The larger problems of Australian geography were thus early settled, though there was (as even now there is in some parts) a multitude of details to be filled in. But the leading questions awaiting solution by explorers now become economic rather than purely geographical. Thus we find Dr. Leichhardt’s first expedition (1844), from Moreton Bay in southern Queensland by the Burdekin, Mitchell, and Roper rivers to Port Essington, inspired by the conception of an overland route between Sydney and a northern seaport. He was lost (and the mystery of his fate was never solved) in 1848 in attempting a crossing of the continent from east to west, and Kennedy’s expedition in the same year, in attempting to cross northern Australia, also met with disaster, where A. C. Gregory succeeded in 1855–56. The penetration of the interior from the south and the crossing to the north had attracted travellers before this; Eyre in 1840 had discovered the series of salt lakes and swamps which he lumped together under the name of Lake Torrens, while Sturt in 1845 added little to Eyre’s discoveries, and, after failing to penetrate the Stony Desert to the north, put a temporary period to explorations in that quarter. Babbage in 1856 and Parry in the following year obtained more accurate knowledge of the Lake Torrens region, and Goyder in 1857 reported a great freshwater lake which was found later to have been conceived out of some shallow pools and visions of the mirage. J. M. Stuart’s six expeditions from south to north in 1858–61 added much to exact knowledge; that of Robert Burke and William Wills in 1860–61, ill-managed as it was and ending in the death of the leaders, obtained a fame in excess of its scientific value; but other expeditions sent in search of it achieved better results, and incidentally made clear the danger of assessing the worth of some of the inland districts on the report of one traveller who might have come upon them at an unfavourable season. Thus J. McKinlay in 1861 brought word of fertile lands which Sturt had condemned as desert. The many journeys through the interior of Western Australia--such as those of J. S. Roe (1836), the brothers Gregory, H. M. Lefroy (1863), Sir J. Forrest (various expeditions in and after 1869), Warburton (1873), and Ernest Giles (first crossing from Adelaide to Perth by an inland route, 1875)--though often of extreme importance from an economic point of view, whether concerned with the discovery of pastoral lands or of gold or other mineral fields, can only be referred to here as having gradually opened up the detailed knowledge of this part of the continent, and as having redeemed it in part from a reputation for complete inhospitality, until we have now a trans-continental railway planned to connect the systems of south and of western Australia. The exploration of the Kimberley and north-western areas of the state was delayed until the latter half of the last century. CHAPTER XIII.