Now, I infer from these facts, that the population, animal as well as vegetable, proceeded from one country to the other; and that many forms of vegetation in the two colonies possess no greater difference, than the difference of soil and latitude may account for; and that it may therefore be possible for men to find a route from one country to the other, by carefully noting and following the lay of the water-courses, the direction of the oases, and the nature of the geology of the country; for that no impenetrable desert exists between the countries, is evident from the passage of vegetables and animals from the one to the other. What will be the benefit, some one may ask, when such a route is discovered? Why, independent of the knowledge gained to geography, there will be the great practical good of opening the boundless pastures of Western Australia to the flocks of the already overstocked lands of the other colonies. To Western Australia the gain would be great; and to South Australia it would be equally advantageous, as it would maintain the value of stock there, which will rapidly fall when no more land can be found fit for occupation. Even with all the rapid increase of population which the great mineral abundance of that colony will continue to create, sheep will multiply faster than the population, until they become of the same low value as in New South Wales, where, if there be no run sold with them, they are not worth more than the value of the wool on their backs. It is therefore most desirable that attempts should be made to find a stock route from the western to the eastern coasts. Intra-tropical Australia is more abundantly supplied with rivers, and of a larger magnitude, than any out of the tropics, the Murray alone excepted; and doubtless a journey across the island within the tropic would present fewer difficulties than one direct from Perth to Sydney, or Adelaide; but, excepting for the advancement of geographical knowledge, there is no object to be gained by such a journey. The best way is along the valley of the lakes, guided as the party proceeds, by the nature of the country. I earnestly hope that an expedition will be sent to make some effort to penetrate the great extent of an unknown country, lying east of Western Australia, as it is an object well worth the attention of the Government, or of the Geographical Society.