Erosio7i in the Basin of the Arkansas River 331 



it varies inversely with the volume of the water, and ranges 

 from II to 70 grains to the U. S. gallon. This dissolved mat- 

 ter is principally chlorides of sodium, potassium, and mag- 

 nesium, and the carbonates of lime, soda, and magnesia. At 

 low stages of the river there is enough sodium chloride in the 

 water to give it a decidedly brackish taste. The analyses giv- 

 en below represent high and low stages of the water. 



ANAI^YSrS OF FILTERED ARKANSAS RIVER WATER. 



(Sample collected December 20th, 1888, when the river stood at 

 nine feet on the gage). 



Hypothetical Combination. 



Grains per Per cent, of 

 U. S. Gallon. Solids. 



Silica (SiOJ .75 11. 81 



Chloride of sodium .... (NaCl) 1.96 30-87 



Chloride of potassium . . . (KCl) .44 6.93 



Sulphate of magnesium . . (MgSOJ .14 2.20 



Sulphate of iron (FeSO^) .43 6.77 



Sulphate of alumina. . . . (Al3(SOj3) .15 2.36 



Carbonate of soda (Na^COj) 1.07 16.85 



Carbonate of magnesia . . (MgCOj) .28 4.41 



Carbonate of lime (CaCOj) 1.13 17.80 



Total, 6.35 100.00 



Found. 



Silica (SiO^) .75 11.83 



Sulphuric acid (SO.) .51 8.04 



Carbonic acid (CO:;) 1.48 23.34 



Chlorine (CI) 1.39 21.92 



Iron (Fe) .16 2.52 



Aluminum (Al) .02 .32 



Calcium (Ca) .45 7.10 



Magnesium (Mg) .11 1.73 



Potassium (K) .23 3.63 



Sodium (Na) 1.24 19.57 



Total 6.35 100.00 



