MOVING ANTICYCLONES. 



Taking individual anticyclones in Australia the slowest moved 

 at one hundred and twenty miles per day, and the quickest nine 

 hundred and fifty miles per day, the average being four hundred 

 miles per day. The result of this comparison surprised me by 

 the similarity of the two results. I do not, however, think that 

 very much value should be attached to a comparison of barometer 

 curves for one year only, still it agrees remarkably with that 

 obtained by four and three-quarter years' results for Australasia, 

 and the little difference is in the direction it ought to be, owing 

 to the obvious friction of the land surface, mountains, etc., as 

 compared with the smooth sea surface. 



The two methods of determining the velocity of anticyclones, 

 that is, over Australia alone, where it is four hundred miles per day, 

 and over the space from Natal to Sydney, where it is four hundred 

 and fifty-eight miles per day, seem to leave no doubt as to their 

 persistence. For if they can thus be followed one-third of the 

 circumference of the earth, i.e. from Natal to Sydney, it may 

 safely be assumed that they travel the other two-thirds of the way, 

 and that they keep up their general characteristics. What 

 influence that great obstacle in their path, the Andes of South 

 America, may have on them I am not at present in a position 

 to say, but I have no doubt, from what we see so clearly in the in- 

 fluence of our own comparatively small range of mountains along 

 the east coast of New South Wales, that it is a very material one. 



If from Buenos Ayres we could get by cablegram the state of 

 the weather from day to day, we should be in a position to 

 forecast the coming weather for about a month in advance ; and 

 it may yet be that when our investigations, which are now in 

 progress, are completed we shall be able to forecast far longer 

 periods. If, for instance, we could ascertain the velocity of the 

 translation of the anticyclone round the other two-thirds of the 

 globe, ;is we have done for the one-third from Natal to Sydney, or 

 rather more than one-third because it extends to New Zealand, 

 then we could ultimately forecast the return, in say, seven weeks, 

 of weather passing over Sydney. Certainly the discovery of the 



