Journal and proceedings of the Royal Society of New South Wales . f the central artesian basin, the water mustbe stagnant. It is difficult to understand why the Professor arrives atthis conclusion. The water must circulate through thelowest parts of the basin, so long as it has sufficient head. x Ibid., p. 299. PROBLEMS OF THE ARTESIAN WATER SUPPLY OF AUSTRALIA. 127 The fact that that part of the basin beneath Lake Eyre isfar beloiv the level of the outlet into the Gulf of Car-pentaria is of no consequence so long as the source ofthe water, or in other words the outcrop of the porous beds,is a
Journal and proceedings of the Royal Society of New South Wales . f the central artesian basin, the water mustbe stagnant. It is difficult to understand why the Professor arrives atthis conclusion. The water must circulate through thelowest parts of the basin, so long as it has sufficient head. x Ibid., p. 299. PROBLEMS OF THE ARTESIAN WATER SUPPLY OF AUSTRALIA. 127 The fact that that part of the basin beneath Lake Eyre isfar beloiv the level of the outlet into the Gulf of Car-pentaria is of no consequence so long as the source ofthe water, or in other words the outcrop of the porous beds,is at a sufficient altitude above the submerged granite barrierat Manfred Downs. If Gregory had continued his sectionfrom Charleville on to Toowoomba, as lias been done in thesketch (Plate VIII), the fact that the porous beds therehave an outcrop at least 1,000 feet higher than Charlevillewould have been apparent. It may be added that the waterbeneath Lake Eyre is not stagnant for the same reasonthat the water at E, in figure 1, (which is reproduced from p . , . p*. 44 The Dead Heart of Australia) would not be stagnant,but would flow over the barrier at F, so long as its sourceis at a higher level. An inspection of the country between Brisbane andToowoomba would probably convince Professor Gregorythat the artesian basin has no outlet in the neighbourhoodof the first named place. It will be seen in the section(Plate VIII), that Toowoomba lies at an elevation of about2,000 feet above sea-level, that the Triassic sandstoneshere have a westerly dip, and that immediately east ofToowoomba there is a steep escarpment leading down tothe coastal plain on which Brisbane is situated. A con-siderable outcrop of palaeozoic rocks (regarded by Dr. Jackas Lower Carboniferous) occurs near Brisbane, and it ismore than possible that an area of Permo-Carboniferoussediments may underlie the Triassic sandstones near themountains. A bore at Laidley, 51 miles west of Brisbane, 128 E. F. PITTMAN. yielded a
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