436 T. W. E. DAVID. 
mentioned, would irrigate only seven hundred and fifty acres.. 
Still the question of irrigation from artesian wells is an important. 
one, as it affords the means of producing fodder and other crops 
on a moderate scale at intervals through a large district which is 
badly provided with surface water. The cost of artesian water is 
another point on which there is much misapprehension. Ifa flow 
of three cubic feet per second, or 1,620,000 gallons per day, were 
obtained from an artesian well at a cost of £3,000, the result. 
would be considered very satisfactory. If interest on the outlay 
be taken at six per cent. this would make the cost £60 per annum 
for every cubic foot per second. This is just double the rate at. 
which it is estimated that water could profitably be supplied by 
the proposed Murrumbidgee Southern Canal. With reference to 
a remark of Mr. J. Wilson of Dunlop Station, on the river Dar- 
ling, Mr. McKinney pointed out that a study of the conditions 
existing on the higher parts of the catchment areas of the tribu- 
taries of the river Darling, shows that there is nothing in regard 
to either the volume or the pressure of the artesian flow which is 
not easily accounted for. The elevation of the higher parts of 
these catchment areas and the rainfall are sufficient to account 
for a much larger quantity of water than has yet been struck. 
Regarding the danger of the spread of a salty efflorescence by the 
water used for irrigation, while such a danger undoubtedly exists, 
whether the source of the salts be the water or the soil, many state- 
ments publicly made with more or less authority, have certainly 
given an exaggerated idea of this danger. During a considerable 
part of Mr. McKinney’s service in the Irrigation Department in 
India, he was in districts which suffered much from the saline 
efflorescence locally known as ‘“reh.” Large areas of land im- 
pregnated with this salt, or rather mixture of salts were well 
known long before the canals were constructed. It was also well 
known that if careless irrigation were allowed, the “reh” would 
spread, and every precaution was therefore taken with, it is 
believed, satisfactory results. 
