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Rh A femur bone of the dinornis, the gigantic extinct bird of New Zealand, has been discovered in the drift on Peak Downs in eastern Australia, at the depth of 188 feet; and this would lead to the belief that land once existed where now the Pacific Ocean separates by a thousand miles two countries of Australasia, whose present animal and vegetable races have so little in common.

Minerals. The useful and precious metals exist in considerable quantities in each of the five provinces of Australia. New South Wales has abundance of gold, copper, iron, and coal, as well as silver, lead, and tin. The mineral riches of Victoria, though almost confined to gold, have been the main cause of her rapid progress. South Australia possesses the most valuable copper mines. Queensland ranks next to the last-named province for copper, and excels her neighbours in the production of tin, while gold, iron, and coal are also found in considerable quantities. In Western Australia mines of lead, silver, and copper have been opened ; and there is much ironstone.

The discovery of gold in New South Wales and Victoria took place in 1851, and during the next twenty years Victoria exported 40,750,000 oz. of the precious metal, while New South Wales, from 1851 to 1871, exported nearly 10,000,000 ounces. The Queensland gold mines, since 1860, have displayed increasing promise; up to the end of 1872 they had yielded rather less than 1,000,000 ounces ; but much was expected, at a more recent date, from the Palmer River and other districts of the north. The yearly value of the aggregate gold exports of Australia, on the average of fifteen years, has been 10,000,000. Vic toria alone has produced gold to the value of 170,000,000. The alluvial gold-fields, in which the early diggers, with the simplest tools, obtained for a short time large quantities of the coveted ore, seem now to be mostly exhausted. It is in the quartz formations of the mountain ranges, or in those at a great depth underground, reached by the sinking of shafts and regular mining operations, that Australian gold is henceforth to be chiefly procured. There are mines in Victoria 1000 feet deep, as at Clunes, and many others from 300 to 600 feet.

The copper mines of Burra Burra, in South Australia, proved very profitable some twenty-five years ago, yielding in a twelvemonth ore to the value of 350,000, and the Moonta mines, in 1872, were scarcely less productive. The province of South Australia, in that year, exported copper to the amount of 800,000. Queensland, in 1873, produced one-fourth that quantity. Tin, an article of great mercantile interest, is divided between Queensland and New South Wales in a frontier district, two-thirds of the extent of which belongs to the Darling Downs, within the last-mentioned province. There is a little tin, also, in some parts of Victoria. Lead, silver, and cinnabar have been obtained not only in New South Wales, but likewise in Western Australia.

The abundance of good iron ore, in convenient vicinity to thick beds of excellent coal, ensures a future career of manufacturing prosperity to New South Wales, and not less to Queensland. The country north and south of Sydney, and west of that city 100 miles inland to the dividing range of mountains, is all of Carboniferous formation. At the mouth of the Hunter River, from the port and town of Newcastle, coal was exported in 1873 to the value of 1,000,000 sterling. The collieries there taken up have an extent of 35,000 acres, but the area of the coal-field is officially estimated at 10,000,000 acres, and the seams are 9 feet to 1 1 feet thick. The quality of this coal is said to be equal to that of Great Britain for most furnace purposes, and it is generally used by steamships in the Pacific and Chinese navigation. Next in importance are the Wollongong collieries, south of Sydney, and those of Hartley, Maitland, and Berrima, now connected by railway with the capital.

In each of the places above named there is iron of a superior quality, the working of which to advantage cannot be long delayed. On the lllawarra coast it is found close to the finest bituminous coal, and to limestone. The iron of New South Wales is mostly haematite, and the ironstone contains from 60 to 70 per cent, of ore. Among other mineral products of the same region are cannel coal and shale yielding kerosene oil. This is a recognised article of export from New South Wales to the other colonies. It is hardly worth while to speak of diamonds, opals, and precious stones, but they are often picked up, though of small size, along the Mudgee and Abercrombie Rivers, and at Beechworth and Daylesford, in Victoria.

Climate. The Australian continent, extending over 28 of latitude, might be expected to show a consider able diversity of climate. In reality, however, it experiences fewer climatic variations than the other great continents, owing to its distance (28°) from the Antarctic circle and (11°) from the equator. There is, besides, a powerful determining cause in the uniform character and undivided extent of its dry interior plain. On this subject Mr Ranken, in his Dominion of Australia, remarks &quot;A basin having its northern portion in the tropics, it acts like an oven under the daily sun. It becomes daily heated ; then its atmosphere expands ; but such is its immensity that no sufficient supply of moist sea air from the neigh bouring oceans can reach it, to supply the vacancy caused by this expansion. Of an almost perfectly flat surface, there is no play for currents of air upon it; only the heat is daily absorbed and nightly radiated. Such is the heat, that in the summer the soil is more like a fire than an oven ; the air, if it moves, is Like a furnace-blast ; and such its ex tent and sameness, that as great heat may prevail hundreds of miles south as north of the tropics.&quot; This continual radiation of heat is sometimes relieved though not with the regularity of an annual season, indeed rather at uncertain intervals of several years by the admission of masses of vapour, drawn in from the Pacific or the Indian Ocean. Great masses of clouds, after labouring many months to reach the interior from the sea, succeed in passing over the sea-bound mountains, and spread themselves in floods of rain upon the inland country. The north-west shore, and that of Carpentaria, are favoured with an annual visitation of the monsoons, from December to March, penetrating as far as 500 miles into the continent, where the sands of the desert are driven in wavy heaps by the force of this wind. But South Australia, though it feels a cool sea breeze from the south-west, gets little rain, for lack of any mountain range parallel with the coast to arrest and condense the passing vapours. The yearly rainfall at Adelaide and Gawler is therefore not more than 15 or 20 inches, while at the head of Spencer Gulf it is but 6 or 8. In Victoria and in New South Wales, on the contrary, where a wall of mountain fronts the ocean, most places on the sea-board enjoy a fair allowance of rain. It is 32 inches at Portland, nearly 26 inches at Melbourne ; at Sydney and Newcastle, on the east coast, as much as 48 and 44 inches in the year. But at Brisbane, in Queensland, farther north, it amounts to 50 inches ; at Rockingham Bay, in latitude 18 S., where the hills are covered with dense forests, the rainfall in 1871 was no less than 90 inches. In every part, however, of this magnificent highland region, the supply of moisture is rapidly diminished by passing inland ; so that very little remains to fall on the interior or western slopes of the coast ranges, and to irrigate the interior plains.

With regard to the temperature, the northern regions of the continent being situated within the tropic of Capricorn,