In 1760 Robert Adam was employed to design a screen consisting of columns in front of a wall, with pavilions at the ends and a gate in the middle.
The gate has a pair of winged hippocampi or seahorses, very appropriate for a navy that was propelled round the world by the wind. The pavilion pediments are carved with ship's prows - on the right a Roman galley with another hippocampus, a ram in the shape of three of the short stabbing swords used by Roman soldiers, and a brazen eagle's head.
On the left is a British warship with a lion figurehead. The message is clear - the Navy is the power of the new Imperium.
The sculptor was Michael Henry Spang, a Dane who had found fame with a flayed figure in bronze that he made for the noted surgeon William Hunter, under whom he had studied anatomy.
Spang was one of Adams' favourite sculptors but unfortunately died shortly after the Admiralty screen was completed.