BY H. I. JENSEN. 525 



in excess of the amount of HC1, mass-action would assert itself 

 and lead to the precipitation Fe, Mg and Ca as carbonates, and 

 the waters would by degrees become mainly supersaturated with 

 alkali. The result would be that long before the commencement 

 of the Palaeozoic era the ocean would contain a great excess of 

 alkali over other salts, just as at present, the chemical laws of 

 solubility and mass-action ensuring this effect.- The ocean should, 

 indeed, in my opinion, have been more briny than at present, 

 having continually received immense quantities of liberated 

 magmatic water to dilute it. 



Further, Professor Joly has neglected to give due weight to the 

 importance of H 2 S0 4 as an alkali-carrier and precipitant of Ca. 

 Sulphur he neglects because it occurs in rocks only to the extent 

 of 06 %, and is carried to the ocean by rivers in sufficient 

 quantity to account for what is in the ocean. But the occurrence 

 of gypsum deposits in sedimentary rocks shows that sulphur and 

 sulphur acids have always been an important factor in the chem- 

 istry of the ocean, Sterry Hunt, rightly I think, assumed S0 3 

 to be an original component of the atmosphere. 



Sterry Hunt's view that the waters imprisoned in the old 

 sedimentary rocks are vastly richer in Ca and Mg than those of 

 modern seas, and his belief that the alkalies and alkaline earths 

 first precipitated the dissolved Fe and Al, and then decomposed 

 CaCl 2 and MgCl 2 to carbonates and formed alkaline chlorides, 

 are, as far as I can see, not at variance with geological facts, and 

 seem to be well founded, but they do not lend support to Joly's 

 theory. 



Joly also advances the hypothesis that salt deposits are formed 

 in inland seas by the evaporation of lakes, and not in isolated arms 

 of the ocean. This view is not well founded, for frequently 

 saline lake-deposits have been formed immediately after and 

 have been laid down conformably upon marine strata, so as to 

 indicate that the lake which gave rise to them was merely an 

 isolated arm of the ocean (cf. The Etage Sarmatique of the 

 Mediterranean; Suess). 



