The accident of a drought in 1813 drove some of the Sydney settlers to look for new pastures in the hinterland. The divide between the short eastward and the long westward drainage systems was surmounted with difficulty; a road to the point where the town of Bathurst afterwards grew up was promptly made, and an arresting geographical problem confronted the investigators when the westward-flowing rivers Macquarie and Lachlan were found. Lieutenant Oxley, R.N., attempting to follow the Lachlan in 1815, was presently brought to a halt by great swamps. He struck south to avoid them, and narrowly missed discovering the Murrumbidgee river, before he turned back to carry to Sydney the conviction that the westward drainage generally was lost in swamps fringing an inland sea. Cunningham found a route from this coast up to the rich Liverpool Plains, towards the north of New South Wales, in 1823; but for the most part exploration was temporarily directed to the south-west, and Hamilton Hume and Hovell in 1824–25 took an inland route from New South Wales to the south coast on the west side of Port Phillip. This inlet was not recognized by them; they returned to report that they had seen the coast-land, and found it good, further to the east at Western Port; settlers who visited that district on their recommendation were disappointed, and the development of the Victoria coast-lands received a set-back in consequence of this error. Cunningham in 1828 opened the route from the coast at Brisbane to the downs of the south Queensland hinterland. In the same year a new phase was entered in the solution of the problem of the far interior, when Charles Sturt, carrying with him Oxley’s conviction of the existence of an inland sea, journeyed inland at a season of drought to find the Macquarie river losing itself on the dry plains, and the Darling flowing salt. He attributed this fact to an admixture of sea-water, and set down the interior of the continent as a desert. In the following year he settled the problem of the drainage of the Murrumbidgee, Lachlan, and Murray rivers by following them to the mouth of the Murray in Lake Alexandrina (south coast); and although he now held that the waters of the Darling were included (as they are) in this system, it was still doubted whether there was a divide between north and south flowing waters about the central latitude of New South Wales, where, in the interior, high ground was known to exist. Sir Thomas Mitchell settled this question by a great journey in 1836, which, among other results, immediately threw open to settlement the fertile country about Port Phillip, hitherto, as we have seen, neglected through the misunderstanding of Hume and Hovell.