Art. XVIII. — Notes on the Rainfall Map recently Issued 

 by the Government of Victoria. 



By Mr. Ellery, F.RS. 



[Read 15th November, 1883.] 



The subject of rainfall is one of great importance to 

 almost every community, and perhaps to none much more 

 than to Australia, where " prosperity" or "poverty" is almost 

 synonymous with its plenteousness or its paucity. There is, 

 therefore , a constant anxiety in the public mind regarding 

 the prospects of rain or of wet and dry seasons, and a wide- 

 spread interest in the monthly and annual amount of rain 

 that falls on the various areas of which settled Australia is 

 composed. No amount of knowledge of this subject nor 

 any human interference are likely to tangibly affect the 

 amount of rain which nature provides for these regions ; but 

 an accurate knowledge of the amount provided, and its 

 distribution both as regards area and time, are of the utmost 

 importance and value, as showing on the one hand how 

 much may naturally be expected to fall over any particular 

 area or areas, and when ; and, on the other, the provisions 

 necessary to turn what does fall to the best account. Over 

 a large part of the littoral areas of Australia rain falls every 

 year on an average equal to that in the neighbourhood of 

 London ; but it is not so equally distributed over the year as 

 in that place. Moreover, England generally, by reason of 

 the immense influence of the " Gulf Stream," possesses an 

 extremely humid climate, while Australia, for the most part, 

 is extremely dry. Although, therefore, the actual rainfall be 

 the same, these differing conditions make up a vastly 

 different climate. With our dry atmosphere the same 

 amount of rain does not "go near so far," and it has been 

 gradually forced upon us that to make it go far enough for 

 our needs we must not allow it to flow back to the sea with- 

 out spreading its beneficence a little more widely over our 

 thirsty but otherwise prolific soil. To obtain a good know- 

 ledge of our assets in this respect, the Governments of all 

 the colonies have for some years past been spreading rain 

 gauges over Australia, and gathering statistics from many 

 hundreds of places, and the number is largely increased 



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