Signalling with flags
In the early days of the island prison, communication between St Helena and the mainland was by means of flags.
On the island’s highest point, which was practically in the backyard of the Superintendent’s residence, there stood a tall signal tower from which messages were sent by flag to the water police stationed on the prison hulk or at Lytton at the mouth of the river across Moreton Bay.
A red and white flag, for example, could mean that a prisoner had escaped or that the inmates were rioting – and that help was needed urgently on the island.
The flags were clearly visible with the aid of a telescope. The only problem was that, on dull or rainy days, or at night, the flags could not be seen. To overcome this problem, the authorities installed a cannon so that it could be fired to echo its message across the bay that help was needed.
Coded flags were also hoisted above sentry boxes and lookout towers to communicate around the island and beyond.