of which, are used as a delicacy for the
table, a few weeks further growth converting them into hard woody
fibre, which no amount of boiling would, or could, render palatable;
the "Asparagus," indeed, has its parallel in the "_Bambusa Edulis_," a
variety of "BAMBOO," the young stems of which are eaten and considered
very nourishing.
The "BAMBOO," being an _endogenous_ plant, (that is to say, growing
from inside) composed mainly of fibrous tissue, combined with the
ordinary sappy and other extractive matter common to all vegetable
growth, the stems do not require the elaborate preparatory manipulation
which is necessary to separate the fibrous, from the extraneous and
woody matter, which in _exogenous_ plants (i. e. growing from, or on
the outside) must be removed, as it is only the true fibre which is
useable for Textile Manufactures.
Such plants known to commerce as "FLAX," "HEMP," "JUTE," "RHEA," &c.
&c., after having become mature, and being dried, have to undergo a
process of retting, or steeping, followed by scutching and heckling, in
order to separate the ultimate fibres from the woody stem and bark to
which, while in their normal condition, they are attached.
The cost therefore, of producing merchantable fibre from this class of
plants is very considerable, and the produce or yield of fibre, to the
plant cultivated, very small, that of "FLAX" being computed at from 5
to 6 cwt., "HEMP" 7 cwt., and "JUTE" 5 to 6 cwt. per acre, "COTTON"
being much less; "BAMBOO," as I will presently show, producing tons as
compared with cwts. of the foregoing, and, be it noted, with far less
cost for cultivation, and the subsequent preparation of the fibre.
The stems of the "BAMBOO," cut young, as I propose to use them,
contain from 60 to 75 per cent. of moisture; it will be obvious,
therefore, that to ensure a regular and continuous supply, under
economical conditions, to a central factory for the manufacture of
"_Paper-Stock_," plantations would have to be formed contiguous
thereto, as practised with "SUGAR CANE," or in a similar manner to
Osier beds, in England.
I have mentioned the latter, as in order to stimulate a rapid, aqueous,
and sappy growth, as also to provide for the dry seasons common to hot
countries, a system of irrigation would be necessary, such a system
indeed being at present practised with the SUGAR CANE, in Egypt, Spain,
and elsewhere.
With plantations of "Sugar Cane," to which plant the "BAMBOO" somewhat
assimilates in character and growth, it is necessary, in order to
ripen the canes and develop saccharine, to allow free ventilation to
the growing plant, and thus the ground is not fully occupied; this
would not be the case with "BAMBOO," which should be planted and grown
closely together to favour the stems shooting upwards, as practised
with "HEMP" and "FLAX," where fine staple of fibre is desired.
By following such a system, the stools or roots once established, a
systematical and regular cropping, or cutting, would ensue, the stems
being all cut down simultaneously, by sections or beds, in regular
succession, numerous croppings annually would thus be obtained, and
when necessary, fresh beds would be formed, the older growth being
available for fuel for the manufactory.
The Sugar Cane from the time of planting, to cutting, takes from nine
to twelve months to grow and mature; but even thus grown, the produce
of canes (ready dressed for the mill) generally ranges from 30 to 35
tons to the acre, it sometimes exceeds 40 tons; allowing several crops
or cuttings annually for the "BAMBOO," it may fairly be assumed that at
least this latter quantity would be obtained per acre.
Allowing 208 feet square to represent one acre; divided into twelve
beds, each 96 × 26 feet, with twelve paths 96´ × 8´ 8´´ wide, and one
intersecting road 208 × 16 feet wide, leaves a space for planting equal
to 2496 feet, or 29,952 feet in the twelve beds; allowing the stems to
be 2 feet apart, and say only 12 feet high, we have 7488 stems, which
at 12 lb. each = 40 tons per acre.
The stem of the "_Bambusa Vulgaris_" before mentioned, grown in
the Palm-house at Kew, was of an average size, 10 to 11 inches
circumference, and weighed green 1-1/2 lb. per foot run; and although
no doubt by denser growth, induced by frequent cropping, the stems
even of the larger varieties of "BAMBOO" would decrease in size, still
an equal tonnage to the acre would be produced, with longer joints or
internodes, and a finer staple of fibre.
The stems of the "BAMBOO" (_taken as dry_) treated by my process, will
yield 60 per cent. of unbleached _Fibrous_ "_Paper-Stock_," baled up
in merchantable condition; assuming therefore an annual cropping of 40
tons, green stems, which will lose 75 per cent. moisture in drying, we
have 10 tons dry stems per acre; these at 60 per cent. yield, will give
6 tons per acre of "_Paper-Stock_," an enormous product as compared
with any other fibrous material with which I am acquainted.
Allowing the plantation to be credited at the rate of 5_s._ per ton,
for the green stems, delivered to the central factory, and 40 tons to
be produced per acre, we have the sum of 10_l._ per acre to cover all
charges; once, however, the plantation formed, but little cost in the
way of cultivation need be incurred. The main outlay would be for rent,
irrigation, and cutting, and carrying to the manufactory.
