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notliing of the vaster land of Australia) I should expect at 

 Hobart Town a turning of this westerly wind northward, 

 drawn towards the heated land, i.e., I should expect it to 

 blow from the the S.W. For the converse reason, in the 

 winter months I should look for the N.W. What are the 

 facts ? If we examine our own statistics, extended over 30 

 years, we do find the N.W. prevailing during the winter, 

 but though the S. W". seldom or never prevails, yet the south 

 wind more or less modifies or overcomes the usual westerly 

 wind for the summer months, especially in January and 

 February. But what is the reason for the frequent preva- 

 lence of an east wind in the summer months in Bass' Straits 

 helping on the " Pioneer " on its outward voyage to Circular 

 Head ? The situation of our island at the extreme S.E. of 

 the Continent so that it may almost be regarded as a 

 continuation of the east coast of Australia, leads me 

 to refer this easterly summer wind to the indraught of the 

 wind from the sea to the east coast of Australia, felt, as I 

 have shown, in summer at Sydney. But why it behaves like 

 a deadly sirocco, as it beats upon the promontory of Circular 

 Head, blighting the fruit trees and cabbages, and producing 

 feverish heat and determination of the blood to the head, 

 inflammatory attacks, opthalmia, and I know not what 

 besides, isaproblem for which I have no satisfactory solution to 

 offer. I will draw your attention to another peculiarity of our 

 local winds. When the hot blasts of Australia reach our 

 island (which happily is of rare occurrence) they pass over 

 the northern and midland portions and precipitate themeselves 

 upon the southern coasts. I do not know whether any 

 explanation of this peculiar phenomenon has been given. I 

 apprehend, however, the true solution is to be found in the 

 analogy of everyday occurrence on a larger scale within the 

 tropics in their relation to the poles. The heated land of Aus- 

 tralia heats in turn the air, and expanding its bulk, lessens its 

 specific gravity, and causes it to ascend. The air over the 

 Straits would rush in to supply the deficient pressure at the 

 surface, while the ascending lighter column would pass south- 

 wards, until when sufficiently condensed and heavier, it would 

 descend to the lower, stratum. This crisis of equalised 

 temperature seems to occur when the upper stream of heated 

 air approaches our southern coast, and meets our colder 

 southern ocean. Strzelecki observed that while the hot wind 

 blew from the north at the top of Ben Lomond, 5,000 feet 

 high, it was not felt 2,000 feet bigh on the windward side of 

 the same mountain. 



But I wish to interest the Society not so much with the 

 wind as with the whirlwind — not the zephyr but the storm. 



