178 ON FALLOWING. 



not be supported by any chemical principle : n6r 

 can I believe it could ever have proved good in 

 practice. 



It is admitted on all sides, that a vegetable 

 being destroyed and decomposed, and again de- 

 posited on the spot where it grew, adds much to 

 the capacity of the soil ; and, after what has been 

 said, a doubt can scarcely exist whether, if it be 

 exposed in such a manner, during the decompo- 

 sition, to the influence of the sun, air, and light, 

 as to become duly oxydized ; it will add more to 

 the fertility of the soil, than if it were decomposed 

 in a situation immersed in water, or obscured 

 from the light, heat, and oxygene. 



The consumption of vegetables by animals, 

 effects much the same change, as exposure to the 

 sun and air ; that is, by favoring oxydizement or 

 by rendering the substance not only more solu- 

 ble, but reducing it to a state more readily to 

 absorb oxygene ; and particularly when the dung 

 and urine are united: and these changes, aided 

 by the continual turning of the soil by the plough, 

 universally constitute the most effective opera- 

 tions in cultivating the earth. 



As to the loss of a season, and a crop of vege- 

 tables, as food for animals, or as manure to the 

 land; the object of fallowing, on the principles I 

 have explained, may be fully sustained and acted 



