INDEX 



Air supply 30 



Ammonia, production of in soil 

 16, 18 



Bacteria in soil 9 

 Blith and drainage 



76 



6 



92 



Calcium carbonate 

 Chalking 82, 90 

 Clay 4 



Clay soils 40, 86 

 Clay soils, reclamation of 

 Clover 56 

 Coke's system 107 

 Colmatage 82 



Conservation of moisture in soil 

 29 



Derelict land 46, 97 

 Drainage 29, 76 



Edward's system 114 

 Enclosures 52 

 Energy stored in soil 8 

 Exhaustion of virgin soils 46 



Fens, reclamation of 71 



Fertility limits 44 



Food, supply of for plants 32 



Game and the farmer 118, 123 

 Grassland 99 



Hellriegel and Wilfarth 

 Hopkins, Dr Cyril 47 

 Humus 8 



21 



Lawes and Gilbert 13, 58 

 Leguminous plants and nitrogen 



fixation 20, 57 

 Liebig 58 



Live stock and fertility 104 

 Loams 39 



Market gardening 112 

 Marling 52, 80, 90 

 Medieval farming 49 

 Moorland, reclamation of 120 



Nilsson 121 



Nitrates in soil 13 



Nitrification 14 



Nitrogen cycle 25 



Nitrogen, evolution from soil 19 



Nitrogen fixation 20 et seq. 



Pan, removal of 110 

 Partial sterilisation 26 

 Phosphates and fertility 33, 58 



