174 



THE SALTON SEA. 



on the composition of disappearing lake waters and on the deposition of calcium and other 

 substances from these waters. The reduction of sulphates in the lake water by Spirillum 

 and other forms resulted in the formation of hydrogen sulphide as one product, some of 

 which would escape into the air, while a portion would be oxidized by Beggiatoa, with the 

 separation of free sulphur and the hberation of sulphuric acid. Oxides of iron might also 

 be formed and all of the above recombinations might take place in stages of concentration 

 in which no such action would occur in biologically sterile solutions. The intervention 

 of algal and bacterial organisms in the formation of a type of travertine characteristic of 

 the higher levels of Blake Sea has also been demonstrated beyond reasonable doubt. 

 These processes seem to be carried on much more vigorously in the presence of organic 

 matter, and the results of such activities are particularly in evidence in the vicinity of 

 decaying stems and woody structiu-es of all kinds. Furthermore, the hydrolyzing action 

 of organisms of the Amylobacter group upon the cortical tissues of the plants submerged 

 by the waters of the lake is a matter of some interest in the study of the formation of coal 

 deposits and in the making and preservation of fossils. 



The Cahuilla Basin is subject to a mixed type of climate. It lies far enough inland so 

 that overheating should result in a continental type of climate, particularly with respect 

 to the rainfall. Its great bowl, however, hes immediately in the lee of a great mountain 

 range which rises abruptly from its southwestern side, with the result that fringes of moun- 

 tain storms reach out over part of its area at times, while the topographical conditions 

 favor the development of the intense and localized precipitation known as cloudbursts. 

 The general features of the precipitation are shown in table 35, furnished by the U. S. 

 Weather Bureau. 



