Chemical Laboratory, University of Minnesota. 345 



ANALYSIS OF A SAMPLE OF WATER FROM '"tHE GIANT SPRING/' 



MONTANA. — /. A. Dodge. 



(i.) General characteristics: water perfectly clear, bright 

 and colorless ; odorless and palatable. 

 (2.) Mineral analysis: 



Calcium sulphate, 241. parts per million. 



Calcium carbonate, 75. " "' " 



Magnesium carbonate, 86. " " " 



(3-) 



The residue from evaporation of this water on a large watch 

 glass showed remarkable whiteness and purity. Rhombohedral 

 crystals of calcite or dolomite were visible to the unaided eye. 

 With a microscope crystals of gypsum were plainly seen, showing 

 twin and stellar forms. 



May jth, i8gi. 



ANALYSIS OF A SAMPLE OF WATER FROM AN ARTESIAN WELL AT 

 devil's lake, NORTH DAKOTA. /. A. Dodge. 



I. General characteristics : 



2. 



