“In 1918,” says Carruthers, “a new RAF uniform in blue-grey came out ... as well as some of the fabrics. “We, as a nation, really do not know enough about what has come out of the Scottish ...

Ancient South Americans made blue fabrics to dye for. A piece of approximately 6,000-year-old woven cotton material from Peru gets its blue hue from indigo dye, making it the oldest known example ...