132 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 4, 



also detected. There was evidence also of the schists having under- 

 gone various transmuting influences, and of the granites having suf- 

 fered from causes which had in places produced disintegration. The 

 Carboniferous formation was exhibited as resting upon the older rocks, 

 either reposmg unconformably upon the tilted schists or granites, or 

 passing into the ancient conglomerates derived from the latter*. I 

 discovered at that time the presence of gold, both in quartzites, and 

 in the detrital accumulations derived from the axial formations ; but 

 it was only sufficient to enable me to declare that gold existed within 

 eighty and sixty miles of Sydney. 



By subsequent researches, the author's acquaintance with the geo- 

 logy of the country was considerably extended, and he was led to 

 regard Australia as an auriferous region of considerable promise, — an 

 opinion which he has promulgated in several of the local journals ; 

 and ultimately he was convinced (as expressed in a letter, a quotation 

 from which appeared in the * Quarterly Review' for September 1850) 

 that copper, lead, and gold are to be found in considerable abundance 

 in the schists and quartzites of the Cordillera (Blue Mountains). 

 Under these terms are included all the alternations of the schistose 

 formation which occur between 27° and 38° lat. ; that portion, how- 

 ever, being chiefly alluded to that lies between the Liverpool Range 

 and Wilson's Promontory. Having had ocular proof that gold ac- 

 tually existed in many places within an area represented by 9° of la- 

 titude and 4° of longitude, the author felt justified in extending his 

 assertion with respect to the presence of gold in Australia, so as to 

 embrace the further extent of country throughout which rocks of a 

 similar kind extend. After dwelling on the similarity of the geo- 

 gnostical characters of the Australian and the Ural Ranges, — his views 

 on which were published in 1847tj — and on the meridional parallel- 

 ism, at the respective distances of exactly 90°, that obtains apparently 

 amongst what he considers to be the several great auriferous moun- 

 tain-ranges of the world, Mr. Clarke proceeds to observe, that the 

 most recent intelligences enable him to state that the actual length 

 of the auriferous quartz ranges is full sixty miles, if not more, reckon- 

 ing from Summer Hill, which is the range separating the waters of the 

 Bolubula, an affluent of the Lachlan, from the basin of the Macqua- 

 rie, in which the gold-diggers are now employed. Summer Hill is not 

 more than ten miles east of the summit of the Canobolas, a cluster of 

 basaltic and porphyritic hills, which have burst through the schists, 

 and have transmuted also the overlying fossiliferous limestones. 

 Taking the width of the auriferous region in this part of the basin of 

 the Macquarie at twelve miles, we have here an area of at least 720 



* For an account of the Palaeozoic Rocks of New South Wales, see Quart. Journ. 

 Geol. Soc. vol. iii. p. 241 et seq., and vol. iv. p. 60 et seq. Also Strzelecki's Phy- 

 sical Description of N. S. Wales and Van Diemen's Land, p. 87 etseq., and Jukes' 

 Physical Structure of Australia, p. 11, and p. 18 et seq. 



f A comparison of the phsenomena of the Ural with those of Australia (which 

 Mr. Clarke was enabled to institute by means of an Abstract of M. de Verneuil's 

 Report to the Geological Society of France, on the Researches in Russia by Sir R. I. 

 Murchison, Count A. Keyserling, and himself) was published in the Sydney Herald, 

 Sept. 28, 1847. 



