FIBRE (Lat. fibre, filament). A term of very common use as applied to objects of a stringy or thread-like character, whether of the animal, vegetable, or mineral kingdom. Minerals are often described as of a fibrous structure or ap pearance. in which there is, however, no possibil ity of detaching the apparent fibres from the general mass, or in which they are inflexible, and brittle if detached; but a more perfect ex ample of mineral fibre is found in amiantus, a variety of asbestos. For the scientific use of the term fibre with regard to the animal kingdom, see the article MUSCLE AND MUSCULAR TISSUE; for its scientific use with regard to the vegetable kingdom, see VEGETABLE TISSUE; NVO0D. In its more popular but perfectly accurate use, it includes the hair or wool of quadru peds, the silken threads of the cocoons of silk worms and other insects, the fibres of the leaves and of the inner bark of plants, and the elon gated cells or hairs connected with the seeds of plants. the ordinary materials of cordage, and of textile fabrics.
Of mineral substances, amiantus alone has been used for textile fabrics, and that only to a very limited extent. Animal and vegetable fibres have, from the earliest ages, supplied man with cordage. and with cloth. How the invention took place can only be matter of conjecture. It is noted as an interesting fact that the most valu able commercial fibres of to-day were the promi nent fibres of ancient times. Cotton, flax, hemp, as well as the common animal fibres, as hair, wool, and silk, were known and used in past ages.
The animal fibres used for textile purposes are chiefly of the two classes already mentioned—(1) the wool or hair of quadrupeds, and (2) the silk of the cocoons of insects. To these may he added (3) the byssus of mollusks, hut this class con tains only tile byssus of the pinny (q.v.) of the Mediterranean. an article of ancient and high reputation. but more of curiosity than of use. The skins and intestines of animals, although sometimes twisted or plaited for various uses, can scarcely lie reckoned among the fibrous ma terials afforded by the animal kingdom. For in
formation regarding the fibres obtained from the cocoons of insects, see Sum: and SILEwoRm. It is to the first class that the greater number of dif ferent kinds of animal libres used fur textile pur poses belong; and the wool of the sheep far ex ceeds all the rest in importance. But the wool or hair of other quadrupeds is also to sonic extent used, as that of the goat. the alpaca, the comet, the musk-ox, and the yak, all of which are, like the sheep, ruminants. The hair of comparatively few animals is sullieiently long for textile purposes, or can be procured in sufficient abundance to make it of economic importance. The warmth of clothing depends much on the fineness of the hair, and on other characters in which wool par ticularly excels. See ShEEP; WOOL; GOAT; ANGORA: ALPACA; CAMEL; MUSK-OX; YAK.
The useful vegetable fibres are far more nu merous and various than are the animal. They are obtained from plants of natural orders very different from each other. They are obtained also from different parts of plants. Wood-cells are found in the bark, and are longer, finer, and tougher than those found in the wood. They form the principal part of the fibrous bark or bast layer of cells. These give toughness and flexibil ity to the structure, and the extracted bundles of cells form the filathentous product, known as flax, hemp, and jute, derived from dicotyledo nous plants. In monocotyledons the fibrous cells are built up with others into a composite struc ture known as fibro-vascular bundles. Such fibre occurs in the palms, and in the fleshy-leaved agaves, the bundles being found not as in bark, but throughout the stem or leaf forming the sup porting structure. These filaments, when sepa rated from the soft cell-mass by which they are surrounded, may be known as structural fibre, of which the fibre of sisal hemp is an example. The simple cells produced on the surfaces of the seeds of endogens, such as cotton and cocoanut, constitute a fibrous material, to which the name surface fibre has been given. For illustrations see plate of FIBRE PLANTS under article HEMP.