32 MODERH HIGH FARMING. 



To ascertain the true physical and chemical condition of a soil, 

 the following complete investigation must be undertaken : 



Determination of its density or weight as compared with the 



weight of water. 



Determination of its proportions of sand. 



clay, 

 gravel. 



" powers of absorbing water. 

 " " " holding water. 



" drying capacity. 

 " " powers of absorbing solar heat. 



These operations having been satisfactorily performed, and the 

 physical properties thus accurately known, the study of its value 

 for plant alimentation may be proceeded with in the following order : 



Quantitative determination of its percentage of sulphuric acid . 



" " " " nitric acid. 



" " phosphoric acid. 



" " " nitrogen. 



" " " " lime. 



" " " chlorine. 



" " " " carbonic acid 



" " potash. 



" " " " soda. 



" *' peroxide of iron. 



" " " alumina. 



" " " " oxide of manganese 



" " " " magnesia. 



" " " " soluble silicates. 



Airsifid with the results of this exhaustive investigation, we can 

 dt once find out how the soil may with rapidity and economy be 

 brought to attain the highest degree of fertility. 



