C PROCEEDINGS OE THE GEOLOGICAL SOCIETY. [May I909, 



signs of coming to an end. 1 These stocks may be regarded as 

 having been an important source of sodium-chloride. 



Hot springs are probably only one of the superficial mani- 

 festations of the deep-seated juvenile waters. They may possibly 

 infect the shallower or ' vadose ' circulation with various kinds 

 of mineral matter, including sodium-chloride. 



Juvenile waters discharge directly into some of the tributaries 

 of the Mississippi — the hot springs of the Yellowstone Park for 

 instance, some of them, like Old Faithful, containing 367 parts 

 of sodium per million and 439 parts of chlorine. 



Prof. Suess 2 has assigned an even greater importance to juvenile 

 waters. They are emitted, according to him, as exhalations from 

 the heated interior of the earth, and furnish fresh supplies of 

 saline water to the Ocean, which has thus been maintained in a 

 state of continuous growth from the very earliest times down to 

 the present day. 



The quantity of sodium-chloride supplied by this means to 

 the Ocean may be great, but unfortunately we have no means of 

 estimating it. On the other hand, ancient deposits are certainly 

 the source of a large proportion of the salt met with in existing 

 rivers ; and the practical question which presses for solution is 

 as to what extent, if at all, this should be reckoned as an asset 

 in calculating the annual supply of fresh sodium to the Ocean. 



If the sodium of these deposits is of marine origin, it must 

 certainly be excluded. If it is the product of an ancient system 

 of inland drainage, it might fairly be taken into account, provided 

 we could be sure that it was being supplied at an appropriate 

 rate ; but we have no criterion by which to judge what this rate 

 should be. If we could base our calculation on statistics relating 

 to the total freshwater drainage of the world, this difficulty would 

 probably disappear ; for, if at certain localities the rate of supply 

 were above the normal, at others it would be below, and on the 

 whole irregularities would cancel out. The region with which we 

 have to deal is hardly large enough for this ; but attention may 

 be called to the Great Inland Basin of North America, which is 

 cut off from all apparent communication with the Ocean, and 

 thus intercepts a large amount of sodium. This is not sufficient, 



1 J. H. Collins, Quart. Journ. Geol. Soc. vol. lxv (1909) p. 155. 



2 Eduard Suess, 'Ueber Heisse Quellen' Verbandl. Gesellscb. Deutscber 

 Naturforscber & ./Erzte, 1902, Allgem. Tbeil. 



