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noticed that perpendicular whirlwinds were of common occurrence during the prevalence of southerly winds. These spiral currents are usually from about 15 to 30 feet in diameter ; they carry up the dust and fine sand to an immense height, and look like dirty brown-coloured moving columns; sometimes they travel on singly, at others they are in companies of three, four, or more. After a time they lose their perpendicular, and gracefully descend to the earth, when they look like falling towers ; as soon as the upper ends of the columns near the earth, the rotatory motion ceases, the dust falls to the ground, and the pillars vanish into thin air. Occasionally a whirlwind will spring up in a moment, carry a cloud of dust into mid-air, and then suddenly cease.
The heat and moisture of the atmosphere of course vary in different parts of the country. In the deep seated mountain ravines, the climate approaches to that of Britain. The thermometer in the shade seldom ranges above 85° Farh., never exceeds 90°, and throughout the winter, frosty nights and snow-storms are common: the rays from the morning sun, however, generally melt the ice. The inhabitants of these hilly districts occasionally suffer from colds and rheumatic affections. I remember sitting on one of these mountains in South Australia, enjoying the clear, balmy breeze, my thermometer 81° in the shade, while beneath my gaze Adelaide and the plains around, were smoking in the dust and scorching blast of a hot wind, the thermometer there being in the shade 107° Farh. In the mountain districts a greater quantity of rain falls than on the plains, the air is elastic and bracing, the hot winds are scarcely felt, and, in truth, the climate is altogether much more suitable to the constitution of an Englishman than that of the plains. The chemical nature of the atmosphere has not been ascertained ; I believe its peculiar properties to be tenuity, and extreme dryness. It is usually so clear, that the edges of distant objects appear sharply carved out, houses miles away seem near at hand, and the hills and forests at the extremity of vision actually seem painted on the horizon. On the plains the atmosphere is rarely humid, except when it rains; fogs, to the best of my knowledge, never occur ; and mists not oftener than once in a year, and then only for a few hours. Dews, however, are not uncommon in the winter, in the early spring, and the late autumn months. They become perceptible before nine in the evening, when the atmosphere is perfectly serene. The colonists are not afraid of exposure to them, although, to my knowledge, fever and rheumatics have sometimes been the result.
In the vicinity of Sydney long, protracted droughts are of occasional occurrence; but the position of the colonies on the southern coast insures them copious rains: scarcely a month passing without more or less falling.
The heaviest showers are in the winter ; they occasionally pour down in continuous torrents, flooding the country, and filling the water
courses with rushing streams, that move on with the speed and the might of a cataract, snapping ancient trees and sweeping down every obstruction.
Violent thunder-storms, I should say hurricanes, sometimes visit the provinces. They are usually preceded by the gathering of a deep, dense, lowering bank of clouds, generally in the southward: the atmosphere becomes still, heavy, dead, hot, and close almost to suffocation ; the breathing of a gentle breeze, and the gradual advancing nearer and nearer of lightning and thunder, indicate the immediate approach of the storm. At length the wind bursts into the full crash of the hurricane, tearing down trees, carrying away portions of houses, bursting in glass-windows, and filling the air with dust and sand; vivid flashes of lightning dart from the deep black heavens in every direction, the rain pours down in floods, and the plains are shook by loud, sharp cracks of thunder, which vibrate from mountain to mountain with awful sublimity. Frequently, after a heavy peal, there succeeds a minute's interval of death-like stillness; the wind is hushed, the rain ceased, and all is silent, when suddenly down pours a mighty torrent of rain, again the wind bursts out with irresistible violence, the lightning flashes, and the heavy thunder rolls on in continuous roar, which is only silenced by the sudden and tremendous crash of some peal near at hand, which bursts on the ear with awful violence, and strikes the heart with awe. These commotions are of varied continuance, sometimes they last for twenty-four, or even thirty-six hours; at others, within an hour after the outburst, the thunder-clouds disappear, the sky becomes serene, and the sun shines out through the clear air with dazzling bright