L. A. B. WADE. LXXIX. 
importance. Artesian water is rainfall which is absorbed 
on the slopes of the coastal ranges, and then finds its way 
inland under the plains by subterranean passages. The 
proved Artesian Basin is shewn on the map, and the area 
enclosed in this State is 62,000 square miles. The area of 
the upturned edges of the intake beds in the ranges has 
not yet been accurately defined, this is a matter for the 
geologists, and a proposal is now before the responsible 
Minister to have this work proceeded with as soon as 
possible. In the absence of this information it is quite 
useless to form any estimate of the quantities of artesian 
water available in the State. At the present moment, it 
does not appear that the supply is likely to fail or diminish 
seriously under the moderate demands so far made on it, 
and it cannot be lost by evaporation. It isa fact that the 
discharges of many of our bores have decreased of late 
years, but this is undoubtedly due to local causes, such as 
the silting up of the channels near the bore, or the escape 
of the water into another strata. 
The investigations which are being carried out are to 
afford an accurate record of the flow at different levels 
above the surface. In other words the hydraulic grade of 
the underground flow is to be determined. Some of the 
existing bores fluctuate from day to day, and it is also pro- 
posed to make observations on these over extended periods. 
The direction of the underground flow can be plotted by 
determinining the lines of equal hydraulic pressure, and the 
completion of this work will settle the vexed question of 
the outfall into the ocean. The pressures of each bore 
will be taken by means of a gauge, and the flow will be 
estimated by passing it over a weir or notch. 
In addition to the artesian supply there are sub-soil 
supplies all over the State. It is highly propable that these 
are fed by percolation from the rivers, and as the depth 
