Duncan began his career working for an aquatint engraver; for over fifty years he exhibited his watercolours, mainly marine subjects, at the Old, and New, Watercolour Societies. Marine painters could either specialise in depicting the accurate details of particular types of ships and boats, giving details of their construction, sails and rigging, or, like Duncan, give a less specific view of the coast, usually with some element of human activity to give more vitality to the scene. Here, the job is carting seaweed a marine algae that was of great economic significance. The labour and labourers depicted here may be construed in the same sense as those in De Wint's Cornfield or Linnell's Harvest Moon (cat.nos. 134 and 52).