142 



ARE SOILS ENRICHED, IMPOVERISHED, 



V wn 



plants, cannot be doubted, though we are quite in the 

 dark about it. And as regards the peculiar inorganic 

 matters absorbed from the soil by particular plants, 

 while the land is bearing one sort of crop it may be 

 ing fallow, and collecting them, by disintegration, for 

 another sort. 



In this way rotation is of service in man's cropping ; 

 but in those farms or estates which God Almighty 

 keeps in his own hands, where of all that is grown 

 nothing is abstracted, vegetable growth, by its chemis> 

 try, enriches, not impoverishes, the soil. 

 Sociability Akin to the question of excretion from the roots is 



of plants n ^ iti 



a fancy. that of tlic sociaoikty of plants ; and I have no more 

 faith in the sociability of plants than in excretion from 

 the roots. That particular plants grow best on particu- 

 lar soils, and in particular climates, is clear ; though 

 Nature has not grouped her flora or her fauna solely in 

 reference to soil and climate — that is, in reference to 

 the agreement or disagreement of the physiological 

 constitutions peculiar to the plants or animals, with the 

 physical conditions existent in each district of the globe. 



Were it so, that is, were the same species of plants 

 and animals always found under the same physical 

 conditions, it might, with more reason, be argued (as 

 has been argued by Lamarck) that vitality itself is the 

 mere result of physical conditions — that the different 

 constitutions of plants and animals are the result of dif- 

 ferent physical conditions — that the different species 

 are mere changes of form and organisation resulting 



