King was assigned to survey the parts of the Australian coast not already examined by Royal Navy officer,
Matthew Flinders, (who had already made three earlier exploratory voyages between 1791 and 1810, including the first circumnavigation of
Australia) and made four voyages between December 1817 and April 1822. Amongst the 19-man crew were
Allan Cunningham, a botanist,
John Septimus Roe, later the first
Surveyor-General of Western Australia, and the
Aboriginal man Bungaree. The first three trips were in the 76-tonne
cutter , but the vessel was grounded in 1829. The
Admiralty had instructed King to discover whether there was any river "likely to lead to an interior navigation into this great continent". The
Colonial Office had given instructions to collect information about
topography,
fauna, timber, minerals, climate, and the
Indigenous peoples and the prospects of developing trade with them. King was concerned at this point of the crew's vulnerability to the armed Makassan proas, as the Makassans
harvested trepang (sea cucumbers) and
traded along the northern Australian coast at that time, so he ordered the
cannons to be mounted along the beach. They managed to repair the ship without incident and sailed away in early October 1820, but not before the ship's carpenter had been instructed to inscribe "Mermaid 1820" on an ancient
boab tree, which still stands today.
Fourth voyage King's fourth voyage was undertaken in the 154-tonne
sloop HMS
Bathurst. The ship headed north, through Torres Strait and to the north-west coast of the continent, including the
Dampier Archipelago. Further survey of the west coast was made after a visit to
Mauritius. ==Expeditions to South America==