ROARING CAVERNS.

Hokitika Guardian, 28 September 1921, Page 2

ROARING CAVERNS.

STRANGE VENTS TO UNDERGROUND RIVERS. SYDNEY, Sept. 20. Sir Edgeworth David, Austialia s foremost geologist, who has just completed an investigation of a great artesian basin which has been discovered in an arid part of Western Australia, covering the Nallabor Hains-Euclft region, tells of some remarkable caverns of great extent which honey-comb the earth. On the surface, he says, the plain appears to he quite flat" and featureless, but when examined more closely it is found that here and there are funnel-shaped hollows which terminate often in caves of vast extent. A cave of this kind occurs about 14 miles north-west of Eucla. It can be descended to a depth of over 200 fret, the roof in places being some 40 or 50 feet high. In the lowest cave is «• large pool of crystal-clear water, which has been sounded and found to he about 35 feet deep. This water is somewhat saline, not as a result of seawater penetrating so far inland, for it is above sea. level, but because of the water containing salts dissolved out of marine limestone. The whole area is mere or less, honeycombed beneath the surface with either large caves or small er tortuous underground channels and cavities form reservoirs in some cares for water, and in all cases for large quantities of air. When any change takes place* in a barometric pressure at, the surface of the plains, remarkable things occur. If the pressure is lessen., cd owing to a fall in the barometer, air rushes out from the funnel-shaped mouths of the caves or the small openings of the wells. The air.rushes outward with a great roaring sound, the current being strong enough to blow one’s hat up into the air. When a high oresstire supervenes after a lowpressure the air current is reversed and there is a strong indraught down the wells and cave mouths. Under these vast plains the subterranean water flows at two very distinct levels.