RAINFALL AND DISCHARGE OF THE MURRAY RIVER. LIII. 
demand. Seeing that the Australian States are embarking 
on irrigation enterprises, the determination of the volume 
of water that can be depended upon should be ascertained 
with precision, so that works of diversion and storage may 
not be constructed in excess of the water that can be 
supplied. 
Losses in the Artesian Area of Queensland and New 
South Wales.—Several of the streams within the Murray 
Basin traverse the artesian area of New South Wales and 
@ueensland, andan enormous quantity of water is absorbed 
in the porous strata. In the case of artesian basins gener- 
ally, the water supply is furnished by rain and streams, and 
enters the pervious beds from above. 
According to the authority of Dr. Jack, Government 
Geologist of Queensland, in a paper read before the Aus- 
tralasian Association for the Advancement of Science, there 
is a series of soft, grey, very friable sandstone grits and 
conglomerates at the base of the lower cretaceous forma- 
tion of Queensland. This sandstone absorbs water with 
avidity. The rock is moreover so destitute of cement, or 
it may be that the cement is so soluble, that a lump of it 
on being saturated with water falls away toa heap of sand. 
This rock has been named by Mr. Jack the Blythesdale 
Braystone, and it attains its highest altitude of 1,700 feet 
above sea level at Forest Vale, on the Maranoa River. The 
outcrop is crossed by several streams in the Murray Basin, 
the principal of which are the Maranoa and Warrego Rivers. 
These streams run only for a small portion of the year, but 
while they run a rock of the bibulous nature of the Blythes- 
dale Braystone must be absorbing water greedily, and the 
water must not only spread laterally, but must also fill up 
as much of the underground portion of the stratum or strata 
as had been emptied by leakage. 
Professor David considers that two kinds of leakage 
might affect the bibulous beds at the base of the lower 
