480 ON THE CONNECTION OF GEOLOGY 



happen that the soil produced by their decomposition 

 may occur of very different qualities, in places not very 

 distant from each other. The manner in which the soil 

 is influenced by a difference in the arrangement and po- 

 sition of the strata, will become evident, on comparing 

 districts in which one particular sort of rock lies beneath 

 the surface in horizontal strata, with others in which the 

 solid substratum is composed of various rocks differing 

 in their inclination towards the horizon. In districts of 

 the former kind, the qualities of the soil vary in gene- 

 ral but little ; in such as are of the latter kind, on the 

 contrary, they are often found extremely different. The 

 great diversity of soil seen in England, as well as in 

 Germany, may, in fact, be partly explained by the cir- 

 cumstance, that, in those countries, the nature and posi- 

 tion of the strata vary every where. On the other 

 hand, the great similarity which pervades the soil of 

 Southern Russia, is without doubt produced by a uni- 

 formity in the position and inclination of the limestone 

 which lies immediately under the soil. 



The nature of the principal mass of the strata usually 

 exerts a great degree of influence over the qualities of 

 the soil. When the solid substratum is sandstone, its 

 effect upon the soil is, in general, as evidently seen, 

 though not perhaps in an equal degree, as when it is 

 marl. Exceptions, however, to this rule sometimes oc- 

 cur ; as, for instance, when the principal mass of a rock 

 which resists disintegration in a high degree contains 

 beds that are easily reduced to earth. This is the case 

 with the shell limestone (muschelkalkstein) of Ger- 

 many, the mountains of which are not unfrequently co- 

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