UTILISING WASTE UNDERGROUND WATER. ' 571 



-data, and froin levels taken with the Aneroid barometer, I laid 

 down last year a hydrogeological section of the country from tlie 

 Coouatto Range, past the township of Bruce, across tlie Willochra 

 Valley and the Flinders Range referred to, as far as the next 

 valley of the Capowie Creek. On this section I showed the line 

 of surface, and underneath, and nearly parallel to it, the line of 

 saturation or underground waterline on the slope of the hills, and 

 projected this latter line under the plain at the tow^nship of Bruce 

 at a depth of one hundred and ninety feet, 1 notice whilst writing 

 • that a boring party, under the Conservator of Water (Mr. J. 

 W. Jones), have just struck Avater near Bruce at about that 

 depth, which is artesian, and, rising to the surface, flows over at 

 the I'ate of 10,000 gallons per day. 



The conclusion I am inclined to draw from these and other data 

 are the following, namely : — 



1. The underground waters of that district, coming from the 

 hills, are flowing below in the same general direction as the fall 

 on the surface of the country, and on a line nearly parallel to it. 



The general course of the underground water on one side of the 

 Willochra Creek basin is shown in a section which I have pre- 

 pared ; it is most probable that the same conditions prevail 

 generally throughout the Flinders Range, of which this is a part. 

 The underground witters from the Mount Lofty Range seem also 

 to pass under the plain in a similar position. 



2. The sources of these underground waters is percolation from 

 the surface. This percolation takes place chiefly under the beds 

 of rivers and creeks, and other water courses in the hills and on 

 the plains, in a vertical direction, and also latei'ally on each side 

 of the stream. 



In South Australia that portion of the rainfall is much the 

 larger which never reaches the rivers and creeks, but enters the 

 ground on or near the spot v.diere it falls, and goes to swell the 

 volume of subterranean streams. Tliis proportion varies much 

 in different countries. In England the rainfall is sometimes 

 roughly divided as follows, viz. : — One-third for evaporation and 

 absorption ; one-third for percolation into the ground to form 

 springs ; and, the remaining one-third drained into the rivers. In 

 warmer and drier climates the proportions for percolation and 

 absorption ai-e very much greater. On the Buflalo River, Africa, 

 four-flfths of the rainfall is lost by evaporation and pei'colation 

 underground. In most countries gaugings of the flow of water in 

 the various streams have been taken during a course of years and 

 those compared with the rainfall records, so that in any particular 

 district the available quantity of water that can be conserved may 

 be estimated with sutiicient accuracy ; in this colony we have only 

 very slight data of this kind ; rainfall guagings have been taken 

 for several years, but for practical purposes they are of very little 



