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any, the most favorable crop, does not in itself enrich, 

 but in some degree, exhausts the land. The exhaus- 

 tion of the land, however, as experience and obser- 

 vation have fully demonstrated, takes place mainly 

 when the seeds of a plant are allowed to perfect them- 

 selves. The turnip is a biennial plant. It does not 

 perfect its seed before it is consumed. There is a- 

 nother circumstance in respect to the turnip plant, 

 which deserves consideration. 



Plants, it is well understood, derive a large 

 portion of their nutriment from the air. The 

 leaves of plants are their lungs. The leaves of tur- 

 nips expose a wide surface to the atmosphere, and 

 derive, therefore, much of their subsistence and nu- 

 triment from these sources. The broad leaves of the 

 turnips likewise shade the ground, preserve its mois- 

 ture, and prevent, in some measure, its exhaustion by 

 the sun and air. 



The turnips have a farther and ultimate use. 

 Meat and clothing come from animals. The more 

 animals are sustained upon a farm, the more meat 

 and the more clothing. These things bear, of 

 course, a proportion to the number of bullocks, 

 sheep, swine, and poultry which are maintained. 

 The great inquiry then is, what kind of crops will 

 least exhaust the land in their cultivation, and furnish 

 at the same time, support to the largest number of 

 animals ? 



A very large amount of land in England is culti- 

 vated in turnips. Fields of turnips of three, four, 

 and even five hundred acres are sometimes seen, 

 though the common fields are much less ; and it may 



