Matthew Flinders noted red cliffs on the west side of Cape York Peninsula, later identified as the world's largest deposit of bauxite.
Matthew Flinders names Brampton Island and its twin, Carlisle Island as M Island.
Details from Scott, E. The Life of Captain Matthew Flinders R.N. Sydney, Angus & Robertson, 1914
July
21 Flinders sets sail from Sydney Harvbour on the Investigator, commencing the voyage that produced the first circumnavigation of Australia.
August
7 Flinders discovers Port Curtis, named after Sir Roger Curtis, admiral at the Cape of Good Hope who had been helpful to the Investigator on her voyage out from England.
In Keppel Bay ... the master's mate and a seaman became bogged in a mangrove swamp, and had to pass the night persecuted by clouds of mosquitoes. In the morning their plight was relieved by a party of aboriginals, who took them to a fire whereat they dried themselves, and fed them on broiled wild duck. Natives were encountered at every landing-place, and were invariably friendly.
21 Flinders enters Port Bowen , which had escaped Cook's notice and was nearly missed by Flinders as well. He named it after Captain James Bowen of the Royal Navy.
September
28 Near the Percy Islands Flinders sets out to find a passage through the Barrier Reef to open water so he could make the utmost speed for Torres Strait and the Gulf of Carpentaria. After trying several openings he found Flinders' Passage (latitude 18 degrees 45 minutes south, longitude 148 degrees 10 minutes east) north-east of Cape Bowling Green. Three anxious days were spent in tacking through the untried passage.
October
20 In the afternoon a heavy swell under the ship from the eastward meant Flinders had reached the open sea and the Investigator was headed for Torres Strait.
28 The Investigator enters Torres Strait using a passage through the reef found by Captain Edwards of the Pandora in 1791, which Flinders marked on his chart as Pandora's Entrance (generally marked Flinders' Entrance on modern maps). He preferred this opening to the one further north, found by Bligh in 1792.
29 Investigator was brought to anchor under the lee of the Murray Island. Immediately afterwards three long Papuan canoes, carrying about fifty natives, came in sight. Remembering the attacks he had witnessed in the Providence, Flinders kept his marines under arms and his guns ready, and warned his officers to watch every movement of the visitors. But the Papuans were merely bent on barter on this occasion, hatchets especially being in demand. Seven canoes appeared on the following morning. "Wishing to secure the friendship and confidence of these islanders to such vessels as might hereafter pass through Torres Strait, and not being able to distinguish any chief amongst them, I selected the oldest man, and presented him with a handsaw, a hammer and nails, and some other trifles; of all which we attempted to show him the use, but I believe without success; for the poor old man became frightened on finding himself to be so particularly noticed."