1889.] NKW YORK ACADEMY OF SCIENCES. 43 



which, like that from the Ashtabula well, contain a large 

 amount of potash and bromine, and these substances may be 

 profitably extracted from tiiem. With this fact in view, it will 

 be desirable to have careful analyses made of all those brines 

 which show to the taste that they contain an abnormal quantity 

 of *' bitterns,'*' as only in such are bromine and i)Otash likely 

 to exist in paying quantities. Perhaps no such localities will 

 be found within the limits of our State, but the possibility 

 should be kept in mind. 



The unequal distribution of the '•'bitterns" in the brines and 

 salt of different localities is an interesting feature in these salt- 

 deposits. In some places almost the only ingredient of the 

 brine is chloride of sodium, and some of the rock-salt, as we 

 have seen, is almost chemically pure; in other localities, perhaps 

 not distant, the brine or the salt contains an abnormal quantity 

 of the chlorides of calcium and magnesium and the sulphate of 

 magnesia and soda. This problem has been carefully studied 

 by Prof. Chas. A. Goessmann, and he has suggested what is 

 doubtless its true solution, viz., that in the progressive evapora- 

 tion of a basin filled with water having the normal composition 

 of sea- water, the substances held in solution will be precipitated 

 in the inverse order of their solubility; — thus sulphate of lime 

 (gypsum), the least soluble ingredient, will be the first thrown 

 down, the chloride of sodium next, and lastly, if at all, the de- 

 liquescent salts which form the bitterns. If, then, a salt lake like 

 that in which the Salina group was deposited were, from the 

 evaporation of its water, constantly contracting its area, in por- 

 tions of its shallows a sheet of pure gypsum would be deposited 

 when the evaporation had brought the solution to a point where 

 gypsum could no longer be suspended. Over other portions of 

 the basin pure salt would be precipitated when the solution 

 could no longer hold chloride of sodium, and finally, as the 

 water-surface contracted, in the narrower and deeper portions of 

 the basin the bitter salts would accumulate in abnormal quantity. 



This will account for the deposition of gypsum, of pure salt, 

 and of unusually bitter salt, in different parts of the same basin. 

 Facts illustrating this distribution of the solid contents of salt 

 water are reported by Dr. Goessmann from the salt-basin of the 

 Upper Ohio, and similar facts have been brought to light in 

 boring the wells about Goderich. The salt there is of remark- 

 able purity, but in a well bored twelve miles south from Gode- 

 rich the salt was found to contain over 10 percent of '•bit- 

 terns/' 



For the better understanding of the nature and value of the 

 rock-salt deposits of western New York, a few words may be 

 said in regard to other known sources of salt in our country. 



