EXPERIMENTS AT THE COLLEGE. 149 



degrees. In 1876, we have had sixteen inches of rainfall and 

 a temperature of seventy degrees. Now, gentlemen, it is fair 

 to say, that, notwithstanding all that may be said about chem- 

 ical fertilizers making crops independent of the season, such 

 wide variations in the season as these must effect crops upon 

 any fertilizers or upon any manures. 



I come now to speak of the experiments, and I shall be as 

 short as I possibly can and give you any idea of what the 

 experiments this year have been. 



The old series of experiments has been kept along, but a 

 new series has been commenced, and before I close I shall, in 

 connection with another matter, allude to this new series of 

 experiments. 



Scientists agree, that plants can supply themselves with a 

 proportion of their needed nitrogen from natural sources. In 

 the air there is nitrogen in the form of nitric acid, in the form 

 of ammonia, and then that exhaustless supply of nitrogen, 

 the elemental nitrogen of the air. Without stopping to 

 inquire how it is that plants get their nitrogen from any 

 source, we agree that they do get a portion of nitrogen from 

 these sources. The all-important question to the farmer is, 

 How much ? Nitrogen being the most costly element of plant- 

 nutrition, if it were possible to know how much the different 

 plants and different crops obtained, and to reduce it to rule, 

 many hundreds of thousands of dollars would be saved to 

 the farmer. Therefore, to learn this thing, if it be possible 

 to learn it, a series of experiments was begun this year in 

 this direction. The crops taken were oats and corn to repre- 

 sent the grains, potatoes and mangolds to represent the root- 

 crops, and beans to represent the leguminous crops. To 

 each one of these crops we gave four plots of land. In each 

 case, one plot was planted without the fertilizers, to deter- 

 mine the general effect of the fertilizers ; and the other three 

 plots, while they had the same chemicals precisely, and in the 

 proper proportions, were fed with different proportions of 

 nitrogen. The crop was carefully tended in each case, notes 

 made of the influences acting upon the crop, the condition of 

 the crop as affected apparently by the weather, the crops care- 

 fully harvested, and the record made ; and we have learned 

 nothing, — nothing ichatever. There were sixteen plots, upon 



