1865.] CHEMISTRY OF NATURAL WATERS. 179 



In the recent analyses of these waters, the carbonic acid in the 

 Gas spring was found to equal for 1,000 parts, .671 ; of which .278 

 were required for the neutral carbonates. The Saline spring con- 

 tained .664 of carbonic acid ; of which .290 go to make up the neu- 

 tral carbonates. The Sulphur spring, in like manner, gave of car- 

 bonic acid .573 ; while the neutral carbonates of the water required 

 only .191. All of these waters, in January 1865, thus contained an 

 excess of carbonic acid above that required to form bicarbonates 

 with the carbonated bases present ; while the analyses of the same 

 springs in 1847, showed, as we have seen in § 43, a quantity of car- 

 bonic acid insufficient for the formation of bicarbonates. The 

 questions of this deficiency, and of the variation in the amount of 

 carbonic acid in these and other waters, will be considered in the 

 third part of this paper. 



§ 48. The waters of our fifth and sixth classes, as defined in 

 § 34, are distinguished by the presence of sulphates ; the former 

 being acid, and the latter being neutral waters. In the fifth class 

 the principal element is sulphuric acid, associated with variable and 

 accidental amounts of sulphates of alkalies, lime, magnesia, alumina, 

 and iron. Apart from the springs of this kind which occur in re- 

 gions where volcanic agencies are evidently active, the only ones 

 hitherto studied are those of New York and western Canada; which 

 issue from unaltered, and almost horizontal Upper Silurian rocks. 

 (§ 31.) The first account of these remarkable waters was given 

 in Silliman's Journal in 1829 (vol. xv, p. 238), by the late Prof. 

 Eaton, who described two acid springs in Byron, G-enesee Co., 

 N. Y. ; one yielding a stream of distinctly acid water sufficient to 

 turn a mill-wheel, and the other affording in smaller quantities a 

 much more acid water. The latter was afterwards examined by 

 Dr. Lewis Beck (Mineralogy of New York, p. 150). He found it 

 to be colorless, transparent, and intensely acid, with a specific gravity 

 of 1.113; which corresponds to a solution holding seventeen per 

 cent of oil of vitriol. No chlorids, and only traces of lime and iron, 

 were found in this water, which was nearly pure dilute sulphuric 

 acid. Prof. Hall (Geology of New York, 4th District, p. 134) has 

 noticed, in addition to these, several other springs and wells of acid 

 water in the adjacent town of Bergen. Farther westward, in the 

 town of Alabama, is a similar water, whose analysis by Erni and 

 Craw will be found in Silliman's Journal [2] ix, 450. It contained 

 in 1000 parts about 2.5 of sulphuric acid, and 4.6 parts of sul- 

 phates, chiefly of lime, magnesia, iron, and alumina. In this, as in 



