1882.] farmers' convention. 57 



The twenty six experiment stations of Prussia are organized 

 under the Minister of Agriculture, and all their business 

 centers in his office. Since their first establishment some 

 thirty years ago, the European experiment stations have 

 educated a large number of investigators, and the rapidly in- 

 creasing demand has created an adequate supply. They are 

 not all first-class men, but they are all able to earn their 

 wages, and to contribute to the ever-growing fund of positive 

 information. 



What Dr. Sturtevant has said with regard to the need of 

 patient work and repeated trials, cannot be emj^hasized too 

 much. Scientific investigation, the object of which is to find 

 out truth, — bottom-fact which we can rely upon, and which 

 will never "go back on us," — requires always, and especially 

 in agricultural matters, where there is such a complex of 

 causes and factors working together, long-continued, patient, 

 and most careful observations. Whether it is in field experi- 

 ments, or in studies upon the feeding of animals, or in 

 researches which have reference to some point in the nutrition 

 of plants, repetition upon repetition and continual study are 

 needed to bring out a true result. As Dr. Sturtevant has 

 told you, some of the earlier deductions from Mr. Lawes' 

 experiments were misleading. Thirty years ago, the president 

 of the Royal Agricultural Society, Sir Philip Pusey, said, — "Mr. 

 Lawes has demonstrated that nitrogen is necessary for wheat 

 and phosphates for turnips." That was believed to be a truth 

 which Mr. Lawes had ascertained after experimenting for a 

 few years. Now, Mr. Lawes, as you will find if you read his 

 recent writings, or if you look at the results of his experi- 

 ments, is not so certain of that thing. He is only certain 

 that on his land there was a large accumulation of nitrogen in 

 the soil, able to carry on the production of wheat at the rate 

 of sixteen bushels per acre for forty years. He has proved 

 that by having tried it for forty years. There are symptoms, 

 however, that the wheat crop is failing to some extent on his 

 land, so that we can safely assert that if his successors will 

 go on tbere for a thousand years, or two thousand years, or 

 long enough, they will exhaust that nitrogen, and the land 



