X CONTENTS 



PAGES 



waters ; Ratio of nitrogen to carbon in the soil ; Losses 

 of nitrogen from soils ; Gains of nitrogen to soils ; Nitri- 

 fication : Former views regarding ; Workings of an organ- 

 ism ; Conditions necessary for nitrification ; Influence of 

 cultivation upon these conditions ; Nitrous acid organisms, 

 ammonia-producing organisms, denitrification, number and 

 kind of organisms in soils ; Inoculation of soils with 

 organisms ; Chemical products produced by organisms ; 

 Losses of nitrogen by fallowing rich prairie lands ; Influ- 

 ence of plowing upon nitrification ; Nitrogenous manures ; 

 Sources ; Dried blood, tankage, flesh meal, fish scrap, 

 seed residue, and uses of each ; Leather, wool waste, and 

 hair; Available organic nitrogen; Peat and muck; Le- 

 guminous crops as nitrogenous fertilizers ; Sodium nitrate, 

 ammonium salts ; Calcium cyanamid ; Cost and value of 

 nitrogenous fertilizers. 



CHAPTER V 



FARM MANURES . . 158-190 



Variable composition of farm manures ; Average com- 

 position of manures ; Factors which influence composition 

 of manures ; Absorbents ; Use of peat and muck as ab- 

 sorbents ; Relation of food consumed to manures pro- 

 duced ; Bulky and concentrated foods ; Course of the 

 nitrogen of the food during digestion ; Composition of 

 liquid and solid excrements ; Manurial value of foods ; 

 Commercial valuation of manure ; Influence of age and 

 kind of animal ; Manure from young and old animals ; 

 Cow manure ; Horse manure ; Sheep manure ; Hog ma- 

 nure ; Hen manure ; Mixing manures ; Volatile products 

 from manure ; Human excrements ; Preservation of ma- 

 nures ; Leaching ; Losses by fermentation ; Different kinds 

 of fermentation ; Water necessary for fermentation ; Heat 



