184 BOAED OF AGEICULTUEE. 



bushels. If we consider exportation and loss by city 

 sewage, it would be speaking within bounds to say not 

 one-fourth ever finds its way back to the soil ; but call it 

 two-fifths, and then we have a waste of the fertility required 

 to produce 300,000,000 bushels. The average crop we 

 know to be about thirteen bushels per acre, and ion the sup- 

 position that thirty years would be required to exhaust the 

 wheat-growing soils, we find that to produce the wheat annu- 

 ally lost requires the annual exhaustion of 800,000 acres, 

 about equal to the total tillable land in Massachusetts. If to 

 this we add the corn and other grain largely exported or made 

 into whiskey, tobacco (all of which is burned), cotton, 

 hemp and flax, which draw largely from the soil, we get 

 some idea of the waste annually going on. The Roman 

 provinces are said to have been exhausted by the tribute 

 exacted from them by their conquerors ; but we venture to 

 say that the tribute paid by those conquered provinces to 

 the imperial government was small compared to the tribute 

 America is annually paying to Europe, — drawing from her 

 virgin soil to support the toiling millions of manufacturers 

 in England, France and Germany. 



Let no one suppose that the soil of our Western prairies 

 is inexhaustible. There is no such thing as an inexhaustible 

 soil. The surface of the earth was once barren, its elements 

 all mineral, no humus, no organic matter, no fertility. 

 Nature has been at work millions of years gradually supply- 

 ino; the organic matter and humus which now constitutes its 

 fertility, and it may be remanded back to its natural mineral 

 constituents, and become as barren as the original rock. 



The soil of the West is already exhausted to a considera- 

 ble extent. Even in Iowa complaint is made that the yield 

 per acre is falling off. Old lands are being abandoned and 

 new ones taken up. The average product of wheat per acre 

 in New England is greater than it is in New York, Ohio, 

 Wisconsin, Minnesota, Missouri or Nebraska, and very 

 nearly equal to that in Michigan, Indiana and Illinois. If 

 such is the case now with our 60,000,000 of inhabitants, 

 how will it be when we have hundreds of millions ? 



The tendency of our modern farm machinery and the ap- 

 plication of horse and steam power to agriculture is not only 



