CHAPTER XT. 



Fertilizers Relation between Mechanical and Chemical Methods of Laud 

 Improvement Liebig's Views General Manures Farmyard Manure 

 M. Villes' Views Rothamsted Results Why Farmyard Manure is 

 Esteemed Its Cheapness Artificial Manures Defective Teaching as to 

 Manuring Effects Dependent upon Condition of Soil And of Climate. 



OUR next topic is that of fertilizers. When speaking of 

 the methods of improving ]and I pointed out that we might 

 approach the improvement of the land from the mechanical 

 or textural side, that is to say, by developing the resources 

 inherent in the soil, and by making up its deficiencies in 

 composition by the addition of extraneous matter that is, 

 manuring. Now there is a link connecting the two methods, 

 as is often the case, namely, that of chalking, marling, or 

 claying soils, as means for definitely adding to their wealth 

 in plant food. So it is with liming, which is an important 

 means of increasing the fertility of soils. It is difficult to say 

 whether the benefit from liming is more due to the addition 

 of lime or to a palpable improvement which lime effects in 

 the texture of the land to which it is applied. 



So also in the case of farmyard manure, which is the typical 

 manure of most farmers. We must recognize the fact that 

 farmyard manure acts partly as a direct fertilizer or increaser 

 of plant food, but also by improving the mechanical condition 

 of the ground. I may remind you of the important effect of 

 farmyard dung in mitigating and altering the retentive 

 character of clay soils, and how important it is on such soils 

 that the dung should be applied in a strawy or fresh con- 



