Sir R. I. Murchison on the Silurian Rocks of Cornwall. 333 



which have been denuded from the surface of adjacent crystaUinc 

 rocks. With these analogies there is however a marked distinc- 

 tion between Siberia and Cornwall. All richly auriferous chains 

 (Humboldt first remarked the fact) have a meridian direction, as 

 in the Ural, and various north and south parallel ridges in Si- 

 beria and other parts of the globe. The axis of Cornwall, on the 

 contrary, is transverse to that direction, viz. from E.N.E. to 

 W.S.W. ; and though containing copper ore in common with 

 the Russian mountains, it differs from them in not producing 

 gold or platinum ; whilst it is peculiarly distinguished by con- 

 taining tin, which is unknown in the Ural. Let us hope that 

 the day is fast approaching, when the cause of the production of 

 such striking phsenomena as these will receive some explanation 

 at the hands of those physical philosophers, who are advancing 

 a line of research in which your own countryman Mr. K. W. Fox 

 has already so distinguished himself. But if gold does not exist 

 (in any appreciable quantity at least) in your otherwise richly 

 endowed mineral county, there are, I am happy to say, good 

 grounds for hope, that in their most distant great colony English- 

 men may find it abundantly. In an address to the Royal Geo- 

 graphical Society, delivered in May 1845, when commenting 

 upon the valuable labours of Count Strzelecki in deciphering the 

 structure of the great north and south chain which ranges along 

 the eastern shores of Australia, I specially insisted upon its stri- 

 king resemblances to the Ural mountains, whether in direction, 

 in structure, or in alluvia ; remarking, by the way, that as yet 

 no gold had been found in this alluvium. I now learn, however, 

 that fine specimens of gold have been found on the western flank 

 of the Australian cordillera, particularly at the settlement of 

 Batliurst, where it occurs in fragments composed of the same 

 matrix (viz. quartz rock) as in the Ural. My friend and asso- 

 ciate in the Imperial Academy of Petersburg, Colonel Helmersen, 

 has also recently suggested, that a careful search for gold ore in 

 the Australian detritus will, it is highly probable, lead to its de- 

 tection in abundance ; since the Russians had long colonized the 

 Ural mountains, and had for many years worked mines of mag- 

 netic iron and copper in solid rocks, before the neglected shingle, 

 gravel and sand, on the slopes of their hills and in their valleys, 

 were found to be auriferous. If, then, in the course of your 

 statistical inquiries, you may know of any good Cornish miner 

 about to seek his fortune in Australia, be pleased to tell him to 

 apply his knowledge of the mode of extracting tin ore from his 

 own gravel to the drift and debris on the flanks of the great 

 north and south chain of Australia*, or any smaller parallel 



* The grand, rich and well-watered region which lies between Moreton 

 Bay on the south and the Gulf of Carpentaria on the north, is that to which 



