174 



A. Hague — Deposition of Scorodite, etc. 



Constant Geyser. 



Old Faithful Geyser. 



Grams per 



Pe 



r cent of to- 



Grams per 



Per ceot of to- 



kilogram 



tal 



material in 



kilogram 



tal material in 



of water. 



so] 



ution. 



of water. 



solution. 



Silica 0-4685 





28-88 



0-3828 



27 52 



Sulph. acid ... 0-0923 





5-69 



0-0152 



1-09 



Carbonic acid.0'0155 





•95 



0-0894 



6-43 



Boracic acid. .0-03 17 





1-95 



0-0148 



l-ov 



Arseniousacid 0*0018 





•11 



0-0021 



•15 



Chlorine 0-5740 





35-39 



0-4391 



31-57 



Bromine trace 





_ 



0-0034 



•25 



Hydr. sulph... none 





. . . . 



0-0002 



•01 



Oxygen (basic)0-0185 





1-14 



0-0419 



3-02 



Iron . . trace 





_ 



trace 







Aluminium ...0-0048 





•29 



0-0009 



•06 



Calcium 0-0146 





•90 



0-0015 



•11 



Magnesium ...0-0018 





•11 



0-0006 



•04 



Potassium 0-0745 





4-60 



0-0267 



1-92 



Sodium 0-3190 





19-67 



0-3666 



26-36 



Lithium 0-0030 





•19 



0-0056 



•40 



Ammonium 0-00127 





•08 



o-ooooi 





Hydr. (HC1). .0-0008 





•05 



. 



_ _ 



Manganese 





... . . 



trace 



. . 



Calcium . 









trace 





Rubidium 









trace 







Total ..1-62207 100-00 



Albuminoid ammonia, none 



1-39081 



100-00 

 0-00002 



Thermal waters from the Upper, Lower and Norris Geyser 

 Basins do not differ essentially in their ultimate mineral con- 

 stituents but show considerable variation in the relative 

 amounts of the salts present. All the waters from the geysers 

 which have been subjected to chemical analysis carry arsenic, 

 the quantity present, according to G-ooch and Whitfield, vary- 

 ing from -02 to -25 per cent of the mineral matter in solution. 

 That the arsenic of the scorodite is derived from the thermal 

 waters is beyond question, and in my opinion, it is supplied to 

 the waters by the action of superheated steam upon the rhyo- 

 lite lavas which form the great mass of volcanic rocks of the 

 Park plateau. 



"While arsenic has been determined in nearly all these waters 

 in no instance has the presence of even a trace of deleterious 

 metal been detected. Arsenical waters of sufficient strength 

 and suitable for medicinal purposes are of rare occurrence. In 

 the United States an undetermined trace of arsenic is reported 

 in the Orkney, Eockbridge Alum, and Roanoke Red Sulphur 

 Springs in Virginia,* and Dr. A. C. Peale informs me that so- 



* Mineral Springs in the United States; Dr. A. C. Peale. Bull. 32, U. S. Gepl. 

 Surv., p. 64. 



