Intersections per inch =

120

4

70)

480

(66⁄7 per cent. contraction.

420

60

In a plain cloth the warp intersects every pick, and so the intersections per inch are the same as the ends per inch. In a “two and two” twill the warp intersects twice in four picks, and the intersections per inch will be one-half the picks.

In more medium cloths the multiplier 3 is used; as, for example:—