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.
Mull. [From Latin mollio, to soften] An extremely thin, soft and transparent kind of muslin, used for dresses, neckwear, trimming, etc. It is woven of fine, soft cotton yarns, free from sizing or starch. Thin, changeable silk is also sometimes termed mull, especially the sorts finished without dressing, and used for millinery purposes.