CONTENTS vil 



Ammonia in rain and drain waters ; Ratio of nitrogen to carbon in 

 the soil ; Losses of nitrogen from soils ; Gains of nitrogen to soils ; 

 Nitrification ; Former views regarding ; Workings of an organism ; 

 Conditions necessary for nitrification ; Influence of cultivation 

 upon these conditions ; Nitrous acid organisms, ammonia-produ- 

 cing organisms, denitrification, number and kind of organisms in 

 soils ; Inoculation of soils with organisms ; Chemical products pro- 

 duced by organisms ; Losses of nitrogen by fallowing rich prairie 

 lands ; Deep and shallow plowing and nitrification ; Spring and 

 fall plowing and nitrification ; Nitrogenous manures ; Sources ; 

 Dried blood, tankage, flesh meal, fish scrap, seed residue, and uses 

 of each ; Leather, wool waste, and hair ; Peat and muck ; Legumi- 

 nous crops as nitrogenous fertilizers ; Sodium nitrate, ammonium 

 salts ; Cost and value of nitrogenous fertilizers. Pages 102-137. 



CHAPTER V 



Fixation. — Fixation a chemical change, examples of; Due to 

 zeolites ; Humus and fixation ; Other compounds of soil cause fixa- 

 tion ; Soils possess different powers of fixation ; Nitrates do not 

 undergo fixation ; Fixation of phosphates ; Fixation a desirable 

 property of soils ; Fixation and the action of manures. Pages 138- 

 140. 



CHAPTER VI 



Farm Manures. — Variable composition of farm manures ; Factors 

 which influence composition of manures ; Absorbents ; Relation of 

 food consumed to manures produced ; Bulky and concentrated 

 foods ; Course of the nitrogen of the food during digestion ; Com- 

 position 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 manure ; Hen manure ; Mix- 

 ing manures ; Volatile products from manure ; Human excrements • 

 Preservation of manures ; Leaching ; Losses by fermentation ; 

 Different kinds of fermentation ; Water necessary for fermenta- 

 tion ; Composting manures ; Uses of preservatives ; Manure pro- 

 duced in sheds ; Use of manures ; Direct hauling to field ; 

 Coarse manures may be injurious ; Manuring pasture land ; Small 



