EXAMINATION OF WATERS OF GREAT SALT LAKE. 247 



From the foregoing table it will be observed that the sea water and 

 Salt Lake water do not differ so greatly in the relative amounts of their 

 solid constituents as is generally supposed. Both are characterized by 

 the great preponderance of common salt. The principal difference is 

 in the character of the sulphates — magnesium and calcium sulphates 

 l)redominating in sea water, and sodium sulphate being pn-sent in 

 Salt Lake water. It will be noticed that sodium sulphate is not 

 regarded as a probable constituent of Salt Lake water by Waller, 

 although it is a well-known fact that during cold weather it is thrown 

 on the shores in quantities available for economic purposes. Sodium 

 carbonate and sodium bicarbonate, the "soda" which produces the 

 alkalinity of many of the lakes of the arid regiou, are absent in the 

 waters of both the sea and Great Salt Lake. From an inspection of 

 the analyses there appears to be no warrant for the objection that the 

 divergent composition of marine and Salt Lake waters would render 

 the latter ill adapted or inimical to animals accustomed to life in the 

 former, i)rovided that the same density holds in each case. As has 

 been already mentioned, it was found by laboratory experiment that 

 marine diatoms would flourish in pro[)erly diluted Salt Lake water. 



A partial experiment with fishes was made with a small quantity of 

 Salt Lake water shipped to Washington through the kindness of a 

 correspondent. The ({uantity was too small for^a conclusive trial, but 

 so far as it went the result was unfavorable, the fish showing distress 

 after a short stay in the water, and dying within two days of the time 

 of their introduction. The density of Salt Lake water was reduced to 

 the same degree (1.016) as the salt water in the aquaria in which the 

 fish had been living, so as to minimize the shock resulting from the 

 transfer from one jar to the other. 



The salts in Great Salt Lake are derived from the fresh-water streams 

 and from the fresh and brackish springs flowing into it or discharging 

 in its bottom. The proportion of saline matter in most of the streams 

 is low, although in excess of that usually found in more humid regions, 

 but many springs rising near the rim of the lake are more heavily 

 charged with salts. Some of these have been already discussed and the 

 amount of their salinity indicated, but others of thermal character are 

 much more saline. It is stated that all of the springs arising in the 

 Bonneville beds are brackish. As the lake is without an outlet and 

 all of its surplus water is removed by evaporation, the salts accumu- 

 late, and by a process of concentration the waters have reached the 

 condition of a brine. Certain salts of limited solubility and abundant 

 supply have reached the saturation stage and are being precipitated, 

 while others less abundant in the surrounding formations, or more 

 soluble, are still accumulating. The determination of the i)eriod of 

 accumulation of salts now in the lake is a complex one, "but we can 

 safely say that the j^eriod necessary to charge the lake with common 

 salt by means of the present sources and rate of supplj- is not more 

 than 25,000 years."* 



'Gilbert, Grove Karl. Lake Bonneville. U. S. Geol. Survey. Monograph I, 1890. 



