INTRODUCTION. 



THE tendency of modern times towards centralisation, 

 the modern methods of sewage disposal and of culti- 

 vation, involving thorough drainage of our soils, and 

 the so-called " intensive " cultivation of our crops, have 

 all combined to render the function of manures at the 

 present day of greater importance than ever before. 

 While it is true the farmer is no longer as he was 

 a century ago entirely dependent for his supply of 

 manure on that produced on the farm, and while, 

 therefore, farmyard manure can scarcely be looked 

 upon as an absolute essential, inasmuch as it is a 

 bye-product of the farm, and will always continue 

 to be so, a thorough knowledge of its nature and 

 composition must ever remain for the farmer and 

 agricultural student of the highest importance. 



The question of the fertility of the soil is a wide 

 and complex one. It depends on many and various 



