Pocock was a Bristol-born marine-painter with real experience at sea; he exhibited in London at the Royal Academy and Royal Institution between 1782 and 1815 and settled there himself in 1789. He was serving as a mariner on the 'Pegasus' when he witnessed seveal engagements of which five he painted in oils and also recorded in watercolour in an album (now in the National Maritime Museum) along with detailed accounts of the action. This is one of two of these paintings in the Royal Collection (RCIN 402400 and 402001). It illustrates the moment when Rear-Admiral Sir Robert Calder (1745-1818), whose orders were to intercept the French and Spanish fleet returning from the West Indies, engaged three Spanish ships off Cape Finisterre on 22 July 1805. Two Spanish ships were destroyed during the action which lasted for four hours. Calder's ship, the 'Hero', is seen here fourth from the left attacking three Spanish ships, displaying red and yellow flags, amid much gun-smoke. Three English ships appear on the right and more in the background.