LIST OF TABLES 



TABLE PAGE 



1. Elements, Symbols, and Atomic Weights 10 



2. The More Important Elements : Occurrence 13 



3. Composition of Silicates 48 



4. Composition of Rock 49 



5. Composition of Fresh Limestone and Residual Clay . . 51 



6. Soils: General Groups . . . . . . . . -55 



7. Recognized Soil Types 56 



8. Relative " Supply and Demand " of Seven Elements ... 59 



9. Composition of Productive and Nonproductive Soils ... 63 



10. Composition of Adobe and Coral Limestone Soils . 65 



1 1 . Composition of Loess Deposits ....... 69 



12. Composition of Ten Residual Soils ...... 73 



13. Mineral Plant Food in Wheat, Corn, Oats, and Clover ... 75 



14. Composition of New York Soils 75 



15. Fertility in Illinois Soils : Surface 82 



16. Fertility in Illinois Soils : Subsurface 84 



17. Fertility in Illinois Soils: Subsoil ....... 86 



18. Composition of Southern Indiana Surface Soils .... 88 

 18.1. Plant Food in Surface Soils of Iowa ...... 91 



19. Composition of Surface Soils of Tennessee ..... 93 



19.1. Composition of Georgia Soil ....... 94 



19.2. Average Composition of Some Texas Soils 95 



19.3. Composition of Some Louisiana Soils 96 



20. Composition of Some Michigan Soils 98 



10. i. Composition of Canadian Soils 103 



20. 2. Certain Plant-food Elements in Illinois Surface Soils . . . 105 



21. Annually Available Fertility in Illinois Soils . . . . .110 



22. Composition of Various Extensive Soil Types of the United States 138 



23. Fertility in Farm Produce . . . . . . . .154 



24. Fertility in Manure, Rough Feeds, and Fertilizers . . . . 157 



25. Pennsylvania Experiments with Lime . . . ... .165 



25.1. Maryland Experiments with Lime . . . . . .167 



26. Experiments with Magnesium Carbonate . . . 171 



27. Losses of Calcium Carbonate from Broadbalk Field . . . 174 



28. Losses of Calcium Carbonate from Hoos Field .... 175 



29. Digestibility of Common Food Stuffs 199 



