tussur

Wardle combined his dye experiments with a long-standing interest in India's tussur silk (variously spelt tassar, tussar, tussore or tassah).

Both strands of Wardle's research intertwined when he applied the outcomes of his dye research to his new knowledge of tussur and began to dye the wild silk in permanent colours.

He refused to test tussur with the aniline dyes that were then taking increasing hold on the subcontinent.