EXPERIMENTS OX WHEAT. 193 



soda, and magnesia, the year before, while the other had super- 

 phosphate alone." It turned out, as you see from the table, that 

 the potash, etc., only gave half a bushel more wheat per acre the 

 year it was used, and this year, with 2,000 Ibs. of rape-cake on each 

 plot, there is only a bushel per acre in favor of the potash, soda, 

 and magnesia. 



The next plot, 95, "was also unmanured and was passed by my 

 father without comment. " Ah," said he, on coming to the two 

 next plots, 10 z and 10&, " this is better, what have you here ? " 

 ''Nothing bat ammonia" said I, "and I wish you would tell me 

 which is the best of the two ? Last year 106 had a heavy dressing 

 of minerals and superphosphate with ammonia, and 10a the same 

 quantity of ammonia alone, without superphosphate or other 

 mineral manures. And this year both plots have had a dressing of 

 400 Ibs. each of ammonia-salts. Now, which is the best the plot 

 that had s iperphosphate and minerals last year, or the one with- 

 out?" " Well," said- he, " I can't see any difference. Both are 

 good crops." 



You will see from the table, that the plot which had the super- 

 phosphate, potash, etc., the year before, gives a peck less wheat this 

 year than the other plot which had none. Practically, the yield is 

 the same. There is an increase of 13 bushels of wheat per acre 

 and this increase is clearly due to the ammonia-salts alone. 



The next plot was also a splcndil crop. 



" What have you lierc ? " 



"Superphosphate and ammonia." 



This plot (lla), turned out 35 bushels per acre. The next plot, 

 with phosphates and ammonia, was nearly as good. The next plot, 

 with potash, phosphates, and ammonia, equally good, but no better 

 than lla. There was little or no benefit from the potash, except 

 a little more straw. The next plot was good and I did not wait for 

 the question, but simply said, "ammonia," and the next "ammo- 

 nia," and the next " ammonia." Standing still and looking at the 

 wheat, my father asked, " Joe, where can I get this ammonia ?" 

 He bad previously been a little skeptical as to the value of chem- 

 istry, and had not a high opinion of " book farmers," but that 

 wheat-crop compelled him to admit " that perhaps, after all, there 

 tnijht be some good in it." At any rate, he wanted to know where 

 he could get ammonia. And, now, as then, every good farmer asks 

 the same question: "Where can I get ammonia?" Before we 

 attempt to answer the question, let us look at the next year's ex- 

 periments. The following is the results of the experiments the 

 seventh year, 1849--50. 

 9 



