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 11/2 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 5s. per ton, for the green stems, delivered to the central factory, and 40 tons to be produced per acre, we have the sum of 10l. 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.