1855-56 Augustus Gregory was asked to lead an expedition across the north of the continent comprising 19 men, with 50 horses and 200 sheep to the interior with his brother, H. C. Gregory, as second in command and Baron von Mueller as botanist. The party left Moreton Bay by sea on 12 August 1855, and proceeded to Pearce Point (Joseph Bonaparte Gulf), and at the estuary of the Victoria River. The party split up, with one group going up the river in a schooner, while Gregory led the other over the range. Gregory led forays up the Victoria River and traced Sturt's Creek for 483 km until it disappeared in the Tanami Desert. The party explored the Elsey, Roper and Macarthur Rivers, then travelled back to Brisbane by way of the Flinders, Burdekin, Fitzroy and Burnett Rivers, arriving back in Brisbane on 16 December 1856 Journals of Australian Exploration.