RESIDENTIAL ADDRESS. 439 
the knowledge of other places not at our actual door that we teach in geography, 
how to get there, what to find when we get there, and so forth. The greatest 
revolution that is being worked in human life is the elimination of distance, 
and this elimination is going on apace. It is entering into every phase of public 
and private life, and is changing it more and more. The most difficult and 
dangerous of all Imperial problems at this moment is the colour problem, and 
this has been entirely created by human agency, scientific agency, bringing the 
lands of the coloured and the white men closer together. Year after year, 
because distance is being diminished, coming and going of men and of products 
is multiplying; steadily and surely the world is becoming one continent. This 
is what I want geographers to note and the peoples to learn. Geographers have 
recorded what the world is according to Nature. I want them to note and 
teach others to note how under an all-wise Providence it is being subdued, 
replenished, recast, and contracted by man. 
MELBOURNE. 
FRIDAY, AUGUST 14. 
The following Papers were read :— 
1. Australian Rainfall. By H. A. Hunr, Commonwealth Meteorologist. 
The main factors to be considered in relation to the controlling causes of 
rainfall in Australia are the south-east and westerly trade winds, the 
monsoonal and southern depressions, cyclones from the north-east and north- 
west tropics, locally formed cyclones, and the anticyclones, in conjunction with 
the modifying effects on these various atmospheric movements of the physical 
features of the different parts of the country. 
Around the central dry area of Australia the isohyets describe somewhat 
concentric curves, the modifications being mostly due to variations in elevation. 
Thus, the Darling Ranges to a great degree account for the rainfall of the 
south-west corner of the continent. The Flinders Range (South Australia) 
and Australian Alps in the south-east have a heavier rainfall than the surround- 
ing tracts owing to their cooling effect on the air-currents. Along the eastern 
elevated margin of the Commonwealth the ridges between large river-valleys 
also account for an enhanced precipitation. Examples of the latter type are the 
Peak Range and Darling Downs in Queensland, where the eastern ranges of the 
northern parts of that State obstruct the south-east trade winds and cause 
our heaviest rainfall. In Western Tasmania there is an excessive rainfall for 
similar reasons, though there the westerly trades are the moisture-laden winds. 
During the hotter months, November to April inclusive, the northern parts 
of Australia are wet and the southern dry, and in the colder months, May to 
October inclusive, the southern parts are wet and the northern dry, while over 
the eastern areas of the continent the rainfall is distributed fairly generally 
throughout the year. 
The southern portions of the continent, where the precipitations are con- 
trolled by the ‘ stormy westerlies,’ southern cyclones and V-shaped depressions, 
enjoy very consistent annual totals, but north of the tropics, and in fact in all 
parts of the continent subject to monsoon rains, the departures from the 
normal are occasionally very great. 
When the monsoonal disturbances are in evidence, the effect of the rainfall 
on the country generally and the economic results for the succeeding season 
are very pronounced. The interior of the continent becomes transformed. 
The plains, which ordinarily have an intensifying effect on the heat winds 
of the summer, are deluged with rain, and respond immediately with a luxurious 
growth of grass and herbage. The air is then both tempered in heat and loses 
its dryness for considerable periods. 
The monsoon region comprises the whole of Australia north of the Tropic 
of Capricorn, together with Southern Queensland and the north of New South 
Wales. The heaviest rains are in January and February. They are directly 
