EQUILIBEIUM IN SOILS 103 



annually afforded them. We have also to bear in 

 mind that when the accumulation of organic matter 

 has reached a certain point, the conditions for anae- 

 robic fermentation may easily occur during wet 

 weather, resulting in denitrification, and a loss of 

 nitrogen in the form of gas (see p. 41). 



The increased waste as the soil becomes richer is a 

 point which those who farm highly should always 

 bear in mind. To farm highly with profit demands 

 more scientific knowledge and more practical skill 

 than when a lower standard of production is aimed at. 

 The last bushel of corn in a big crop, the last ton of 

 roots, and we may add the last stone in weight gained 

 by a very fat animal, costs far more to produce than 

 any other. When prices run high, it may pay to push 

 production to its utmost limit ; when profits are small 

 it ceutainly does not pay to do so. 



