i6o 



PRINCIPLES OF STRATIGRAPHY 



Grams per liter 

 of the water 



Silica in solution (Si02) 0.065 



Sodium chloride (NaCl) 7-219 



Potassium chloride (KCl) 8 . 455 



Potassium sulphate (K2SO4) 0.921 



Potassium carbonate (K2CO3) 10 . 691 



Magnesium carbonate (MgCOs) o. 006 



Total 27 . 357 



The following analyses of the waters of Pyramid Lake, another 

 carbonate-chloride lake, show variation vertically as well as hori- 

 zontally. (Russell-30 : ^j, j8.) 



Nearly all the fresh water entering Pyramid Lake, which is 

 without outlet, is delivered at the southern end by Truckee River, 

 near the mouth of which the water is fresh enough for camp pur- 

 poses. At the northern end of the lake the water is unfit for human 

 consumption, but animals may drink it without injury. 



3. Fresh-water Lakes. Water absolutely free from mineral mat- 



* 99-23 per cent, of total solids accounted for. 

 ** 99.19 per cent, of total solids accounted for. 

 t 99-94 per cent, of total solids accounted for. 

 X Error of 0.15 per cent, in excess. 



