A 1908 article from The Craftsman, the fourth in Professor Charles E. Pellew's series on dyeing for arts and crafts workers, covering indigo and the other vat colors. It traces indigo's history and synthesis, compares fermentation, copperas-lime, zinc dust and sodium hydrosulphite vats, and gives step-by-step directions for dyeing cotton with indigo and the Indanthrene, Algol and Thion vat dyes. It closes with a review of cotton dyeing, including recipes used at Greenwich House for home-dyed rag rugs (manganese brown, copperas yellow and orange, Thiogene Cyanine blue, indigo blue).