Part III.] OR POISONED BY VEGETABLE GROWTH? 
165 
organic matters absorbed from the soil by par¬ 
ticular plants, while the land is bearing one sort 
of crop it may be lying 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 chemistry, enriches, not impo¬ 
verishes, the soil. 
Akin to the question of excretion from the Sociability of 
. . n , ... plants a fancy 
roots is that of the sociability of plants; and I 
have no more faith in the sociability of plants 
than in excretion from the roots. That par¬ 
ticular plants grow best on particular 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 refer¬ 
ence 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 
M 3 
