SOILS. ol 



den centained 30 per cent, of carbonate of lime. Chaptal 

 analyzed a very productive soil in France, which gave near 

 25 per cent of the same, and seven of organic matter. Tillet 

 even found one, and that the most fertile, which yielded 

 37.5 of carbonate of lime. Some of the best in the Missis- 

 sippi valley, have yielded upon analysis, 20 per cent, of mag- 

 nesian lime ; and of phosphate of lime, two to three per cent. 

 Many other soils throughout the United States, contain an 

 equal proportion of carbonate of lime. Such are always the 

 last to wear out, and the first to recover by the addition of 

 manures, when suffered to remain uncultivated, or in a state 

 of rest. 



