Sailor’s eye chart (square)

The flags on the eye chart spell out ‘I see no ships, only these flags’

Admiral Nelson had lost the sight in his right eye in action in Corsica in 1794 and used this to his advantage during the 1801 Battle of Copenhagen when he put a telescope to his blind eye and supposedly uttered the immortal line, ‘I see no ships’, and thus ignored the flag signals from his commanding admiral calling on him to end the action and retreat. He and his men went on to win the engagement.