Reviews — Artesian Waters of Australia. 225 



though they are really the results of volcanic activity ") must pass 

 without discussion. Of misprints we have noticed only two ; one in 

 the letterpress of fig. 701, where 'new moon' should read 'full 

 moon' ; and the other on p. 140, where, by the dropping of a letter, 

 we get the strano-e-looking ' hills de gullies.' G. W. L. 



II. PROBLEMS OP THE ARTESIAN WaTEK SuPPLT OE AUSTRALIA, 



WITH SPECIAL eeeerence TO Professor Gregory's Theory ; being 

 the Clarke Memorial Lecture delivered before the Royal Society 

 of New South Wales, October 31st, 1907 ; by E. F. Pittmajt, 

 Government Geologist of JN^ew South "Wales. Proe. Roy. Soc. 

 N.S.W., vol. xli. 



IN the September number of the Geological Magazine for 1907 

 there was a notice of Australian geology, and incidentally the 

 subject of the Flowing Wells was dealt with, including a short 

 account of Gregory's views thereon. In the following number of the 

 Geological Magazine there appeared a letter from Dr. Malcolm 

 Maclaren, in which he strongly protested against these views on the 

 source of Australian artesian waters. Whilst concluding his letter, 

 Dr. Maclaren indicated that some of his former colleagues in Australia 

 would discuss the subject more fully. 



This has now been done by one at least of the writer's colleagues 

 in the Clarke Memorial Lecture to which attention is directed. After 

 explaining the general principles of artesian flow, more especially 

 according to American authorities, Mr. Pittman expresses his opinion 

 that the view adopted by most American geologists has much to 

 recommend it, viz., that all underground waters have their origin 

 in rainfall. The material point, then, to be argued is, "Whether the 

 artesian water supply of the Australian basin has been derived from 

 rainfall, and has been stored in the porous sandstones under hydro- 

 static or hydraulic pressure, or whether, as contended by Professor 

 Gregory, it has been evolved from underground masses of igneous 

 rocks, and is forced above the surface in bores by the influence of 

 temperature and rock-pressure." 



Surely Mr. Pittman is here somewhat overstating his case, since it 

 is doubtful if Professor Gregory maintains that the artesian supply 

 of Australia is wholly due to the above-mentioned causes. He 

 appears to admit the effect of ordinary artesian pressure in a number 

 of instances, and indeed has entered into most elaborate calculations 

 respecting the underground hydrostatic curve. The question between 

 Gregory and Pittman really is, as to whether the alternative causes 

 suggested by the former have any foundation in fact. 



After his preliminary remarks the lecturer proceeds to consider the 

 question under two heads : (1) the objections of Professor Gregory to 

 the hydrostatic pressure theory, which are discussed and answered ; 

 (2) his suggestions as to the cause of the ascent of the water in the 

 flowing wells. 



(1) The objections. These are considered seriatim, and it will be 

 sufficient to mention some of them, viz. : loss of head through friction ; 



decade v. VOL. v. — NO. \. 15 



