John Worsley joined the Royal Navy in 1939. His depictions of life on board ship were soon acquired by the War Artists Advisory Committee (WAAC), and he was quickly made an official war artist. In 1943, he was captured in the Mediterranean and spent the rest of the war in a naval officer's prison camp, Marlag ‘O’ at Westertimke, near Bremen in north Germany.
War at sea was said to be 90% boredom and 10% terror, with long hours of waiting interrupted by violent action. These two sketches give a sense of the strenuous roster of four hours on watch and four off, to which seamen were often subjected. Exhausted, they would drop asleep fully clothed, ready to spring back on deck at any alert. The caption ‘Jerry or no Jerrys!’ (i.e. Germans) evokes how, despite the need for constant watchfulness, sleep became irresistible.

[Mounted with PAI0617, which is a detail of the same man's head. The man appears (though more clearly from the other drawing) to be stretched out on a couch rather than in a standard lower bunk.]