128 CHEMISTRY OF NATURAL WATERS. [IX. 



sulphates, but, on the contrary, portions of baryta and strontia. 

 Only the Sulphur Spring, which in 1847 contained the largest 

 proportion of carbonate of soda and of sulphates, still retained 

 these elements, though in diminished amounts, and was feebly 

 impregnated with sulphuretted hydrogen. If we suppose these 

 waters to arise from the commingling of saline waters of the 

 first or second class, like those of Whitby and Lanoraie, con- 

 taining earthy chlorides and salts of baryta and strontia, with 

 a water of the fourth class holding carbonate and sulphate of 

 soda, it is evident that a* sufficient quantity of the latter water 

 would decompose the earthy chlorides and precipitate the salts 

 of baryta and strontia present, while an excess would give use 

 to alkaline-saline waters containing sulphate and carbonate of 

 soda, such as were the three springs of Caledonia in 1847. 

 A falling off in the supply of the sulphated alkaline water 

 may be supposed to have taken place, and the result is seen 

 in the appearance of chloride of magnesium and of baryta and 

 strontia in two of the springs, and in a diminished proportion 

 of carbonate of soda in the Sulphur Spring.* 



These later analyses being directed chiefly to the determina- 

 tion of these changes, no attempt was made to determine potas- 

 sium, iodine, or bromine. For the purposes of comparison, 

 the two series of analyses t are here put in juxtaposition ; the 

 element just mentioned being included with the chloride of 

 sodium, and the figures reduced to three places of decimals. 

 The precipitate by a solution of gypsum from the concentrated 

 and acidulated water was regarded as sulphate of strontia, and 

 calculated as such, but was in part sulphate of baryta. 



* [The Harrowgate springs, in England, have undergone changes not un- 

 like those of Caledonia. Several of the Harrowgate waters, all of which were 

 found by Dr. Hofman, in 1854, to contain sulphate of lime, were examined by 

 Mr. Davis, in 1866, and found, with one exception, to be free from sulphate, 

 and to contain instead salts of baryta, even in the sulphuretted waters. Great 

 differences are there, as elsewhere, observed between closely adjacent springs; 

 and in one of them, a strong saline holding chloride of barium, Dr. Muspnitt 

 detected a small amount of protochloride of iron. (Chemical News, Vol XIII., 

 passim.)] 



t [The complete earlier analyses are given in the original paper.] 



