Sir John William Kaye.
Indigo factory, Bengal. In this view, the plants (Indigofera tinctoria) were soaked in large tanks or vats of water to releasing their blue colour, and would then float to the top to be retrieved and dried, Chromolithograph.
London: Day and Son, 1867.
From: William Simpson, India, ancient and modern: a series of illustrations of the country and people of India and adjacent territories.
London, British Library.
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