Dyeing. [f. FLY sb.1 + DUNG v.] trans. In the process of dyeing with madder: To subject for the first time to the process of ‘dunging’: see DUNG v. Also Comb. as fly-dung bath, cistern. Hence Fly-dunging vbl. sb.
The name is said to be due to the fact that the object of the first dunging is to get rid of the ‘flies’ or irregularities in the dyeing.
1860. Higgin, in Ure, Dict. Arts (ed. 5), I. 531. The first [dunging process] is called fly-dunging. Ibid. The fly-dung cistern.
1876. Paton, in Encycl. Brit., IV. 687/2. Immediately after the fly-dunging the goods are washed and submitted to a second dunging.
1883. Bleaching, Dyeing & Calico-Print, iii. 73. The fly-dung bath.
