In 1801, Matthew Flinders was given command of the "Investigator" to chart the remaining unexplored coastline of Australia. He had previously engaged in Australian coastal exploration and was a navigator of outstanding ability.

Arriving at the south-west corner of Australia in December, he surveyed the south coast from Cape Leeuwin to Port Phillip Bay and explored and named Spencer's Gulf. He also proved that Australia was not divided into two large islands as some people had imagined.

Setting out again from Port Jackson in July, 1802, Flinders followed the coast northward and arrived in Torres Strait in October. Having charted the Gulf of Carpentaria, he continued his voyage and, stopping at Timor for repairs, sailed round the continent, to arrive in Sydney on 9th June, 1803.