1882.] EXPERIMENTS WITH FERTILIZERS. 861 



costs me nearly as much as the very fine bone dust with 25 per 

 cent, phosphoric acid and 3 per cent, nitrogen. I suppose the 

 superphosphate acts more quickly, but T have tried the two side 

 by side several years and do not see a great deal of difference in 

 the effects on corn, oats, potatoes, or grass. If I use 300 pounds 

 of each per acre I have from the superphosphate 48 pounds of 

 phosphoric acid, and from the bone 75 pounds of phosphoric acid 

 and 9 pounds of nitrogen. I have got as much corn, oats, and 

 potatoes, the first season from 200 pounds of bone dust as from 

 800 pounds of superphosphate, each being used with other mate- 

 rials, as potash salt, or nitrate of soda, or both, and feel reasonably 

 sure that in most any case I should get as good a yield from 300 

 pounds of bone as from 300 pounds of superphosphate. If I use 

 the superphosphate I have only the 48 pounds of phosphoric acid, 

 about what a corn crop of 50 or 60 bushels would take from the 

 soil. But if I use the 300 pounds of bone, which cost3 very little 

 more, I get just as good a yield, and have the extra phosphoric 

 acid and nitrogen left over. Now I understand chemists to say 

 that the extra phosphoric acid will stay in my soil until future 

 crops take it away, and that although the nitrogen is slippery stuff 

 and gets away pretty easily, still in bone it is pretty stable. So I 

 calculate that bone is cheaper on the long run for me than super- 

 phosphate." 



" But ' circumstances alter cases.' I was talking with a man 

 from Long Island the other day who told me he had to pay $45 

 per ton for fine bone dust, while we get the finest sawings for .S3 7. 

 Still even at $45, taking into account the nitrogen, I think I 

 should use the bone dust, though others might find the superphos- 

 phate preferable." 



Mr, Fairchild has some experience with commercial fertilizers 

 and stable manure together, and like many other experimenters 

 whose conclusions have come to my knowledge, he thinks the 

 proper use of commercial fertilizers is to supplement the manure 

 of the farm. 



He says that if he is going to depend on stable manure alone 

 for corn, he "would not think of using less than 36 loads (on a 

 wagon that carries about 30 bushels) per acre. But 12 loads or 

 one-third of what I should call a fair dressing, with the addition 

 of 200 pounds of bone-dust, and 150 pounds of muriate of potash 

 which cost me $7.00, has brought, during the past three seasons 

 on three different fields, each of very poor land, an average of 65 



