304 ON THE TRANSMUTATION OF ROCKS, &c., 



We must now look a little closer to the condition of these 

 transmuted sandstones. 



I have mentioned under the head of granitic rocks the 

 alterations near the Sappa Bulgas, and the extension of a line of 

 transmuted sandstones along the Darling, Narran, and so on into 

 Queensland. I am now able to state that, from information 

 obtained in October last, from the journal of Mr. Arthur Bloxam, 

 and from Mr. M'Hattie more recently, that these altered sand- 

 stones extend as far as Paroo River and beyond, and it is 

 remarkable that at a very short distance from them exists a 

 development of basalt, leaving us in no doubt that that rock 

 has had something to do, as well as granite, with the transmuta- 

 tions to the westward. The locality reached by Mr. Bloxam 

 was about 29 S., and between 144 and 145 E., or 130 miles 

 to the N.N.W. of Oxley's Table Land. He mentions in one part 

 of that country a sudden chasm, implying depression of a portion 

 of a sandstone country, and the occurrence of springs similar to 

 those which appear to rise along the line of transmuted country, 

 from the Warrego to the north of South Australia. 



The transmutation must have been very considerable also in 

 the Peak Downs and Mackenzie River districts, for, about 23 S., 

 and 148 E., many of the creeks are filled with altered sandstones 

 and shales like those already described. 



A similar remark may be made respecting portions of country 

 in ]ST.W. Australia. 



The sandstones of the Glenelg River, and of Brecknock and 

 Camden Harbours, and in patches all through Tasman's Land 

 and De Witt's Land, are in similar condition, as the specimens 

 before us prove. 



Mr. F. T. Gregory found semi-columnar sandstone in con. 

 junction with trap on the Sherlock River, in 21 29' 10" S., and 

 118 42' E. Springs were common in that region. 



The connection of springs with transmuted rocks and lines of 

 fissure is beautifully illustrated in a recent paper in the " Comptes 

 Rendus," by Messrs. Martin and Garrigou, under the head of 

 " Physique du Globe" on the mineral springs of Ax and Luchon. 

 The authors show how granites have been changed and formed also 

 out of neighbouring materials, where springs have traversed the 

 rocks. 



