F. B. GUTHRIE. LXV. 
taken in the selection of such crops as are most capable of 
resisting the action of these salts. This, combined with a 
system of drainage wherever practicable, good tillage, and 
the use in some cases of substances known to correct the 
alkali, such as gypsum on the soil or in the water, will, I 
think, enable us to utilise such water with advantage on 
these soils. 
I have endeavoured to lay before you the chief points 
which are to be considered in any scheme by which it is 
proposed to render farming profitable on this class of soil 
by the aid of irrigation, whether with river or with artesian 
water, and have directed your attention to the dangers 
which are to be avoided. With a knowledge of these 
dangers, and of the means for combating them, there should 
in my opinion, be no difficulty in the application of irriga- 
tion, but if the water is applied without some appreciation 
of the problems of soil chemistry and soil physics, I am 
convinced that much disappointment and much actual 
failure will be experienced. 
From the chemical point of view discussed in this paper, 
there is no room for doubt that the soils of our arid districts 
are admirably adapted for cultivation by means of irrigation, 
abundance of water properly applied, being the only thing 
necessary to render them extraordinarily fertile, and it is 
in the establishment of co-operative irrigation colonies, 
such as exist in similar arid districts in other parts of the 
world, notably in the Western States of America, that we 
may look forward confidently to an expansion of our agri- 
cultural resources hitherto undreamed of. 
5—July 20, 1903. 
