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strength covering the southern colonies of South Australia and Victoria, and the greater part of New South Wales; its isobars are unusually symmetrical and its rain influence the most extensive we have on record. During the 29th and 30th rain continued to fall over considerable areas, although on the 30th the depression filled up and the storm was displaced by the high pressure coming on from the west.

TYPE XIII.—WESTERLY WINDS.

The Winter anticyclone (See Chart 36) is much more extensive than the Summer one, and its grades are steeper and circulation stronger, while its latitude is further north, often up to 30° S.; hence the circulation on its southern side, unlike the Summer one, affects the mainland of Australia and gives us our westerly winds. And just as the trade wind intensifies its northern circulation by adding force thereto, so the brave west winds of the southern ocean follow the general move of the weather systems northwards, and thus add force to the westerly circulation of the anticyclone, and its greater dimensions increase the size of the &Lambda; depression, so much that it no longer has the sharply defined change from