Cloths Woven by Tappets.
Among the cloths woven on tappets there are twills, cloths in which a figure is woven diagonally across the cloth by raising the healds consecutively. They are in large variety, being woven on three shafts upwards and not confined to the lifting of a single heald at each pick; as in some cloths two or three out of a larger number may be raised, but the same number is up at every pick, although moving one end or more at each pick. A serge is a modification of a simple twill woven in this manner. [Fig. 44] represents a 4-shaft twill rising one in four, while [Fig. 45] shows a 4-end twill rising two in four, called a denim, swansdown, or cashmere twill. The satin weave is a broken twill—that is, instead of lifting consecutively at each pick, an end, or in some cases two ends, are passed over, as shown in [Fig. 39] (sateen). The ends are lifted in this order: 1, 3, 5, 2, 4. A 5-stave, showing a weft satin, is the standard for sateen. The satin or broken twill applies to any number of twill staves—e.g., a 12-stave satin, passing 4 ends over, lifts 1, 6, 11, 4, 9, 2, 7, 12, 5, 10, 3, 8.
A perfect satin never shows contiguous ends lifting together, as such would give a “spotty” appearance. As almost all the weft shows at one side of the cloth, the parallelism of the threads gives to this weave its well-known lustre, but unless fine yarns and reed with heavy pick are used a very frail structure is the resultant.
Stripes are of various kinds. The herring-bone or reversed twill forms an undulating pattern by using a point draft. Simple figures, on not more than six or eight staves, woven cramped between stripes of plain, are called doriah stripes.