THE ELEMENTS OF SOILS. 6/ 



color to the fields and roads. Besides these fourteen 

 elements, there are at times to be met in soils small 

 quantities of manganese, iodine, and fluorine. 



xrv. SOIL- ANALYSIS. While these fourteen or 

 seventeen elements may be found in nearly all soils, 

 we must not think they can be found in a pure state. 

 All are mingled together in various compounds. The 

 chemist can take a quantity of soil from a field, and 

 tell us just which of these compounds are in that little 

 mass of loam or earth. Such an examination he calls 

 an analysis. The following is an analysis of a good 

 soil, as reported by Professor Lupton of Nashville, 

 Tenn. : 



Percentage. 



Potassium oxide 0.2 



Sodium oxide 0.4 



Calcium oxide, or lime 5.9 



Magnesium oxide, or magnesia 0.8^ 



Iron oxide 6.1 



Aluminium oxide, or aluminia 5.7 



Manganese oxide o.i 



Silicon oxide, or silica 64.8 



Sulphuric acid, or sulphur tri-oxide .... 0.2 



Phosphoric acid, or phosphorus pentoxide . 0.4^ 



Carbonic acid, or carbon di-oxide 4.0 



Chlorine 0.2 



Organic matter 9.7 



Loss 1.4 



100.0 



This analysis is very interesting as showing the com- 

 binations of the elements. Observe how very largely 

 oxygen appears mixed with the other elements. The 



