286 SOILS AND FERTILIZERS 



56. Beal : U. S. Department of Agriculture, Farmers' Bulletin 

 No. 21. 



57. Minnesota Agricultural Experiment Station, Bulletin No. 26. 



58. Mainly from Armsby : Pennsylvania Agricultural Experi- 

 ment Station, Report 1890. Figures for grains calculated from 

 original data. 



59. Heiden : Dungelehre. 



60. Liebig : Natural Laws of Husbandry. 



61. Cornell University Agricultural Experiment Station, Bulle- 

 tins Nos. 13, 27 and 56. 



62. Kinnard : From Manures and Manuring by Aikman. 



63. Wyatt : Phosphates of America. 



64. Wiley : Agricultural Analysis, Vol. III. 



65. Goessmann : Massachusetts Agricultural Experiment Station, 

 Report i8Q4. 



66. Connecticut (State) Agricultural Experiment Station, Bulle- 

 tin No. 103. 



67. Goessmann: Massachusetts Agricultural Experiment Station, 

 Report 1896. 



68. Wheeler : Rhode Island Agricultural Experiment Station, 

 Reports 1892, 1893, etc. 



69. Boussingault : From Storer : Agriculture. 



70. Handbook of Experiment Station Work. 



71. New York (State) Agricultural Experiment Station, Bulle- 

 tin No. 1 08. 



72. Voorhees : U. S. Department of Agriculture, Farmers' Bul- 

 letin No. 44. 



73. Liebig : Die Chemie in ihrer Anwendung auf Agrikultur 

 und Physiologic. 



74. Warington : Chemistry of the Farm. 



75. Lawes and Gilbert : Growth of Wheat. 



76. Lawes and Gilbert : Growth of Barley. 



77. Lugger : Minnesota Agricultural Experiment Station, Bulle- 

 tin No. 13. 



78. Lawes and Gilbert : Growth of Potatoes. 



79. Minnesota Agricultural Experiment Station, Bulletin No. 56. 



80. Shaw : U. S. Department or Agriculture, Farmers' Bulletin 

 No. ii. 



81. White : U. S. Department of Agriculture, Farmers' Bulletin 

 No. 48. 



