28 BULLETIN 798, V. S. DEPARTMENT OE AGRICULTUEll. 



MANURE. 



Beal, W. H. Barnyard manure. Farmers' Bui. 192. 32 p. 1904. 



Brodie, D. A. Handling barnyard manure in eastern Pennsylvania. Farmers' Bui. 



978. 24 p. 4 fig. 1918 

 White, H. C. Barnyard manure. Farmers' Bui. 192. 16 p. 1897. 



PEAT. 



Turp, James S. Peat in 1915. U. S. Geol. Surv., Mineral resources of the United 

 States, 1915, pt. 2:34. 4 p. 



PHOSPHORUS. 



Stone, Ralph W. Phosphate rock in 1917 with notes on phosphorus, U. S. Geol. 



Surv., Mineral resources of the United States, 1917, pt. 2:3, p. 7-18. 

 Stone, R. W. Our mineral supplies — phosphate rock. U. S. Geol. Surv. Bui. 



66&-J. [1917] 4 p. 

 Waggaman, W. H., and Wagner, C. R. Analysis of experimental work with ground 



raw rock phosphate as a fertilizer. Dept. Bui. 699. 119 p. 1918. 

 Waggaman, William H. The manufacture of acid phosphate. Dept. Bui. 144. 28 p., 



5 pi. 1914. 

 Waggaman, William H., and Fry, WilUam H. Phosphate rock and methods proposed 



for its utilization as a fertifizer. Dept. Bui. 312. 37 p. 1915. 

 Waggaman, William H. Phosphate rock our greatest fertilizer asset. Yearbook 



1917, p. 177-183. Sep. 730. 

 Waggaman, William H. The production and fertilizer value of citric-soluble phos- 

 phoric acid and potash, Dept, Bui, 143. 12 p. 1914. 

 Waggaman, William H. A report of the natural phosphates of Tennessee, Kentucky, 



and Arkansas. Soils Bui. 81. 36 p. 4 pi. 1912. 

 Waggaman, William H. Report on phosphate fields of South Carolina. Dept. Bui. 



18. 12 p., 3 pi., 1 fig. 1914. 

 Waggaman, W, H. Review of phosphate fields of Florida. Soils Bui, 76. 23 p, 1911, 

 Waggaman, W, H, A review of phosphate fields of Idaho, Utah and Wyoming. 



Soils Bui, 69. 48 p. 1910. 

 Waggaman, William H. The utilization of acid and basic slags in the manufacture 



of fertilizer. Soils Bui. 95. 18 p, 1913, 



POTASH. 



Brown, Frederick W, Importance of developing our natural resources of potash. 



Yearbook 1916, p. 301-310. 3 fig, Sep, 717. 

 Cameron, Frank K, Possible sources of potash in United States, Yearbook 1912, 



p, 523-536. Sep. 611. 

 Cameron, Frank K. Potash from kelp. U. S. Dept. Agr. Rpt. 100. 122 p., xl pi. 



- 1915. Atlas of 69 maps 1914. 

 Cushman, Allerton S. The use of feldapathic rocks as fertilizers. Plant Industry 



Bui. 104. 32 p. 1907. 

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



Circ. 61. 7 p. 1912. 

 Gale, Hoyt S. Our mineral supplies— potash. U. S. Geol, Surv. Bui. 666-N [1917] 



4 p. 

 Mid-year statistics on production of potash. U, S, Geol, Surv., Press Bui. 379, p, 4. 



Sept, 1918. 

 Phalen, W. C. Potash salts 1915 with bibliography by W. C. Phalen, with simple 



tests for potash by W. B. Hicks. U. S. Geol. Surv., Mineral resources of the 



United States, 1915, pt. 2, p. 95-133. 



