FERTILIZERS. 103 



tatoes could be raised by his fonnula, for it was composed just as 

 Nature compounds the materials when she makes a potato. Nitro- 

 gen is volatile and all the time escaping into the air, and if there is 

 any nitrogen in the soil beyond what has been applied, and the 

 plant begins to gather it, it must gather also phosphate and potash. 

 It is almost impossible that there should be a surplus of nitrogen, 

 unless you fertilize with yard manure. It has been asked, Where 

 is the limit — why not make fourteen hundred as well as four hun- 

 dred bushels? and supply the necessary air, carbonic acid, sunlight 

 and heat. The farmer cannot go farther than Nature will go with 

 him. The points stated by Mr. Moore are nothing new. The 

 speaker was not sure that he knew what M. Ville's theor}^ was, and 

 he would hke to know. 



Mr. Moore replied that it was so long since he read M. Ville's 

 book that he was unable to give an exact statement of his theory, 

 but the book contained an account of experiments in the growth of 

 plants in distilled water and sand, with the addition of the three 

 substances which compose the Stockbridge fertilizers. In regard 

 to the surplus of nitrogen in a soil, he knew that such a thing was 

 possible. He was well aware of the value of nitrogen, and had 

 used large quantities of plaster of Paris to fix it. 



Prof. Stockbridge advised Mr. Moore to apply potash to soils 

 which he suspected to contain nitrogen in excess. The new point 

 with him is, that the best fertilizer for any crop is made by com- 

 pounding nitrogen, potash, and phosphoric acid in available form 

 and in the same proportions as those in that crop when perfectly 

 mature. 



Leander Wetherell read from the translator's preface to M. Ville's 

 lectures on agriculture, as follows: "By adding, according to M. 

 Ville's system, nitrogenous matter, phosphate of lime, and potassa — 

 that is to say, a normal or complete manure — to calcined sand, the 

 seed-wheat being equal to 1, the crop is represented by 23." 



Prof. Stockbridge replied that that was not his theory. M. Ville 

 did not make any statement in regard to mingling the substances ; 

 he did not say that the best manure for wheat would be made by 

 combining these materials in certain proportions. The only rule 

 given is in the first lecture — so many thousand pounds of yard 

 manure are a good dressing for an acre for two j-ears. If of aver- 

 age quality, it will have so many pounds of each constituent, and 

 mineral fertilizers must be combined in the same proportions, but 

 he does not give any attention to the composition of the plant. 



