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30 are so obtrusive that they cannot be overlooked, and they are welcomed as the most pleasant relief after the high temperatures and oppressive northerly winds which precede them. They come in the late spring, all summer, and part of autumn, but as a rule, in order to get a strong southerly an antecedent excessively hot day or days must be experienced. The duration of a southerly burster may be anything from two hours to ten days, but it is not to be understood that the term burster is applied to the whole period or duration of the southerly wind. What is called a burster is the squall or sudden and violent change of wind direction, and the violent rush or "burst" which marks the advent of this wind. We need not go into all the characteristics; these will be found in the Abercromby Prize Essay on this subject. It is there explained that the south wind comes in front of an approaching anticyclone, and that it is felt from West to Eastern Australia, but it is only on the eastern coast, where, aided by the smaller friction of the ocean and the shelter which the mountains afford from other winds, that the southerly becomes more vigorous and rushes northwards in a squall, which happens so suddenly and with such force, that at times ships drag their anchors in Sydney harbour.

It is not definitely made out yet that these storms are ever "line storms" in the sense that the change of wind comes as the dip in the isobars passes over each place in succession, but there are many facts which suggest that such is the fact in some instances. Our present purpose is to describe a "burster" as a type of Australian weather. The essential feature of it is a sharp &Lambda; in Chart 31 such a depression is shewn existing over Victoria and Tasmania, with its axis lying from north-north-west to south-south-east. An anticyclone of good energy for this time of the year exists to the west, and hot northerly winds occupy northern Australia; these are the elements for the good burster that followed. As a general rule, the position and character of two