William Bragg, Charles Todd send Australia's earliest radio signals between Adelaide city, Henley Beach in 1899

The equipment used by South Australia’s postmaster general and telegraph superintendent Charles Todd to send Australia's first radio signals in Morse code (see bottom of inset) from the Adelaide Observatory (inset left) on West Terrace, Adelaide city, to his son in law, Adelaide University physics professor and future Nobel prize winner William Bragg, at Adelaide's Henley Beach (inset right) in 1899.
Images (Henley Beach by Ernest Gall; observatory by South Australia government photographer) courtesy State Library of South Australia

William Bragg and Charles Todd were involved in sending one of Australia’s first radio signals in Adelaide in June 1899. These were Morse code messages, including one over eight kilometres from the Charles Todd’s Adelaide Observatory wireless hut on West Terrace, Adelaide, to the Bragg family’s hut at Adelaide's Henley Beach.

Bragg, Adelaide University mathematics and physics professor and future Nobel Prize winner with his son Lawrence, had been diverted into the possibilities of radio or “wireless telegraphy” by his father in law Charles Todd, South Australia’s postmaster general and superintendent of telegraph. Todd was irritated by the rupture of an underwater communications cable linking the Althorpe Island lighthouse, off South Australia's Yorke Peninsula, with the mainland at Cape Spencer. Todd asked Bragg to look into the possibilities of wireless telegraphy.

While overseas on study leave in England in 1898, Bragg met with Guglielmo Marconi and discussed his experiments with Hertzian radio waves. Unable to obtain backing in Italy, Marconi had moved to London where he was supported by William Preece, the British Post Office’s engineer in chief.

Returning to Adelaide in 1899 and, working with Todd, Bragg started his own research on wireless telegraphy. Adelaide University instrument maker Arthur Rogers made the Marconi apparatus that enabled the Morse messages to be sent by Todd from the Adelaide Observatory near West Terrace, Adelaide city. The messages  were returned by Bragg at Henley Beach.

Todd planned to try radio transmissions over water but he didn’t have time for the project. Nor could he get from England the apparatus he needed, and the cost of a lighthouse link was too high because skilled operators would be needed at both ends.

In 1899, Bragg gave lectures and demonstrations on “wireless telegraphy” to overflow audiences. His work in this area was abandoned early in 1900 but Bragg had further widened his experience of experimental physics and it brought him progressively closer to original research and the shared Nobel Prize for physics.