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A Fe^at Remarks About Weather Fore- 

 casting FOR South Australia. 



'Bj W. EnNEST Cooke, B.A., Acting GrovernmeiLt xlstronomer. 

 [Read Sept. 8th, 1885.] 



The comparatively recent science of meteorology has ad- 

 vanced sufficiently far to become of considerable practical 

 benefit to mariners, farmers, and all those whom the question 

 whence tbe storm cometh and whither it goeth vitally affects. 

 Having recognised the great strides that have lately been 

 made, a number of persons seem to think that now it is a 

 comparatively easy matter to forecast coming weather for one 

 or two days ahead with absolute certainty ; and, in fact, 

 several letters and articles have appeared recently in various 

 colonial papers taking up this view of the case, and causing 

 many to wonder why, under the circumstances, reliable 

 weather forecasts are not issued in the daily papers. I wish, 

 in these remarks, to place before the Society a few considera- 

 tions as to the reasons why such a desirable result cannot at 

 present be brought about, as far as South Australian weather 

 is concerned. 



The manner in whicb a number of the aforementioned 

 articles refer to this matter indicates a misconception. They 

 liken the approach of a cyclone from the westward to the 

 advent of a railway train whose times of passing the successive 

 stations are duly telegraphed. It passes Albany at a given 

 time, Esperance Bay some hours later, and Eucla a certain 

 number of hours later still. Now we have only to make a very 

 simple calculation in order to find out the exact time it will 

 pass, say Adelaide. The only meteorological reports that are 

 necessary are those from, say, Albany, Esperance Bay, and 

 Eucla, and all within reach of a daily newspaper ought to be 

 informed with absolute certainty of the state of the weather 

 two or three days ahead. Yet this is not done. Why ? 

 Possibly there are one or two premises, stated or inferred, in 

 the above argument that are to a certain extent unsound. 

 Eirst of all, we say a depression passes Albany at a certain 

 time. Who is to tell that ? I suppose Albany is one of the 

 most impossible places in the world to state with any certainty 

 that a depression has passed eastwards. The winds there seem 

 to be almost always westerly, so they can be no guide to the 

 direction of the central depression ; and the barometer is so 

 differently affected there from other places along the coast that 



