LIME AS A MANPRK. 216 



from the iiuitnuls ki'pl on llic farm. Tlicy know wlnit nianuns cost 

 and what iIk y arc wortli. As a rule, too, such men arc gooil farra- 

 irs, aO'l endeavor to work tUeir land tboroughly and keep it clean. 

 When this is llie case, there can be little doubt that we can often 

 use artitlcial manures to grout advantage. 



" You say," said the Deacon, who had been lookin£j over the 

 tables wliile I was tulkiii;:, " that mixed iinneral manures 

 and 50 His. of ammonia irive 39} bushils per acre. Now these 

 nii.xed mineral manures contain [lota.'^li. .>^oda, mapnrsia, and super- 

 phosphate. And I see where sujierpliosphale was used without any 

 potasli, soda, and ma rnesia, but with the same amount of ammonia, 

 the yield is nearly 46 bushels per :icre. Tiiis docs not say much in 

 favor of potash, soda, and magnesia, as manures, for wheat. Again, 

 I see, on plot 1(V>, 50 lbs. of ammonia, afunf, gives ov(r43i bushels 

 per acre. On plot ll'^ 50 lbs. ammonia mid superpiiosphate, give 

 4fii bushels. Like your father, I am inclined to ask, ' Where can I 

 get tftii ammonui f ' " 



C II A r T E K X X \ I 1 1 . 

 LIME AS A MANURE. 



These careful, systematic, and long-continued experiments of 

 Lawc- and Gill>crt seem to prove that if you have a piece of 

 lanil well prepared for wheat, which will produce, without manure, 

 say 15 bushels per acre, there is no way of making that land pro- 

 duce 30 buslu Is of wheal per acre, without directly or indin ctly 

 furnishing the soil with a liberal supply of available nitrogen or 

 ammonia. 



"What do you mean by directly or indirectly?" asked the 

 Deacon. 



" What I had in my mind," said I, " was the fact that I have 

 seen a good dressing of lime double the yield of wheat. In such 

 a case I suppose the lime decomposes the organic matter in the 

 soil, or in some otlier way sets free the nitrogen or ammonia 

 already in the soil ; or the lime forms compounds in the soil which 

 attract ammonia from the atmosphere. Be this as it may, the 

 facts brought out by Mr. Lawes' experiments warrant us in con- 

 cluding that the increased growth of wheat was connected in some 

 way with an increased supply of available nitrogen or ammonia. 



