Mitchell favoured the search for a practicable road to the Gulf of Carpentaria, and hoped also that he would at last find his long-sought northern-flowing river. In a letter which he then received from a well-known grazier, Walter Bagot, there is mention of an aboriginal description of a large river running northward to the west of the Darling. But as natives in their descriptions frequently confuse flowing to and flowing from, they probably had Cooper's Creek in mind. During the earlier part of the year, Commissioner Mitchell, the son of Sir Thomas, who was afterwards drowned during a passage to Newcastle, had made a flying survey towards the Darling, and the discovery of the Narran, Balonne, and Culgoa rivers has been attributed to him. On the 15th of December, 1845, Mitchell started from Buree with a very large company, including E.B. Kennedy as second in command, and W. Stephenson as surgeon and collector. He struck the Darling much higher than Fort Bourke, and it was not until he was across the river that he passed the outermost cattle-stations, which had sprung rapidly into existence since his last visit to the neighbourhood. The Narran was then followed up until the Balonne was reached. This river, in his superlative style, Mitchell pronounced to be the finest in Australia, with the exception of the Murray. He then struck and followed the Culgoa upwards until it divided into two branches; he skirted the main one, which retained the name of the Balonne. On the 12th of April he came to the natural bridge of rocks which he called St. George's bridge, and which is the site of the present town of St. George. Here a temporary camp was formed; Kennedy was left in charge to bring the main body on more slowly; Mitchell with a few men went ahead. He followed up the Balonne to the Maranoa, but as the little he saw of that tributary did not tempt him to further investigation of it, he kept on his course up the main stream until he reached the junction of a stream which he named the Cogoon. This riverlet led him on into a magnificent pastoral district, in the midst of which stood a solitary hill that he named Mount Abundance. It is in his description of this region in his journal that we first find an allusion to the bottle tree. The party wandered on over a low watershed and came down out on to a river which, from its direction and position, he surmised to be the Maranoa, the stream he had not followed. At this new point it was full of deep reaches of water, and drained a tract of most pleasing land. On its banks he determined to await Kennedy's arrival.