518 EXPERIMENT STATION EECOED. 



is also thought that the results support the theory that the benefit sometimes 

 produced by potash fertilizers when applied to soils very deficient in decaying 

 organic matter may be due in part to the power of the soluble potash salt to 

 increase the availability of phosphorus and other elements. 



Salines in the Owens, Searles, and Panamint basins, southeastern Cali- 

 fornia, H. S. Gale {U. 8. Geol. Survey Bui. 580-L {WW, PP. VI+251-323, pis. 

 3, figs. 31; al)S. in Amer. Pert., 42 {1915), No. 8, pp. 42-51, figs. S).— This is a 

 preliminary report summarizing the history of the saline deposits of these 

 basins, which are believed to have been produced by the concentration and ulti- 

 mate disappearance of "waters that formerly filled Owens Valley until they 

 overflowed, flooding successively lower and lower basins, and forming for a time a 

 chain of large lakes in what is now the desert region of southeastern California." 

 " These flood waters passed from Owens Valley, the principal source of the water 

 supply, through Indian Wells, Searles, and Panamint valleys, in each of which 

 there was an extensive lake. Finally the waters are believed to have over- 

 flowed also into Death Valley. ... It is the purpose to point out in the present 

 paper the more salient distinguishing features and relations of these several 

 basins and to suggest interpretations that may be placed on their influence in 

 saline deposition." 



It is estimated that the Searles Lake deposit contains 4,000,000 tons of water- 

 soluble potash salts. In six analyses of brine from Searles Lake reported in 

 this bulletin, the potassium varied from 5.54 to 7.27 per cent. Searles Lake 

 is thought to offer the most promising prospect of commercial production of any 

 of the localities so far examined for potash deposits. The author is of the 

 opinion, however, " that commercially valuable concentrations of potash are not 

 to be looked for in the desert-basin deposits generally. In the first place, salines 

 deposited by shallow, intermittent lakes are not only so mixed with muds as to 

 render their profitable recovery very doubtful, but such deposits are unlikely 

 to retain on a large scale any considerable percentages of potassium in the solu- 

 ble form. Only in the basins where large and deep saline lakes have existed 

 and dried up under favorable conditions are massive deposits of saline free 

 from mixture with mud to be looked for. Such conditions are rather excep- 

 tional. Probably few desert saline lakes have in fact dried up so free from the 

 mixture of clay or other sediments that their water-soluble salts have retained 

 the major portion of the potash originally present in the lake water. 



" The confident hope is still held out that these exceptional conditions exist 

 in some places and that by good fortune or otherwise they may be revealed. 

 It seems that in Searles Lake one such exceptional place has been found, and 

 it is possible that there may be even larger and more valuable deposits still to 

 be discovered." 



German potash situation, J. G. Lay {U. 8. Dept. Com., Com. Rpts., No. 76 

 {1915), p. 10). — The authorized deliveries of potash for domestic and foreign 

 consumption during 1915 are given. These amount to 948,800 metric tons of 

 potash (KaO) as compared with 1,166,600 metric tons for 1914. It is "stated 

 that plans for denaturing potash salts so that the embargo can be removed 

 have not yet materialized and the embargo, therefore, still remains in force. 



The phosphate deposits of South Carolina, G. S. Rogers {TJ. 8. Oeol. Sur- 

 vey Bui. 580-^ {1914), pp. 183-220, pi. 1, figs. 2; ahs. in Amer. Pert., 42 {1915), 

 No. 2, pp. 37-49, fig. 1). — The history, character, distribution, amount available, 

 methods of mining, present status, and future prospects of these phosphates are 

 discussed. 



It is showTi that production has fallen off greatly within the last few years. 

 In 1912 it was only 131,490 tons, or about that of the period between 1875 and. 

 ISSO. While the prospects of a marked revival of mining operations in this 



