The plant is perpetuated by shoots from its base, and multiplies rapidly. The leaves, measuring about 3 ft. long, by in. wide, may be removed bodily, after harvesting the fruit. When the plant is grown for its fibre, however, as in the Philippines, it is customary to pluck the fruit before it matures, as this causes a considerable extra development of the leaves. The method of extracting and bleaching the fibres, as conducted by the Chinese in Singapore, is as follows : The first step is the removal of the Really sides of the leaf. A man, sitting astride a narrow stool, extends on it in front of him a single leaf, one end of which is held beneath him ; he then, with a kind of two-handled bamboo plane, removes the succulent matter. Another man receives the leaves as they are planed, and with his thumb-nail loosens the fibres about the middle of the leaf, gathers them in his hand, and by cue effort, de taches them from the outer skin. The fibres are next steeped in water, washed, and laid out to dry and bleach on rude frames of split bamboo. The processes of steeping, mashing, and exposing to the sun, are re peated until the fibres are considered to be properly bleached. In the Philip pines, the blunt edge of a potsherd is used, and the fibre is carefully combed, and sorted into four elaases.
The above processes are, of necessity, exceedingly tedious, and unsuited to the needs of a commercial un dertaking. To supersede them, several machines have been invented. Some of these have been already noticed on pp. 913-916, when speaking of similar fibres. Fig. 632 shows the Sanford and Mallory machine, which is said to be capable of cleaning 6000-8000 pine-apple leaves daily. It consists of an iron framework, about 4 ft. square, carrying a cylinder 30 in. in diameter, covered with an elastic material, and armed with transverse teeth and scrapers, of varying construction, according to the kind of plant worked upon. About half the circumference of the cylinder is in contact with, and drives, an endless elastic belt, similarly armed with teeth and scrapers, and capable of adjustment to bear with more or less pressure against the cylinder. The width of feed is 16 in. The feed rollers, one elastic, and the other of corrugated metal, move more slowly than the cylinder and belt, and thus hold the leaves firmly, while introducing them to the combing and scraping processes within ; they have also a reverse motion, so that the leaf may be withdrawn when half dressed, and its ends reversed. During the operation; cold water from a 1-in. pipe is kept flowing over the cylinder and belt, and among the fibre, so as to dissolve and wash away the viscid juices of the plant, and prevent that action of the atmosphere which tends to discolour the fibres. The machine weighs about 9 cwt., requires 1 H.-P., and can be worked by one man, with two boys to feed in the leaves and take out the fibre. The speed required is 80-90 rev. a minute. When the leaves are so thick as not easily
to enter the rollers, they crushed between rollers, which will also cut them into strips lengthwise. The reference letters indicate :—A, change-pinion for regulating speed ; B, tightening screw for belt ; C, lever for reverse motion; D, feed-rollers ; E, stud-plate for adjusting inter mediate motion ; F, perfo rated trough for distributing water over the plant being crushed. Fig. 633 shows a modified form.
Fig. 634 shows a section of the leaf of the plant, magnified 100 times : a, epidermis ; b, fibre-vascular bundles, which present the singular peculiarity of being coloured blue by test H; c, centre of the bundle, con taining ducts, and tissue in course of formation ; d, par enchyma. The filaments are very fine, transparent, strong, and supple ; they separate easily by washing and tritu ration. The isolated fibres are fine, uniform in diameter throughout, hut of varying size ; they are solid and glossy„ supple and curly. They taper very gradually towards the ends, which latter are never sharp, but generally rounded, or blunted. The lengths vary from 0.118 in., to 0.354 in. : mean, 0.196 in.; the diameters are max., in. ; min., 0'0000137 in. ; mean, 0'0000216 in Scarcely any fibre possesses such a combination of good qualities. Its breaking strain has been esti mated at 260-350 lb., a 12-thread rope breaking at 924 lb. ; it is remarkably durable, and unaffected by immersion in water ; and is white, soft, silky, flexible, and long in the staple. In the Philippines, and in Singapore and Malacca, the untwisted fibres are woven into textile fabrics—the Nipis de Tina of the former—which are considered the finest in the world. The fibre, intended for a similar purpose, is a large article of commerce between Singapore and China. Fishing-lines and ropes are also made of the fibre ; and in the Rungpore district, the leaves are retted for 4-5 days, and the fibres are converted into twine, used by local shoemakers. The facts that the plant is in great abundance and found growing wild, needing next to no care for cultiva tion, while yielding a most valuable fibre, which is capable of being manufactured, on flax machinery, into textile fabrics, and requiring only to be tanned in order to afford an excellent rope-making material, point it out as deserving unusual attention on the part of tropical agriculturists. A sample of the fibre, exposed for 2 hours to steam at 2 atmos., boiled in water for 3 hours, and again steamed for 4 hours, lost 6'49 per cent. by weight, as compared with flax, 3'50 ; Manilla hemp, 6'07 ; coir, 8'18 ; Russian hemp, Slips of unsized paper, weighing 39 gr., made from the fibre, bore an average weight of 741 lb., as against Bank of England note pulp, 47 lb. It works "wet" in pulping; but makes a good and very strong paper, which bears ink well. (See FruitPine-apples.) Andromachia igniaria.—Exogen. Native of Quito. Affords a good fibre.