The Hay Wain is probably Constable's most famous work

The drawings were donated to Exeter Museum, Library and Art Gallery in 1897 after the death of the owner, Mr Edward Fisher of Newton Abbot.

The book, containing more than 100 drawings and sketches, was stored when the library moved in the 1930s.

It was rediscovered in 1976 when local researcher Mike Pidgley chanced upon an index card and rediscovered the works.

The drawings, which depict various stages of Constable's work from copies of old masters and portraits of his wife and his better known landscape studies, were then taken to the Tate Gallery in London for conservation.