The Blue Ship by Alfred Wallis, c.1934. From the Tate:
Alfred Wallis spent most of his working life as a fisherman but by the time he was discovered in St Ives by Ben Nicholson and Christopher Wood in 1928 he had become a rag and bone merchant. He began painting at the age of seventy to keep himself company. Wallis painted memories of deep sea fishing boats which were no longer in use. He also painted landscapes based on the surrounding area. Nicholson and Wood were impressed by the directness of Wallis’s work, his use of irregular shaped pieces of cardboard as a support and ground, and the object-like quality of the paintings. The discovery of Wallis encouraged them to pursue further their adoption of a ‘naive’ vision.