CONTENTS xiii 



CHAPTER VIII 



THE POWER OF THE SOIL TO ABSORB SALTS 



PAGE 



Retention of Manures by the Soil — The Absorption of 

 Ammonia and its Salts ; of Potash ; of Phosphoric 

 Acid — Chemical and Physical Agencies at Work — 

 The Non-Retention of Nitrates — The Composition of 

 Drainage Waters — Loss of Nitrates by the Land — 

 Time of Application of Manures . • • .211 



CHAPTER IX 



CAUSES OF FERTILITY AND STERILITY OF SOILS 



Meaning of Fertility and Condition — Causes of Sterility: 

 Drought, Waterlogging, Presence of Injurious Salts — 

 Alkali Soils and Irrigation Water — Effect of Fertilisers 

 upon the Textuie of the Soil — The Amelioration of 

 Soils by Liming, Marling, Claying, Paring and Burn- 

 ing — The Reclamation of Peat Bogs . • . 233 



CHAPTER X 



SOIL TYPES 



Classification of Soils according to their Physical or 

 Chemical Nature — Geological Origin the Basis of 

 Classification — Vegetation Characteristic of Various 

 Soil Types : Physical Structure, Chemical Composition, 

 Natural Flora and Weeds characteristic of Sands, 

 Loams, Calcareous Soils, Clays, Peat, Marsh, and Salt 

 Soils — Soil Surveys, their Execution and Application . 271 



APPENDICES 



Appendix I.— Chemical Analyses of Typical Soils . 300, 301 

 „ II. — Bibliography. .... 302 



Index ........ 3°5 



