Page:A sketch of the physical structure of Australia.djvu/95

83 This hot wind always blows from the interior of the country. In New South Wales and Tasmania it blows from the N.W. and rarely lasts more than two days. It is generally succeeded by a sudden squall from the southward, which brings up clouds and often rain. During the hot wind the thermometer rises to 100&deg; or even 115&deg; in the shade, but with the southerly squall there is sometimes a sudden fall of full 40&deg; in the course of a half or even a quarter of an hour. Near Port Phillip the hot wind comes from the north or even the N.E. the hot stream being probably deflected by the high lands of the Eastern Chain. In South Australia the hot winds come from the north, and sometimes continue as long as nine days. Many of the houses in Adelaide have double walls with a space between on their northern sides to ward off some of its influence. The longer duration and I believe the greater intensity of the hot wind here is evidently due to the close proximity of the central desert and that the mountain chains, such as they are, run parallel to the course of the wind and thus do little if anything towards sheltering the colony from its influence. In Western Australia the hot wind, or as it is there called the "land wind," blows from the N.E., but from my own experience, though sufficiently parching, they have not the fierceness and intensity which they have in Southern and Eastern Australia. Captain King describes somewhat similar effects on the N.W. coast, as arising