CHEMISTRY OF NATURAL WATERS. 



177 



To illustrate still further the complex character of the mineral matter 

 impregnating spring waters, and at the same time to indicate the changes in 

 composition to which springs are subject, we give below two analyses of 

 the waters of the same spring collected at different seasons. The sample 

 obtained in October was secured after a rain that followed a long dry pe- 

 riod, and probably owes its greater richness to saline efflorescences accu- 

 mulated in the intei'stices of the rocks during the arid season and redissolved 

 by the percolating rain water : 



Bockbridge Alum Spring No. 4, Eockbridge County, Virginia.^ Analyses by I'rof. M. B. Hardin. 

 [Keported in grains of nnbydroas coDstituents in one U. S. gallon.] 



Conetitaents. 



Arsenic 



Antimony 



Lead sulphate 



Copi)er sulphate 



Iron persulphate 



Iron protosulpbate . . . 

 Man!,'ane8e sulphate.. 



Nickel sulphate 



Colbalt sulphate 



Zinc sulphate 



Aluminum sulphate .. 



Calcium sulphate 



Maj^nesium sulphate . 

 Potassium sulphate. . . 



Sodium sulphate 



Lithium sulphate 



Free sulphuric acid . . . 



Silicic acid 



Sodituu chloride 



Calcium jihosphate ... 



Calcium fluoride 



Ammonium nitrate ... 

 Organic matter 



Specific gravity at 60° Fahr 



Cubic inches of gases in gallon of water : 



Carbon dioxide 



Oxygen -' — 



Nitrogen 



Collected 

 June 9, 1872. 



Collected 

 October 25, 1872. 



0.00161 

 trace. 

 0. 87962 

 0. 51527 

 0. 05433 

 0. 03835 

 0. 05225 

 18. 99905 



0. 35228 



1. 50165 

 0. 06278 

 0. 00876 



0. 01790 



2. 53866 



1. 92591 

 0. 14246 



trace, 

 trace, 

 trace, 

 trace. 



27. 09088 



not determined, 

 not determined. 

 not determined. 



trace. 



trace. 



trace. 

 0. 10370 

 2. 90122 



1. 37352 

 0. 22371 

 0. 08124 

 0. 21748 



72. .37335 



2. 31527 

 7. 36110 

 0. 17586 

 0. U3463 

 0. 03241 



3. 06633 



4. 38346 

 0. 14246 

 0. 05174 



trace, 

 trace, 

 trace. 



94. 83748 

 1. 00174 



12.72 

 1.64 

 4.12 



Temperature of spring 54.5*^ Fahi. 



Springs of even more complex composition than the example given 

 above might be presented if desired ; in fact, subterranean waters are so 



MoN. XI— 12 



"Americau Chemist, 1884, p. 247. 



