Penlee House, Penzance holds a set of original pencil drawings for the Penzance and St Michael's Mount aquatints (produced in 1813) by Daniell for Richard Ayton's book A Voyage Around Great Britain.

In 1799 Daniell entered the RA Schools, following in the footsteps of his uncle Thomas DANIELL (1749-1840) who had become responsible for bringing up his orphaned nephew. This was after William had accompanied his uncle to India, where Thomas worked as an engraver after his own training at the RA Schools (1773) and exhibiting at the RA; hence William was already an experienced landscape painter.  His brother Samuel DANIELL (1775-1811) was a topographical artist.