Devil’s dust

a term used in the manufacturing districts of Yorkshire to denote shreds of old cloth torn up to re-manufacture; also called shoddy. Mr. Ferrand, in his speech in the House, March 4, 1842, produced a piece of cloth made chiefly from devil's dust , and tore it into shreds to prove its worthlessness.—See Hansard's Parliamentary Debates, third series, vol. lxi. p. 140.