SOILS — FERTILIZERS. 23 



Is is estimated that " the Pacific kelps can easily be made to yield upward of 

 1,000,000 tons of potassium chlorid annually, worth at least $o5,000,000, and 

 that the cost of production can largely, if not entirely, be covered by the value 

 of the iodin and other minor products. The value of the present annual im- 

 portations of potash salts from Germtiny is, in round numbers, $12,500,000." 



Potash salts: Summary for 1911, W. C. Phalen <U. 8. Geol. Hiirvey, Ad- 

 vance Chai)tcr from Mineral Resources of the United States, Calendar Year 

 1911, pp. 31). — This is an advance chapter from Mineral Resources of the 

 United States, 1911, and reports the progress in work by the U. S. Geological 

 Survey, the Bureau of Soils of this Department, and private persons in the 

 search for a domestic supply of potash, which has included investigations of 

 "(1) saline residues, (2) natural and artificial bitterns, (3) alunite and 

 similar minerals, (4) the igneous rocks containing as a lower safe limit at 

 least 6 per cent of potash (KnO), (5) the greensand marls of Kentucky, New 

 Jersey, Tennessee, and probably other States, (6) organic sources, including 

 wood ashes, beet-sugar molasses and residues, wool scourings, and seaweed." 



The work of the Geological Survey ii^ 1911 included "(1) deep drilling for 

 saline residues, (2) the collection and examination of natural and artificial 

 brines and bitterns, (3) the examinations of deposits of alunite and other 

 minerals containing potassium, (4) the examination of certain occurrences 

 of igneous rocks known to contain large quantities of potash." At the time 

 this report was made the deep drilling operations had not revealed potash 

 deposits of commercial importance; one Ohio bittern had shown a considerable 

 percentage of potash (3.9 per cent) ; a considerable deposit of rather pure 

 alunite (hydrous potassium and aluminum sulphate) had been discovered 

 near INIarysvale, Utah (E. S. R., 26, p. 526) ; and the extensive leucite deposits 

 of Sweetwater County, Wyo. (E. S. R., 26, p. 623), had been examined and 

 their potash capacity estimated at 197,349,617 short tons of potash. The ex- 

 aminations of samples of other igneous rocks, particularly those rich in potash 

 feldspar and of the pota.-^h-yieUling capacity of New Jersey, Kentucky, and Ten- 

 nessee marls had revealed little new information of special commercial im- 

 portance. Accounts are given of the fruitless search for potash salines in the 

 Otero Basin, New Mexico (see below), of methods of recovering potash from 

 alunite and other igneous rocks and marls, and of simple field and laboratory 

 tests for potash. 



Data are given regarding the consumption of potash salts in the United 

 States, amounting to 672.639,581 lbs. valued at $11,826,106 in 1911, and the 

 production of potash from wood ashes in the United States (1.866,570 lbs. 

 valuetl at $88,040 in 1910), and reference is made to the industries in which 

 potash salts are used. 



The work of the Bureau of Soils of this Department on kelp as a source of 

 potash (see abstract above) is summarized, attention being called to the recent 

 e.stablishment at Cardiff, on the coast of southern California, of a plant for the 

 manufacture of potash from kelp. 



An investigation of the Otero Basin, New Mexico, for potash salts, E. E. 

 Free (,U. S. Dept. Agr., Bur. SoiL^ Circ. 61, pp. 7). — An investigation which led 

 to entirely negative results is briefly reported in this circular. 



Potash from the Pacifi.c kelps (Jour. Indus, and Engin. Chem., 4 (1012), 

 No. 2, pp. 76, 77). — This is a brief discussion based upon the work of the Bureau 

 of Soils of this Department on the possibilities of potash production from Pacific 

 coast kelps. 



Leucite as a potash fertilizer, Z. Bonomi (R. Lab. Chim. Agr. Udine, Ric. 

 Sper. e Attiv. Spiegata, 3 (1909-10), pp. 17-25). — Comparative tests of leucite 



50696°— No. 1—12 3 



