Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/438

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408 NEW SOUTH WALES which is about 700 miles in length, extends from Cape Howe (37 30 ) at the south-eastern corner of Australia to Point Danger in 28 7 S. The colony is approximately rectangular in form, with an average depth from the coast of 650 miles and an average width from north to south of 500 miles. The superficial area is estimated at 310,000 square miles, or about one-tenth of the whole of Australia. Along the seaboard are twenty-two well-defined head lands or capes and about a score of bays or inlets, to mark which for navigators there are twenty- three lighthouses. There are four very fine natural harbours, viz., Jervis Bay, Port Jackson, Broken Bay, and Port Stephens, and several others of minor importance. Of these, only Port Jackson, on which is situated the city of Sydney, has attained as yet to commercial importance. The port second in com mercial importance is Newcastle, at the mouth of the Hunter river, which is the great coal-shipping port of the colony. Secondary harbours, available for coasting steamers, south of Sydney are to be found at Port Hacking, Wollongong, Kiama, Shoalhaven, Bateman s Bay, Ulladulla, Merimbula, and Twofold Bay. To the north of Sydney the secondary ports are at the mouths of the Hawkesbury, the Manning, the Hastings, the Macleay, the Nambucca, the Bellinger, the Clarence, the Richmond, and the Tweed rivers. These are mostly bar harbours, but the Clarence is a noble river, and when the entrance is im proved will become a great port. The characteristic natural feature of New South Wales is the great Cordillera range running north and south. The average elevation of this range is about 2500 feet. The highest point, Mount Kosciusko, reaches, however, a height of 7300 feet, about 700 feet below the theoretical line of perpetual snow, yet snow has never more than once wholly disappeared. None of the interior parts of the colony attain to a similar elevation. This range runs generally parallel to the coast, varying from 30 to 140 miles distant, being nearest at the south and receding the farthest at the sources of the Goulburn river, the main tributary of the Hunter. The crest of this range is in some places narrow ; in others it spreads out into a wide table-land. The eastern slopes are somewhat rugged and precipitous, the sandstone especially being deeply fissured by the watercourses; but along the greater part of the coast there is a belt of flat land generally of high fertility. At the outlet of many of the streams descending from the range are large lagoons, sometimes closed against the sea by sandbars, and at other times opened by the force of the outrushing waters. The principal of these are Lake Illawarra arid Lake Macquarie, Tuggarah Lake, Lake Myall, Wallis Lake, Watson Taylor Lake, and Queen s Lake. Lake Macquarie, however, is rather a magnificent estuary than a lake, and if the bar at the entrance could be removed would become a commercial port, as the hills at the back are rich in coal. The inland lakes are few and unimportant. They are mostly shallow and occasionally dry. On the western side of the main range the general slope of the country is towards the west, the drainage being into the Murray, the Murrumbidgee, the Lachlan, and the Darling ; but the drainage of all of them unites in the Murray, at the town of Wentworth, near the south western corner of the colony. Climate. The rainfall differs very much in different parts of the colony. It is heaviest on the eastern coast, where the easterly gales break against the main range. Here the average is 40 inches on the south to 65 inches on the north. Sydney, with forty-three years observation, has a mean of 50 inches. In winter the temperature sometimes falls to the freezing point, and it rises in summer to 85 or 90 on very hot days. The mean temperature of Sydney is 62-5. On the table-lands the rainfall is from 20 to 35 inches. In winter the temperature in extreme cases falls 10 or 15 below the freezing point, and in the height of summer it rises to 100 or 105. The mean temperature may be found from 50 to 60. On the great western plains the rainfall is much less, falling rapidly as the high land is left to 18 inches, and in the far west to 8 inches. Here the temperature seldom falls more than 6 or 8 a below freezing, but in summer it often rises to 110, and in extreme cases to 120; and the mean temperatures range from 60 on the south to 68 on the north. Along the coast-line the air is moist and soft ; the temperature is- mild, the thermometer ranging from 78 in January to 59 a in July, and the mean for the year being about 62^. The prevailing wind in summer is from the north-east, though occasionally hot, dry winds come from the north-western interior, which are generally followed by a sudden and violent reaction from the south, known as " southerly bursters." On such occasions the thermometer will some times suddenly fall in a few hours 20 or 30 degrees. The violent rainstorms generally come from the east, shifting from north-east to south-east ; but, as they are mostly accompanied with a high temperature, their origin is to be looked for towards the north. During the winter months the wind blows mostly from the west. It is a dry wind, and the weather is generally clear, bright, and invigorat ing. On the table-land the air is much drier than on the coast, the winters are longer and colder, and the summer heat, except in the middle of hot days, much below the coast temperature; and this elevated region is much resorted to by the citizens of Sydney as a summer resort. As the country slopes down towards the west the dryness of the climate increases. Though the heat is sometimes oppressive, the climate is not unhealthy ; while sheep and cattle are more free from disease here than in moister parts of the colony. Geology. The main mountain chain, running north and south, with the eastern portion of the continent generally, must have been submerged during the early Miocene period to the extent of about 4000 feet below its present level, leaving the highest portions of the range standing; out as islands, which have probably never wholly been submerged since the commencement of the Mesozoic era, and to this is attributable the survival of the cycads, araucarias, and other ancient vegetable forms which now abound in Australia ; the living Ceratodus forsteri of Queensland, and the Marsujiialia, also point to the same, conclusion. To the westward it throws out many lateral spurs, diminishing gradually in elevation, and determining the basins of the tributaries of the rivers flowing westward. The most important of these lateral ranges runs north westward towards the Darling and beyond to the Barrier Ranges in the north-western part of the colony. The summit of this lateral range has been partly denuded, and it dips towards the plain of the Darling where that river cuts through it. This being the only water channel from all the north-western portion of the colony, all the tributaries of the Darling converge into this depression. This range divides the western portion of the colony into two main basins, the northern of which contains all the affluents of the Darling, and the southern is the Murrum bidgee basin, with its affluents the Murray and the Lachlan. These basins consist of a large Cretaceous area, which extends away far beyond the western boundary of the colony. The basis of the mountain system of the colony is granite, and the oldest sedimentary deposit rest ing on it is the Upper Silurian. In the neighbouring colony of Victoria, Lower Silurian fossils are found over a large area west of Melbourne, but in New South Wales nothing has been definitely determined older than the Upper Silurian. Granite has lifted the superincumbent