The Sentinal of Semaphore | Australia

Postcard
Semaphore is a suburb located in north-west of Adelaide. The Sentinal of Semaphore’ is a solid stone structure that was built in 1875. At 1pm daily, the black ball drops, signalling ships to rate their chronometers, vital navigation instruments. Similar towers were set up in many cities around the world.

Time Ball is a, today obsolete, time-signalling device. It consists of a large, painted wooden or metal ball that is dropped at a predetermined time, principally to enable navigators aboard ships offshore to verify the setting of their marine chronometers.