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science upon the ultimate causes of the existing state of things? Are we not in the 
position of an anxious physician who is trying to cope with an obscure disease; he 
must apply his remedies more or less empirically? But, nowadays, medical men are 
trying to get at the origin of disease, at the pathogenic organism that causes it, at the 
conditions which promote its growth or retard its development, and treatment and 
preventive steps are based upon knowledge as far removed from empiricism as 
possible. 
As regards the bacillus of the drifting sands of the interior, Heaven preserve me 
from the presumption that I have discovered it, or that I am able to suggest a wholly 
satisfactory remedy; but if the scientific men of this State will give attention to the 
subject, and systematically make observations and collect data, I do not doubt that the 
drifting sands of New South Wales will be kept under control. 

2. Area of Sand-drift Country. 
The sand-drift country extends in its greatest intensity from our western boun- 
dary to the Darling. To a lesser degree it includes most of the Cretaceous and Cainozoic 
territory of our geological maps. Reference may be made to the Vegetation Zones 
Map of New South Wales published by me in the June, 1906, issue of the Agricultural 
Gazette. Much of the country marked 6 in that map is liable to sand-drifts. 
Photographs of the Gin-bottle, Goonery Sand-hills on the Bourke-Wanaaring 
Road, will be found at Vol. IV, page 155, of the present work, together with a f6w 
explanatory remarks. 
3. Classification of Western Soils. 
The Western country may be divided into three classes : 
(a) The black earthy plains (the " black-soil plains ") which crack when dry, but 
which do not move. 
(b) Soil with more or less clay in it; this may blow away, but it does not drift. 
Much of this country is subject to inundation during high floods. 
(c) Drifting sands. The soil is composed of clay, vegetable matter, and sand. 
The lighter component parts blow away during seasons of extreme drought 
when the surface is denuded of vegetation. The remaining sands mostly red 
in colour, but sometimes white are the drifting sands of tke west. 
4. Geological Origin of the Moving Sand. 
Where does it originate ? In Central Australia, extending further towards the 
west than towards the east of the continent. As far as our own State is concerned, the 
Barrier and Grey Ranges arrest the great bulk of the sand tending to come from South 
Australia, and the Murray River performs a similar service in regard to the desert 
country in Victoria. In other words, our trouble has originated within our own borders. 
