FACTORS OF AGRICULTURAL PRODUCTION 183 



experience and the common sense of farmers everywhere, and 

 it ought to go a long way toward disabusing the public mind of 

 the absurd notions taught by certain long-distance farmers, who 

 are telling us nowadays that more intensive cultivation, smaller 

 farms, etc. are the solution of all our agricultural problems. 



Some very clear and tangible illustrations of the operation of 

 this law of diminishing returns are furnished also by certain ex- 

 periments in wheat growing at Rothamstead, where the invalu- 

 able work of Sir John Lawes was carried on. Five plots of land 

 of approximately equal fertility were treated alike, except that 

 different quantities of nitrogen were applied, increasing the 

 dose of this particular ingredient by 43 pounds, as follows i 1 



According to this table diminishing returns are secured after 

 the first dose of 43 pounds of nitrogen is applied, as shown 

 in the last column. That is to say, the second increment of 

 43 pounds (Plot 7) adds a little less to the product than the 

 first: dose (Plot 6) added to that which preceded, and the third 

 dose (Plot 8) still less, etc. The gain in Plot 16 over that in 

 Plot 8 was so slight as to be obviously unprofitable, the f of a 

 bushel increase not being sufficient to pay for the 43 pounds 

 increase in nitrogen. Therefore this plot was discontinued, 

 but the other four were continued for forty-eight years, with 

 average results as follows : 



1 These figures are taken from a most excellent article by Eugene Daven- 

 port, dean of the College of Agriculture in the University of Illinois, in 

 Baili y's Cyclopedia of American Agriculture. The Macmillan Company. 



