APPLICATION OF SCIENCE TO PLANT CULTURE. 91 



quite guardedly of the nodules and the micro-organisms and their 

 relation to the assimilating of nitrogen by the plant. But his 

 experiments reported last September, gave still stronger evidence 

 than those of the year before that, somehow or other, the plants 

 did get hold of nitrogen and of the free nitrogen of the air and 

 that in considerable quantities. 



I notice that the account of the meeting says that Dr. Hellrie- 

 gel's paper was received with applause and followed by a lively 

 discussion in which a number of well-known chemists took part. 

 I think their discussion must have been very interesting, for manj' 

 of the gentlemen mentioned were the same with whom I well 

 remember conversing about this very point in one of these same 

 meetings five j-ears ago. Then, the idea that plants could get 

 any considerable quantity of nitrogen directly from the air, was 

 very heterodox. 



There is at present a decided teudenc}' to accept the doctrine 

 that some plants do gather nitrogen from the air. If this doctrine 

 is true we may, when guano and nitrate of soda are gone, use 

 clover to obtain a suppl}' of nitiogen. I have letters full of 

 enthusiasm on this subject from all parts of the country, from 

 Maine to Dakota and Texas. Many are thinking of plant culture 

 and plant food and restoring worn out soil. Perhaps after another 

 ten years I shall be able to speak with more confidence on this 

 subject. 



I was much struck the other day by a forcible remark of a 

 friend, who in speaking of farmers' clubs and the men who 

 support them, said: "Where there is one man talking in the 

 meeting, there are a hundred busily thinking at home." The 

 fact is, that we are in the midst of an awakening of agricultural 

 thought tliat is reall}' phenomenal. With the thinking come 

 improvement, better tillage, better crops, better stock, and better 

 profits, and what is best of all, a higher intellectual, and, I trust, 

 moral life. The agencies that speed this movement, the forms of 

 nutriment on which it thrives, are manilold. With the rest, such 

 men and such work as have been here referred to are doing, I 

 believe, not a little to help the good cause along. The future 

 welfare of our race, material, intellectual, and moral, depends 

 upon the food supply, or, in other words, upon the products of 

 the soil. This in turn reduces itself to a question of the supply 

 of phosphoric acid, potash, and nitrogen. Enough of the first 