I may here remark that I propose where possible, to return to the
_Plantation_, mixed with the water employed for irrigation, the
mucilaginous and other extractive constituents, or matters, (amounting
to 40 per cent.) abstracted from the stems during the process of
manufacturing the "_Paper-Stock_," as Manure, thus maintaining
fertilization to the growing plant.
DETAILS OF MY SYSTEM OF TREATING "BAMBOO" FOR THE MANUFACTURE OF
FIBROUS "_Paper-Stock_."
An essential point in my system for treating "BAMBOO" to produce
therefrom fibrous "_Paper-Stock_," consists in operating upon the stems
of the plant when young, and preferably when fresh, as, and when, cut
and collected.
Brought therefore to a central factory in this condition, the stems
are passed through heavy crushing rolls, in order to split and flatten
them, and at the same time crush, or smash, the knots, or nodes. The
stems thus flattened, are then passed through a second series of
rolls, which are channelled, or grooved, in order further to split, or
partially divide them longitudinally into strips, or ribbons; these
being cut transversely, into convenient lengths by a guillotine knife
or shears, are delivered by a carrier, or automatic feeder, direct to
the boiling pans, or elsewhere, as desired.
As the stems when fresh and green, contain from 60 to 75 per cent.
of sappy and mucilaginous matter, much of this is expressed by the
crushing, while at the same time the fibrous mass, being partially
disintegrated, is thus more readily acted upon in the succeeding
processes.
If desired, the crushed stems may be dried and stored; such drying,
however, must be very carefully conducted and watched to avoid
destructive fermentation.
I have in the preceding "Remarks" referred to "FLAX," "HEMP,"
"JUTE," and similar FIBRES known to commerce, such fibres being
imported into this country in their prepared condition, suitable for
Textile purposes. They have, in fact, passed through a process of
semi-manufacture, such process, as I have explained, being required
to separate the ultimate fibres from the interior woody stem to which
when growing they are attached; and it is obvious that it would not be
(economically) possible to import any of these fibrous plants as grown
or produced, owing to their enormous bulk in that condition.
Now although the stems of the "BAMBOO," after cutting and crushing,
may, as I have shown, be dried (and will when dried give a yield of
60 per cent. of fibre), still their bulk and extreme lightness would
preclude importing them to this country in their _raw_ condition, not
merely from their heavy cost for carriage, but from their liability
to damage from fermentation. For these economical considerations,
therefore, I propose to reduce the "BAMBOO" into "_Fibrous-Stock_"
where grown or produced.
It may be well, before entering into details of the process, briefly
to explain the ordinary system employed for preparing fibres, or
fibrous materials, as also rags, for Paper-making. This consists in
sorting, cutting, cleaning, and, if need be, roughly opening them,
followed by boiling in alkaline leys, after which they are well washed
until cleansed from impurities in what is technically termed the rag
or breaker engine, during which operation they are disintegrated or
reduced into "_Half-stuff_," or _semi-pulp_, this being subsequently
bleached and converted into pulp and paper.
As the object of my process is to produce a fibrous or tow-like
_Stock_, retaining as far as possible the normal or natural condition
of the fibre, and not "_Half-stuff_" or "_Pulp_," my system of
treatment differs materially from the foregoing, more especially in the
boiling and washing processes.
Both of these processes I conduct in a battery, or series of vessels
(16, 20, or more in number), such vessels being connected together
by pipes, or channels, furnished with valves, or cocks, so that
communication between the individual vessels may be maintained,
disconnected, and regulated as desired, in such manner that the
vessels, being methodically charged in succession with the material to
be operated upon, the heated leys (composed of caustic alkali) can be
progressively conducted from vessel to vessel of the series, passing
over and through the material placed therein.
The leys are thus used again and again, (each successive change,
or charge of ley, carrying forward the extractive matters it has
dissolved from the fibre with which it has been in contact) until
exhausted or neutralized, (when they are discharged), fresh leys
being methodically, and successively, supplied, until by degrees, the
extractive matters combined with the fibre or fibrous material have
been rendered sufficiently soluble, when hot water for washing, or
rinsing, is in the same continuous manner run successively from vessel
to vessel, over, and through, the material contained therein, until
the extractive matters rendered soluble by the previous alkaline baths
have been carried forward and discharged, leaving the residuary fibre
sufficiently cleansed.
By this system of boiling in continuity, until all the effective
alkali in the leys is exhausted or neutralized, I realize an economy
of from 30 per cent. to 40 per cent. of soda over the ordinary process
of boiling, and by the subsequent washing, or rinsing, in the same
continuous manner, without removing the material from the vessels, the
normal structure of the fibre is in a great measure retained, waste is
minimized, and thus, while being thoroughly cleansed and freed from
extraneous matter, the strength and staple of the fibre are preserved;
a considerable saving of fuel results from the heated liquors being
used again and again, less steam being required, as also less water,
while at the same time economy of both labour and power is effected
over the ordinary system.
