Oxley returned by boat, his companions overland.
3.4.THE BRISBANE RIVER.
It was in October, 1823, that Oxley left Sydney on the expedition that resulted in the finding of the Brisbane River, and the foundation of the settlement at Moreton Bay.

He was despatched on a mission to examine certain openings on the east coast, and report on the suitability of them as sites for penal establishments.

Moreton Bay, Port Curtis, and Port Bowen were selected; and Oxley left in the colonial cutter Mermaid, with Uniacke and Stirling as assistants.
As the cutter went up the coast, she called at Port Macquarie, and Oxley had the pleasure of noting the rapid growth of the settlement that had been built upon his recommendation.

Further along the coast, Oxley discovered and named the Tweed River.

The Mermaid reached Port Curtis on the 6th of November, and cast anchor for some time, during which Oxley made a careful examination of the locality, his opinion of it as a site for a settlement being decidedly unfavourable.