APPLICATION OF PLANT-FOOD. 41 



should have been glad. I think his system is capable of 

 bringing fertility into Massachusetts, enabling us to raise corn 

 profitably by the purchase of our manures. But how must 

 we apply those chemicals ? We know more about chemistry 

 than we do about almost any other subject connected with 

 agriculture. I will speak now of these agricultural chemicals 

 in a soluble form. We know that when these chemicals 

 become soluble in the soil, the soil exercises a decomposing 

 action upon them ; that they are separated into their com- 

 ponent parts, and while a portion escapes through drainage, 

 another portion remains fixed in the soil ; and we can say 

 with regard to the phosphoric acid fixed in the soil, that there 

 is no escape through leaching. It remains absolutely fixed. 

 The potash is more diffusible, and some of it does leach 

 through the soil, but only to a very small extent. The 

 nitrogen, in the form of nitric acid, escapes very rapidly; in 

 the form of ammonia, it is fixed to a large extent. I also 

 know, from the record of certain experiments with turnips, 

 and also from my own observation of the influence of chemi- 

 cals upon corn roots, that the presence of certain chemicals 

 develops the fibrous matter of the roots. 



Let me quote an experiment where plants grew in cylinders 

 filled with very poor clay earth, in which the chemicals were 

 placed in a symmetrical manner in the soil, — one cylinder 

 had the fertilizers in the centre, another had them arranged 

 around the circumference, etc. It was found that the roots 

 extended without many fibrous branches until they reached 

 the fertilizers, and then they distributed themselves with their 

 innumerable mouths to take up these fertilizers. Now, in 

 growing the corn-crop this year, we placed all our fertilizers 

 upon the surftvce of the land. What was the result? The 

 result was that we had a greater root-growth near the surface 

 than at lower depths. The moisture of the season probably 

 saved us from a total loss, because, when the short drought 

 came this fall, our corn wilted so that the cars huns: down. 

 Now, if those roots had received that nutriment in a lower 

 portion of the soil, they would have been out of the reach of 

 the drought. How, then, can we apply these chemicals, in 

 order to get the l)est effect from them? Evidently, reason 

 answers, "Study the nature of the elements, and apply them 



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