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contemporaneous disintegration ; it may perhaps fairly be included 

 in our estimates, but not until we have enquired further into its 

 origin. As a first step, we may refer it to the waters of an 

 ancient salt-lake now dried up. But it is not so easy to account 

 for the origin of the salt in such a lake. In some cases, as in the 

 massive deposits of Stassfurt, the arguments in favour of a marine 

 origin seem conclusive. In other cases, as in the Trias of our own 

 islands, we are accustomed to look to the waters of the inland 

 drainage as the source. If this view be correct, as the facts seem 

 to indicate, then the ultimate origin of the salt still remains to be 

 discovered. 



May we suppose that it is to be found in what Posepny terms 

 ' juvenile ' water ? 



The rise of the Armorican mountains was accompanied, in the 

 South-West of England, by the intrusion of great granitic masses : 

 whether these actually gave rise to volcanic phenomena at the 

 surface need not be discussed in this connexion ; but that hot 

 springs were fed by them with mineral matter appears to be 

 certain. The roots of such springs, now exposed by denudation 

 as metalliferous lodes, seam the ancient rocks of Cornwall and 

 Devon. Saline solutions still circulate in these lodes, as in 

 the case of Huel Clifford, near Camborne, where hot water 

 (125° P.) was encountered at a depth of 1320 feet below sea- 

 level, issuing at a rate of 150 gallons per minute, and charged 

 with salts, chiefly chlorides, to the extent of about 9000 parts 

 in one million. Similarly, at Huel Seton, in the same neighbour- 

 hood, a stream was met with at a depth of 780 feet, which was 

 found to contain chlorides to the extent of 14,000 parts per 

 million. 1 



During the epoch of the Trias, when these numerous lodes were 

 overflowing with saline solutions, they may have afforded large 

 supplies of sodium-chloride to the contemporary inland seas. The 

 presence of copper-ores and rare vanadium-minerals in the New 

 Red marls is suggestive in this connexion. 



There is increasing evidence to show that the great kaolin- 

 stocks of Cornwall and Devon were produced by the action of 

 waters charged with chlorine ascending from below. They are 

 not the result of atmospheric weathering. However deeply down 

 they have been followed by excavations, they have never given 



1 J.A.Phillips & H.Louis, 'A Treatise on Ore-Deposits' London, 1896, 

 pp. 201-202. 



