Who they were
Matthew Flinders joined the navy young and surveyed the coasts near the early colony. Between 1801 and 1803 he became the first to circumnavigate the Australian continent, in the Investigator.
What they did
He charted the coastline precisely and confirmed that the eastern and western lands, once thought separate, were one continent. He urged that it be called Australia.
Legacy
On his way home he was detained by the French at Mauritius for more than six years. He died in 1814, just as his charts and account were published, but the name Australia eventually took hold.