A 1917 article from Posselt's Textile Journal explaining how light reflects from flat, rough and curved surfaces and how this governs the lustre, light and shade, and color of woven fabrics. Ray diagrams (Figs. 1, 2, 4, 5) illustrate the principles, and photographs of a fancy repp fabric with floating warp figures (Figs. 3 and 6) show the effect of changing the viewing angle. It also discusses the influence of yarn twist, fibre shape, finishing and the nature of the light source on a fabric's appearance.