24 BOARD OF AGRICULTURE. 



and produce plants almost in any quantity desired, without 

 regard to the ordinary variations of the seasons. This was 

 one of the subjects to be investigated, among others of kin- 

 dred nature. This brings me properly to the su])ject of my 

 address to-day, — experiments in feeding plants. 



I see a few faces here that I did not see a year ago in West- 

 field, and that you may understand the work that has been 

 performed in the College, it is necessary that I should, in as 

 few words as possible, say something of these experiments 

 prior to the year 1875. These experiments began in 1869. 

 The first point to be ascertained was, whether certain ele- 

 ments of plant-nutrition — prepared in a certain way and 

 given to the plants — Avould produce plants. Those experi- 

 ments were tried four years, and it was found by using the 

 ordinary materials known to everybody, — nitrogen, potash, 

 phosphoric acid, soda, magnesia, etc., in certain forms, on 

 soils that were absolutely sterile, — plants could be produced 

 perfect in all their parts. That was the first point to be 

 ascertained. Then to ascertain whether it was needful for 

 the farmer, with such soils as were within our reach, to use 

 all the elements of plant-nutrition, or whether the soil could 

 be relied upon certainly to provide certain elements in sufii- 

 cient abundance so that the farmer need not apply them. 



The experiments for four years seem to indicate that, with 

 such soils as we Avere usino-, cratherinor them on the Colleo^e 

 farm and for miles around, we need not apply to the plant 

 carbon in any form, state or condition ; that that was pro- 

 vided by nature, and always would be ; that we need not feed 

 any other organic element of nutrition but nitrogen ; that 

 nature had not provided nitrogen in sufiicient abundance, and 

 that we must apply it. Among the mineral elements of the 

 soil, it was found that we need only use potash and phosphoric 

 acid for our vegetable crops. There were one or two crops 

 where we decided that we should use, not only potash and 

 phosphoric acid, but magnesia. Tobacco was one, oats was 

 another, where we decided that it was necessary to use mag- 

 nesia ; but for the ordinary crops on such soils, mark you, 

 as we had to experiment with, nitrogen, potash and phos- 

 phoric acid were the only elements needed to be used. And 

 we also noticed that there was a remarkable relation existing 



