COMPOSITION OF RU'ER WATERS 



163 



Table Shozving Total Salinity of Other Rivers. — Continued. 



Permille. 



Uruguay, above Fray Bentos o . 066 



Amazon, between the Narrows and Santarem 0.059 



Xingu, South America o. 045 



Tapajis, South America o . 038 



Amazon at Obidos o. 037 



In most of the rivers calcium is in excess, probably in the form 

 of the bicarbonate. In some cases, however, as in the Jordan River, 

 Utah, the calcium is chiefly in the form of the sulphate. 



From the analyses of the waters of twenty American rivers 

 (United States and Canada), it has been found that the average 

 total amount of solids carried in solution is 0.15044 permille, of 

 which 0.056416 permille is calcium carbonate (Russell-33 :75'). 

 Forty-eight analyses of the waters of European rivers tabulated by 

 Bischof give the average total solids in solution as 0.2127 permille 

 with an average of 0.1139 permille of CaCOg, while forty analyses 



