NATURE V#RSUS THE AUSTRALIAN. 
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tropics in both hemispheres. (See Fig. A.) ‘These are the regions 
where the trade winds are supreme; and where they blow from the con- 
tinents to the ocean they are desiccating winds. Their realm covers 
half the surface of the globe, and where a broad belt of land is affected 
(as in Australia and Northern Africa) the result from an economic 
point of view is well-nigh disastrous. rm 
Here, then, is the first and the chief burden which Nature hag laid | 
on the Australian. Nothing can make up for the large extent of our. 
continent which lies below the constant sweep of the desiccating trade 
winds. It is no help to know that in fairly late geological times the 
continent extended into more clement regions to-the south and east 
where the climate was undoubtedly better suited for closer settlement. 
( 
<P @ | 
Musgrave a \. 
2. 
\ : 4 
: \. Flinde a5 
Cue Ne Milena ‘ Na 
SY - 1 t 
\ Kosciusko 
S$: a J 1 
FIG. B. 
The figures show the number of months with an averaze wet bulb over, 70° F. 
The black areas are over 2,090 feet above sea-level. fea, 
In Cretaceous times our land probably extended from Adelaide to 
Macquarie Island and New Zealand. . Moreover the trade wind belt 
was interrupted by a great sea (extending from the Bight to New. 
Guinea), in which were deposited our well-known artesian water-bearing 
_ strata. At this date the Western Australian interior (now a desert) * 
was almost certainly visited by constant rain-bearing winds, and the 
* Desert in the geosraphical sense is country receiving less than 10 inches of rainfall, and at best 
. capable only of sparse pastoral occupation. 
461 
