A SURVEY OF THE FERTILIZER INDUSTRY. 29 
Potash from kelp and alunite, sugar manufacture, cement, etc. U. S. Geol. Surv., 
Press Bul. 366, p. 3-4. May, 1918. 
Potash, Domestic Production of, in 1918. U.S. Geol. Surv., Press Bul. 399, p. 1. 
February, 1919. 
Ross, W. H. The extraction of potash from silicate rocks. Soils Circ. 71.10 p. 1912. 
Ross, William H., Merz, Albert R., and Wagner, C. R. The recovery of potash as a 
by-product from the cement industry. Dept. Bul. 572. 23 p. 1917. 
Skinner, J. J., and Jackson, A. M. Alunite and kelp as potash fertilizers. Soils 
Cire. 76. 5p. 1913. 
Stockett, A. W. The potash situation, Bureau of Mines, War Minerals Investigations 
Series No. 2. 13 p. 1918. 
Turrentine, J. W. The occurrence of potassium salts in the salines of the United 
States. Soils Bul. 94. 96 p. 1913. 
Waggaman, William H. Alunite asa source of potash. Soils Circ. 70. 4p. 1912. 
Waggaman, William H. The production and fertilizer value of citric-soluble phos- 
phoric acid and potash. Dept. Bul. 143. 12p. 1914. 
Waggaman, W. H., and Cullen, J. A. The recovery of potash from alunite. Dept. 
Bul. 415. 14p. 1 fig. 1916. 
Young, G.J. Potash salts and other salines in the Great Basin region. Dept. Bul. 61. 
96 p. 8fig. 1914. 
SULPHUR. 
Smith, Philip 8. Our mineral supplies—sulphur. U.S. Geol. Surv. Bul. 666-B. 
[1917] p. 7-10. 
‘Smith, Philip 8. Sulphur, pyrite and sulphuric acid in 1916. U. S. Geol. Surv., 
Mineral resources of the United States, 1916, pt. 2:28, p. 403-432; 1917, pt. 2:4, 
p. 19-62. 
Stone, R. W. Our mineral supplies—gypsum. U. 8. Geol. Sury. Bul. 666-E. 
[1917] 3 p. 
Waggaman, William H. The production of sulphuric acid and the proposed new 
method of manufacture. Dept. Bul. 283. 39p. Ilfig. 1915. 
ADDITIONAL COPIES 
OF THIS PUBLICATION MAY BE PROCURED FROM 
THE SUPERINTENDENT OF DOCUMENTS 
GOVERNMENT PRINTING OFFICE 
WASHINGTON, D. C. 
AT 
10 CENTS PER COPY 
