2018 schedule

Sun 14:30-15:00
Venue: 
Mercure Conservatory

Timeballs and Telegraphs

Ian Sullivan

ASV, MPAS

In the era of Captain Cook, navigation became a major scientific endeavour, and to measure longitude at sea, the chronometer was invented in England in 1773. Cook first sailed with one on his second voyage, and by 1830's, ships of all nations were similarly endowed, and in need of a time service in all major ports. In 1830 an English RN Captain Wauchope tested the first TIMEBALL at Portsmouth, a hollow copper ball up to a metre in diameter, from a height at an appointed hour, and 1 pm was chosen. A nearby observatory sent a the time signal by telegraph and ships could sight the drop by telescope to correct their chronometers. Nearly 200 timeballs were constructed worldwide, and about sixty still exist as historic relics from the 1920's - as radio supplanted timeballs and telegraphs. Telegraph developed in parallel with timeballs, having a much larger commercial value. Undersea cables, like the Atlantic in 1866 , proliferated and circled the globe. All six colonies of Australia still retain old timeballs and telegraph stations.