John Craske was a Norfolk fisherman born in 1881, who fell ill in his mid-thirties, after which his life consisted of long periods lying helplessly in what were described as ‘stuperous states’, and others in which – always supported by his wife, Laura – he painted obsessively on whatever surface was available: scraps of paper, bits of wood, cardboard boxes, doors, windowsills, household objects. His subjects were boats at sea or stretches of the coast. When, even in his active phases, he became too weak to stand up, he took to needle and thread and made embroideries of the same subjects as he lay in bed. These culminated in a wonderful work, almost three yards long, depicting the evacuation of British troops from Dunkirk by the Royal Navy and over eight hundred civilian vessels: an event so heart-stopping that it made disaster seem like triumph, and which had moved him profoundly. There was still a small piece of sky unfinished when he died in August 1943.

Craske was ‘discovered’ by the novelist Sylvia Townsend Warner, her flighty lover Valentine Ackland and an American lover of Valentine called Elizabeth Wade White, who between them worked up a modest degree of recognition for his work, just enough to keep him going but not enough to last. When Julia