ON THE CHEMICAL CONSTITUENTS OF SOILS. 



237 



31. Surface-soil of a field near Drackenburg ; it 

 produces very bad red clover. 100 parts contain: — 



Silica, with very fine siliceous sand 

 Alumina .... 



Peroxide of iron 

 Peroxide of manganese 

 Lime . . . 



Magnesia . . . • 



Potash combined with silica . . 



Soda, idem .... 

 Phosphoric acid, in combination with lime 

 Sulphuric acid 



Chlorine .... 



Humus and nitrogenous matter 

 Humus, soluble in alkaline carbonates 



92014 

 2-652 

 3192 

 0-480 

 0-243 

 0-700 

 0-125 

 0026 

 0-078 

 a trace 

 a trace 

 0150 

 0-340 



100000 



The cause that clover will not flourish on this soil 

 is probably due to the deficiency of gypsum and 

 common salt. 



32. Surface-soil of a field near Paddingbuttel. 

 This field is particularly adapted for the growth of 

 red clover. 100 parts consist of: — 



Silica and siliceous sand 



Alumina .... 



Peroxide of iron 



Peroxide of manganese 



Lime ..... 



Magnesia .... 



Potash, principally in combination with silica 



Soda, idem .... 



Phosphoric acid . . . . 



Sulphuric acid . ... 



Chlorine (in common salt) 



Humus, soluble in alkaline carbonates 



Humus, with nitrogenous matter 



93*720 

 1-740 

 2-060 

 0-320 

 0121 

 0-700 

 0-062 

 0109 

 0103 

 0005 

 0050 

 0-890 

 0120 



100000 



SOILS IN BOHEMIA. 



33. Surface-soil of a very fertile field in the prov- 

 ince of Dobrawitz and Lautschin. 100 parts gave 



Siliceous sand, with much magnetic iron sand . 4-286 

 Earthy part separated by the sieve . . 95 714 



100-000 



