It is interesting to make an "apparte" on the subject of indigo dye and to quote Rebecca Stone Miller from "To Weave for the Sun", "'To dye fiber indigo blue, the dried material (after the separation of the unsoluble pigment from the white glycoside) must be returned to its white state by being deoxidised and dissolved; most cultures use a bath of ammonia produced by fermented human urine. Fibers immersed in the bath will not display the blue dour until oxygen is added . As if by magic, the blue colour develops before the dyers eves as the fiber is drawn out into the air and dried. Obviously, it is of the utmost difficulty to end up with a strong, evenly coloured blue thread when the process is conducted completely blind ' The textile artists developed powers of vis ualisation.