AND ITS RELATION TO ANIMAL LIFE I2Q 



aerated soil than in a close heavy soil in which 

 there is a great deficiency of air. 



I think this view of the case goes a long way 

 to explain the action of lime on heavy clay 

 soils which in many cases will grow nothing 

 till they have a dressing of three or four tons 

 of lime per acre. Most farmers know that such 

 a dressing of lime will render this heavy land 

 loose and friable like ashes ; at least, I have seen 

 this effect in several cases myself, and there 

 can be no question that there would be a much 

 greater circulation of air in such a soil than 

 there would be in a close heavy soil. 



As there is no question that oxide of iron 

 does take up ammonia from the air, then there 

 appears to be no reason why iron in the soil 

 should not be as thoroughly oxidised as iron 

 on the surface of the soil, providing always 

 that it can get all the air and consequently 

 oxygen it requires ; and if it gets all the oxygen 

 there can be no reason why it should not as 

 readily take up ammonia when in the soil, as 

 oxide of iron does on the surface. 



I remember, for instance, experimenting on 

 two acres of heavy dense land, on which no- 

 thing would grow, by manuring it with four 



K 