Assuming the boiling and succeeding washing processes to be concluded,
and the material ("BAMBOO") in one of the vessels of the series in its
regular succession, to be found sufficiently treated and cleansed, a
final cooling water is run on and through the fibre, which is then
drained, and the contents of the vessel (disconnected for the time
being from the series) emptied into a waggon running on a railway,
by which it is conducted to a press or otherwise to abstract all the
remaining moisture possible.
The dry, or semi-dry fibre, is then submitted to the action of a
willow, or devil, by means of which it is opened or teazed out, and
converted readily into a tow-like condition, when it is dried by a
current of heated air, induced by a fan-blast, and finally baled up for
storage or transport, in a similar manner to COTTON or JUTE.
In this condition of "_Paper-Stock_," it may be kept an indefinite
length of time without injury, and when received by the
Paper-manufacturer requires merely soaking down and bleaching, to fit
it for making into paper, either by itself, or used as a blend with
other materials, as desired.
The minuter details of my process for treating raw fibres, or fibrous
material, for the manufacture therefrom of _Fibrous_ "_Paper-Stock_,"
are fully described in my several Patents, the only variation so far
as relates to "Bamboo" being the preliminary preparation of the young
stems, the other portions of the process being substantially the same
as in daily operation at the Ford Works, Sunderland, for the treatment
of "Esparto," and other "_raw fibres_."
I have only now further to remark that the "Plant" required to
manufacture "_Paper-Stock_" from "Bamboo" on an economical and
practical working scale, would consist of a battery of boiling pans,
with the other necessary adjuncts and machinery, steam engines
and steam boilers, such "Plant" being on a scale adequate to the
manufacture of 100 tons "Bamboo" weekly, producing therefrom say 60
tons merchantable "_Paper-Stock_."
As the above scale of operations, viz. the Manufacture of 100 tons
("BAMBOO") weekly into "_Paper-Stock_," may appear somewhat large, it
is necessary I should explain that owing to the nature of the Process,
the desired effect being produced by the reiterated and continuous
action of repeated _weak_ Alkaline Baths or Leys, in a Series of
Vessels, such an operation involves the treatment of a large quantity
of "_Raw Material_," at one time, and cannot either conveniently or
economically be conducted upon a much smaller scale.
The cost of the "Plant" and Machinery required for such a Factory
would amount to about ***, packed ready for shipment in England, to
which would have to be added the carriage and cost of erection, with
the necessary buildings, which, however, would be of a very simple and
inexpensive character.
I do not feel myself competent to determine what quantity of Land
would be required for a plantation to supply such a factory, which
would absorb 100 tons dry, say 400 tons green, "Bamboo" stems weekly,
but assuming 40 tons produce to the acre, with only once annual
cropping, 500 acres should be ample. This calculation doubtless would
be influenced by the varying conditions of climate and soil, as also by
the variety of "Bamboo" cultivated.
It may be expected that I should in these "REMARKS" include some
reference to the "_Variety_" of "BAMBOO" which could be most
economically and profitably cultivated for the supply of such a
Factory, on the scale I propose.
In respect to this portion of my subject I experience some difficulty,
inasmuch as the _Varieties_ of "Bamboo" are so numerous, and so widely
distributed.
A Monograph by Colonel (now General) Munro, C.B., published in the
'Transactions of the Linnean Society,' affords the most elaborate and
comprehensive description of the "Bamboo:" in this paper upwards of 170
species are described.
The "_Bambusa Vulgaris_," as its name indeed denotes, appears to be the
most generally distributed, as it is found in both Hemispheres, General
Munro being in considerable doubt as to which it is a native of.
I quote from his Monograph: "I have seen it collected by Wallich, in
Silhet, by Hooker, in Chittagong (both North-east India), from Ceylon
wild, in the Mauritius cultivated abundantly, in the West Indies
naturalized, and cultivated in several parts of South America, this is
the only thoroughly cosmopolitan species."
Bambusa "_Gigantea_," growing to the height of 120 feet and from
25 to 30 inches circumference; B. "_Edulis_," or edible Bamboo; B.
"_Arundinacea_;" B. "_Balcooa_;" B. "_Brandisii_," &c., all varying in
growth to from 60 to 70, to 120 feet high, abound throughout India, and
all our Asiatic Dependencies. In the West Indies also, where not now
indigenous, doubtless any variety selected could readily be introduced
and cultivated.
To conclude, it would appear that with the "_Raw Material_" "Bamboo,"
we have under our control "an embarrassment of riches," and I have only
further to add that I know of no other that can at all approach it in
economy of production, and I believe very few if any in the quality of
the "_Stock_" produced therefrom suitable for Paper-making purposes.