Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/489

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W E A W E A 463 being almost invariably domed others (such as the Philippine Weaver-bird, Ploccus philippinus, just named) fabricate singular structures 1 of closely and uniformly interwoven tendrils or fine roots, that often hang from the bough of a tree over water, and, starting with a solidly wrought rope, open out into a globular chamber, and then contract into a tube several inches in length, through which the birds effect their exit and entrance. But the most wonderful nests of all, and indeed the most wonderful built by birds, are those of the so-called Sociable Grosbeak, Philhdserus socius, of Africa. These are composed wholly of grass, and are joined to gether to the number of 100 or 200 indeed 320 are said to have been found in one of these aggregated masses, which usually take the form of a gigantic mushroom, 2 affording a home and nursery to many pairs of the birds which have been at the trouble of build ing it. These nests, however, have been so often described and figured by South-African travellers that there is no need here to dilate longer on their marvels. It may be added that this species of Weaver-bird, known to French writers as the Repiiblicain, is of exceptionally dull plumage. The group of Widow- birds, 3 Viduinse, is remarkable for the extraordinary growth of the tail-feathers in the males at the breed ing-season. In the largest species, Viclua (sometimes called Chera) progne, the cock-bird, which, with the exception of a scarlet and buff bar on the upper wing-coverts, is wholly black, there is simply a great elongation of the rectrices ; but in V. paradisea the form of the tail is quite unique. The middle pair of feathers have the webs greatly widened, and through the twisting of the shafts their inferior surfaces are vertically opposed. These feathers are com paratively short, and end in a hair-like filament. The next pair are produced to the length of about a foot the bird not being so big as a Sparrow and droop gracefully in the form of a sickle. But this is not all : each has attached to its base a hair-like filament of the same length as the feather, and this filament originally adhered to and ran along the margin of the outer web, only becoming detached when the feather is full grown. 4 In another species, V. principalis, the two middle pairs of rectrices are equally elongated, but their webs are convex, and the outer pair contains the inner, so that when the margins of the two pairs are applied a sort of cylinder is formed. 5 The females of all the Widow-birds differ greatly in appearance from the males, and are generally clothed in a plumage of mottled brown. Usually classed with the Weaver-birds is avast group of small seed-eating forms, often called Spermestinse, but for which Estreldinee would seem to be a more fitting name. These comprehend the numerous species so commonly seen in cages, and known as Amadavats, Estrelda amandava, Nutmeg-birds, Munia punctularia, Waxbills, Pyteliamelba and phcenico2)tera, Cutthroats, Amadina fasciata, the Java Sparrow, Padda oryzivora, and many more than we can name. Many of these genera are common to Africa and India, and some also to Australia, but the last has several genera peculiar to itself, such as Donacicola and Poophila^ there known as Grass-finches. The true affinity of these seems to require further investigation. 6 (A. N.) WEAVING is the art of forming cloth by the interlac ing of yarn or other filaments in a loom. In weaving two kinds or sets of yarn are used, the warp and the weft. The warp consists of the threads of yarn which extend generally but not always in parallel lines from end to end the whole length of the web ; the weft yarn crosses and intersects the warp at right angles, and fills up the breadth of the web. The warp is mounted on the loom for weav- 1 These differ from those built by some of the ORIOLES (q.v.) and other birds, whose nests may be compared to pensile pockets, while those of these Weaver-birds can best be likened to a stocking hung up by the "toe," with the "heel" enlarged to receive the eggs, while access and exit are obtained through the leg. " 2 But at a distance they may often be mistaken for a native hut, with its grass-roof. 3 It has been ingeniously sviggested that this name should be more correctly written Whydah bird from the place on the West Coast of Africa so named; but Edwards, who in 1745 figured one of the species, states that he was informed that "the Portuguese call this bird the Widow, from its Colour and long Train" (Nat. Hist. Birds, i. p. 86). 4 This curious structure was long ago described by Brisson (Orni- tholorjie, iii. p. 123), and more recently by Strickland (C ontr. Orni thology, 1850, pp. 88 and 149, pi. 59). 5 Both these species seem to have been first described and figured in 1600 by Aldrovandus (lib. xv. cap. 22, 23) from pictures sent to him by Ferdinando <le Medici, duke of Tuscany. 6 An illustrated Monograph of the Weaver-Birds by Mr Edward Bartlett is now in course of publication. ing, and into it the weft is thrown by means of a shuttle. Weaving is thus distinct from knitting, netting, looping, and plaiting, by all of which methods cloth may be made from yarns. Cloth also is prepared by felting, but in that operation the fibres are simply matted together without either spinning or intertwisting. To appearance the varieties of woven cloth are endless; but these differences are only in part due to the method of weaving. The textile materials employed, the methods used in spinning and preparing yarns, the dye colours resorted to, and the finishing processes may vary indefinitely and so contribute to give variety of character to the resultant pro duct. The complexities of the art of weaving itself are reducible to a few fundamental operations, which do not of necessity demand the most intricate mechanism. The gorgeous mediaeval textiles of which numerous examples remain were made in looms of primitive construction. For producing the Indian muslins of the present day with their marvellous delicacy of texture, and for the elaborate and sumptuous shawls of Kashmir, the weavers have only rude and simple looms. But patient and tedious handiwork in these instances is devoted to produce effects which, with the application of modern machinery, can be automatically secured with as great rapidity as in the case of the plainest fabric. The series of inventions which have led up to the marvel lously ingenious looms of the present day began with the invention of the fly shuttle, so called because of the rapidity of its motion, by John Kay of Bury in 1733. Previous to Kay s time the shuttle was thrown by the weaver s hand across and through the warp threads from side to side of the web. His invention brought the plain hand-loom practically into the form in which it continues at present ; and, as it forms the basis of all modern ma chinery, a description of its parts and working, and of the operations connected with plain weaving, may here be given. In accordance with the definition already laid down, plain cloth, such as an ordinary piece of calico or linen, will, on examination, be found to consist of two sets of threads, the one intersecting the other at right angles, with each single thread passing alternately over one and under the next. Such a web is produced by passing the weft thread over and under each alternate warp thread in the breadth of the loom, the warp threads under one shot of weft being above the next. To do this, and to beat or close up each successive weft thread so as to make an even and suffi ciently close cloth, necessitates a series of operations of which the following is an outline. Warping. The number of longitudinal threads which go to form the web will vary, of course, according to its breadth and to the closeness with which they lie together ; for fine webs several thousand warp threads, of sufficient length to form a web of many yards, may have to be laid parallel to each other. This is done in the warping frame, which consists of a large reel, set vertically, on which separate threads drawn from a range of bobbins are wound together in a spiral manner to the required length of the web. The yarns coming from the bobbins are brought together in a heck, which is made to slide up and down a guide post as the reel or warp ing frame revolves, and thus it delivers to the reel a band of thread which winds up and down the reel spirally by the rise and fall of the heck. Supposing 100 "ends" or warp threads are being reeled from bobbins, and 1000 ends of warp are required in the web, then the full lengths wound on the reel must be repeated upward and downward ten times. At each end of the warp the threads are, by a mechanical device in the heck, made to intersect alternately, forming leashes which are, when taken from the reel, separately tied up, and thus aid in maintaining the parallelism of the ends when they are bundled up. Such a bundle of warp when required for weaving is taken in hand by the beamer, whose duty is to spread the threads evenly and wind them on the warp beam, spreading the ends in the order in which they are to appear in the woven fabric, and giving them about the breadth of the web. Cotton warps are wound direct from the bobbins on the beam, there being a mechanical arrangement in the warping machine

which stops its motion when any thread breaks, or when a bobbin