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THE ROYAL SOCIETY OF CANADA 



which, in their content of N, P and K, must of necessity closely repre- 

 sent them, correspond roughly to the formula 2-1-2 (point 12, on the 

 opposite side of the diagram from the commercial fertilizers). 



Again, it is common practice to apply N, P and K alone, repre- 

 sented by the extreme corners, and mixtures of any two, represented 

 by various points on any of the sides of the diagram. It is hardly 

 right, therefore, to explore the diagram in certain sections to the dis- 

 regard of others. 



It is realized that, with experience, many modifications could be 

 made; but it is felt that some such systematic method of study is 

 required. On such crops, too, as potatoes, it is felt that the usual profits 

 obtained so far out-distance the differences in costs of fertilizers that 

 it will be hard to differentiate which complete fertilizer should be used. 

 This point can be located, in fact would of necessity have to be, with 

 greater nicety in crops where money values are much less per acre than 

 is the case with potatoes. ] j 



Table I. — To Compare Different Forms of N, P 

 (Rotation of three years' duration). 

 Lbs. Elements Per Acre. 



and K. 



