156 



PRINCIPLES OF STRATIGRAPHY 



Permille. 



1869 149 94 li 



1877 137-90 I* 



1879 156.71 li 



Permille. 



?5 167.16 



^9 19558 



)2 230.36 



Elton Lake, Russia, gave in April a salinity of 255.6 permille; 

 in August 264.980 permille, and in October 291.300 permille, the 

 specific gravity in the last case being 1.273. 



The vertical range in salinity is well shown by a number of 

 analyses of the waters of the Dead Sea, which are here tabulated. 

 (Terreild, in Clarke, 4.) 



Tabic Shoiving Vertical Range in Salinity in the Dead Sea. 



The salinity of the River Jordan, flowing into the Dead Sea, is 

 only 1. 61 permille. Its carbonates and gypsum are precipitated 

 when it enters the lake, and its contribution consists almost entirely 

 of chlorides, derived from the Cretacic salt- and gypsum-bearing 

 strata of the region. Soda Lake, Nevada, at one foot below the sur- 

 face, where the specific gravity was i.ioi, gave a salinity of 113.644 

 permille. a large part being carbonate and sulphate of sodium. At a 

 depth of 100 feet the salinity was 1 13.651 permille. 



The waters of salt and alkaline lakes may be divided into several 

 fairly well-defined groups (Clarke-4 : Jj-^-ij^*). Among the salt 

 lakes we have first a group of normal chloride waters, characterized 

 mainly by sodium chloride, and having a close resemblance to 

 oceanic water. They may represent remnants of the ocean water, 

 or the salts may be due to leaching of ancient marine deposits carry- 

 ing oceanic salt. The analyses of the waters of Great Salt Lake 

 (A^) and of Illyes Lake, Hungary (Ao) may be taken as examples. 

 The second group is that of Natural Bitterns derived from the pre- 



