64 NEW YORK STATE MUSEUM 





sodium carbonate are deep-seated. The sodium carbonate might 

 in part or in whole be dissolved from the feldspars in the old 

 crystalline rocks. The carbonated waters take on calcium and 

 magnesium carbonates from the limestones encountered in their 

 upward journey, more especially from the Little Falls dolomitJ 

 They mingle with artesian waters from the west, which may furnish 

 a good portion of the motive power toward the close of the ascent. 

 Their greatest vents lie in or near the fault, which passes through 

 Saratoga Springs, but not all are demonstrably on it. The Gurn 

 spring is near a branch. The course of the fault is less clear at the 

 Geysers, at Ballston and at Round Lake, but if not the same, then 

 some other fault is probably present. For the old Albany well a 

 similar explanation is suggested. The faults furnish the upward 

 passages of the gas and dissolved mineral matter from the depths, 

 but the tight cap of slates above the limestones acts as a roof to 

 prevent their escape, except in the springs and bore holes. The 

 source of the mineral matter and the gas is probably east of Sara- 

 toga Springs and Ballston. 



