Page:Encyclopædia Britannica, Ninth Edition, v. 3.djvu/124

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110
AUSTRALIA
[botany.

resemble the parts of South America and South Africa, that are situated in corresponding latitudes. The sea ward districts of New South Wales seem in this respect to be like Southern Europe. The mean annual temperature of Sydney is 62° 4′ Fahr., almost equal to that of Lisbon in Portugal. The inland plains of this colony, how ever, west of the Blue Mountains, which suffer much from evaporation, experience in summer a heat which rises to 100° Fahr. in the shade, and sometimes as high as 140°. There are highland districts, on the contrary, such as Kiandra, 4640 feet above the sea-level, where frost, snow, and hail are endured through the winter. On the Australian Alps, cold being more intense in the dry air, the limit of perpetual snow comes down to 7145 feet. The days on which rain falls in the coast regions of New South Wales average from 100 to 150 in the year, and the amount from 20 inches to 50 inches, decreasing generally farther inland.

In winter, in New South Wales, the prevalent winds blow from the west, with occasional storms of wind and rain from the eastward ; while the autumn months have much cloudy weather, not accompanied by rain. January and February are the hottest months of summer, and July the coldest month of winter. With regard to the climate of Victoria, Mr Robert Ellery, Government astronomer at Melbourne, in his report of 1872, furnishes exact information. The mean annual temperature at Melbourne during fourteen years was 57 6, and that of the whole province 5 6 8, including stations 2000 feet or 1400 feet above the sea-level at Daylesford and Ballarat. This is equivalent to the mean annual temperature of Marseilles and Florence, in the northern hemisphere, but the climate of Melbourne is much more equable than that of the Mediterranean shores. The lowest temperature yet recorded has been 27, or 5 below the freezing point; the highest, 111 in the shade, occurring during one of the hot winds, called " brickfielders," which, loaded with dust, occasionally blow for a few hours in summer. At Sandhurst, 778 feet above the sea, the greatest extremes of temperature yet observed were 117 and 27 5; at Ballarat the extreme of winter cold was 10 below freezing.

The amount of humidity in the air is liable to great and rapid variations in the summer months. It is some times reduced as much as 60 per cent, within a few hours, by the effect of hot dry winds. But this is compensated by an access of moisture upon a change of wind. The annual average rainfall at Melbourne, which for thirty years is stated at 25 66 inches, does not seem less than that of places in similar latitudes in other parts of the world. Yet it proves inadequate, because of the great amount of evaporation, estimated by Professor Neumayer at 42 inches.

The spring season in Victoria, consisting of the months of September, October, and November, is genial and pleasant, with some rain. The summer December, January, and February is generally hot and dry, though its first month is sometimes broken by storms of cold wind and heavy rain. In February the north winds assume the character of siroccos, and bush-fires often devastate the grassy plains and forests of the inland country. The autumn months March, April, and May are, in general, the most agreeable; and at this season vegetable life is refreshed, and puts forth a growth equal to that of the spring. The winter is June, July, and August, with strong, dry, cold winds from the north, alternating with frequent rain from the opposite quarter ; there is little ice or snow, except in the mountain districts.

Botany. A probable computation of the whole number of distinct vegetable species indigenous to Australia and Tasmania has been made by Baron Ferdinand von Miller, the Government botanist at Melbourne. He believes that, omitting the minute fungi, there will not be found above 10,000 species of Australian plants. The standard authority upon this subject, so far as it could be known sixty years ago, but now requiring to be completed and extended, was the Prodromus Floræ Novaeæ Hollandice, published in 1810 by Mr Robert Brown of the British Museum. Besides making personal observations from 1802 to 1805, he had classified the collections procured by Sir Joseph Banks when Captain Cook's ship visited the eastern shore. Upon that occasion, in 1769, the name of Botany Bay was given to an inlet near Port Jackson, from the variety of new specimens found there. Baron von Müller's Report of 1857 on the researches made by him alone in the North Australian exploring expedition under Mr Gregory, exhibits 2000 new species, representing more than 800 genera, which belong to 160 different orders. He could discover no new natural order, or fundamental form of the vegetable kingdom, in a minute examination of the flora of Arnhem Land, the country around the Gulf of Carpentaria, and the Victoria River, but 60 genera were found that had not been noticed by any earlier Australian botanist.

The eastern parts of this continent, New South Wales and Queensland, are very much richer, both in their botany and in their zoology, than any other parts of Australia. Much was done here for the former science, half a century ago, by Mr Allan Cunningham, whose monumental obelisk fitly stands in the Botanic Garden at Sydney. In general, the growth of trees on the north and north-west coasts is wanting in size and regularity, compared with their growth in eastern Australia. To the last-mentioned region, for instance, the pines are entirely confined; here the Moreton Bay pine, and Bunya Bunya pine, of the genus Araucaria, growing to 150 feet in height, yield excellent timber. The red cedar, the iron bark, the blue gum-tree, and others useful to the carpenter, belong likewise to the eastern highlands. The Casuarina, or she-oak, is found on the shores of Carpentaria and in the interior, but not on the banks of the Victoria River to the north-west. Of the Eucalyptus, or gum-tree, Australia has 400 species; but the one most uniformly distributed is the Eucalyptus rostrata or acuminata, called the flooded gum-tree ; its timber is durable, and takes a fine polish. Rosewood, tulip-wood, sandal-wood, and satin-wood, with other materials for the cabinetmaker s ornamental work, abound in the forests of Queensland. The forest scenery of the more northerly districts, within the tropics, and onwards to Rockingham Bay, is described as of great luxuriance. It consists of many kinds of large umbrageous trees, some of an Indian type, intermixed with noble araucarias, all matted together in an impervious thicket by lianes of the convolvulus, the calamus, and other plants, climbing or pendent, harbouring in their shade many parasitical orchids and ferns. Such forests overhang the seaward sides of the mountain ranges, where they inhale abundant moisture from the winds of the Pacific Ocean, and feed upon a congenial soil from the decomposition of schistose rocks.

A striking contrast is offered to the view beyond the coast ranges. The interior of Queensland presents either high land downs of basaltic origin, almost bare of trees, but with abundant herbaceous vegetation, good pasture grass, and an immense quantity of vervain, or the Brigalow scrub, merely shrubs and small trees, on a soil of argillaceous sandstone. The sandstone table-lands, again, naked and dry, produce but a few diminutive eucalypti, and sparse tufts of uneatable grasses, while the inland deserts have only the acacia to break the monotony of the scene. The character of the inland flora adds confirmation to the

belief that the interior was formerly a marine soil, which