This section is from the "A Complete Dictionary of Dry Goods" book, by George S. Cole. Also available from Amazon: A complete dictionary of dry goods and history of silk, cotton, linen, wool and other fibrous substances,: Including a full explanation of the modern processes ... together with various useful tables.
Denim. [A trade name; origin unknown]. A coarse cotton twilled material used for men's overalls and working shirts; the quality is denoted by the weight in ounces per square yard, ranging from 6-oz (light) to 12-oz (heaviest). This fabric has since 1889 been utilized to a small extent for curtains and portieres, and the denim which is so familiar with the trade in the peculiar grayish blue, is now made for drapery purposes in browns, golds, olives, reds and all of the various shades likely to please the best elements of the trade. The goods are 50 inches wide, and embroidered in the same character of cord work that is seen in tambour lace curtains. [See Tambour].