14 FERTILIZERS. 



elements, nitrogen, potash, or phosphoric acid, of which the 

 soil has the least, will always be the measure of the crop. 



A hundred pounds of potash applied would not give a 

 larger yield than five pounds (and so of the other two 

 elements) if there is not a proportionate increase of the 

 other elements. 



Says Professor Atwater, in his generalizations from over 

 a hundred carefully studied experiments, " Either the com- 

 bined testimony of these experiments, similar ones else- 

 where, and the best experience, are totally false, or chemical 

 fertilizers bring larger, better, and even surer crops than 

 farm manure. . . . Artificial fertilizers rightly used must 

 prove among the most potent means for the restoration of 

 our agriculture." The professor makes this general rec- 

 ommendation : " For general farming, at a distance from 

 the large markets, the chief use of commercial fertilizers 

 should be to supplement the manure of the farm. The 

 right way is, to make the most and best manure that is 

 practicable upon the farm, and piece out with such com- 

 mercial fertilizers as experiments and experience prove 

 profitable. At the same time, there are many cases, espe- 

 cially near cities, where every thing depends on getting 

 the largest and best (and earliest) yield, where the more 

 exclusive use of chemical fertilizers is advisable." This 

 is sound sense ; but I would modify it somewhat by advis- 

 ing to use fertilizers on leachy soil in preference to barn 

 manure, depending on occasional laying-down to grass to 

 improve the texture of such soil. Also, as a rule, to de- 

 pend on fertilizers for the vegetable and grain crops, and 

 give the manure to the grass crop, ploughing under a good 

 sward to enrich the land with humus, when the grass 

 crop is as heavy as a ton to the acre, and not waiting till 

 you can span between the blades. 



The celebrated experiments of Mr. Lawes of Rotham- 



