of such fields as would best represent the different soils of the State and in case of several applications from one locality the selection was made by lot. The following are the names and addresses of the parties whose fields were thus selected: E. F. Crowninshield, Abbott Run, R. I. H. Hartwell Jencks, Lime Rock, R. I. Elmer K. Watson, Nayatt Point, R. I. Thomas A. H. Tefft, Jamestown (north end), R. I. Courtland P. Chapman, Westerly, R. I. The area under experiment in every case consisted of twenty plots, each containing one-twentieth of an acre. The following diagram shows the arrangement of the plots and the kind and amount of fertilizers applied. PLAN OF EXPERIMENTAL FIELDS Showing the arrangement of plots and the kind and amount of fertilizers apWhere pos plied. Twenty plots, each plot one-twentieth of an acre. sible unmanured strips were left between the plots. 0. No Manure. 1. Nitrate of Soda, 7.5 lbs. 2. Dissolved Bone Black, 17.5 lbs. 3. Muriate of Potash 7.5 lbs. 4. Nitrate of Soda, 7.5 lbs.; Dissolved Bone Black, 17.5 lbs. 5. Nitrate of Soda, 7.5 lbs.; Muriate of Potash, 7.5 lbs. 6. Dissolved Bone Black, 17.5 lbs.; Muriate of Potash, 7.5 lbs.; "Mixed Minerals." 7. Mixed Minerals as No. 6, plus Nitrate of Soda, 7.5 lbs., Ration. 8. Mixed Minerals as No. 6, plus Nitrate of Soda, 15 lbs., Ration. 9. Mixed Minerals as No. 6, plus Nitrate of Soda, 22.5 lbs., full Ration. 6a. Mixed Minerals. Duplicate of No. 6. 10. Mixed Minerals as No. 6, plus Sulphate of Ammonia, 5.6 lbs., Ration. 11. Mixed Minerals as No. 6, plus Sulphate of Ammonia, 11.2 lbs., Ration. 12. Mixed Minerals as No. 6, plus Sulphate of Ammonia, 16.8 lbs., full Ration. 66. Mixed Minerals. Duplicate of No. 6. 13. Mixed Minerals as No. 6, plus Dried Blood, 11 lbs., Ration. 14. Mixed Minerals as No. 6, plus Dried Blood, 22 lbs., Ration. 15. Mixed Minerals as No. 6, plus Dried Blood, 33 lbs., full Ration. 6c. Mixed Minerals. Duplicate of No. 6. 00. No Manure. Where possible unmanured strips were left between the plots. The fields being of different forms the plots on no two fields were of exactly the same length and breadth. In general, the hills were three feet apart in the row and the rows from three to three and a half feet apart according to the width of the plot. After harrowing, the fertilizer was sown broadcast upon each plot and harrowed in. Care was taken in sowing that the fertilizers should be kept back a little from the edges of the plots and that in harrowing it should not be dragged over upon the unmanured strips or the adjoining plots. The crop selected was Indian corn and the seed, which was furnished by the Station, was alike in every instance. So far as possible the corn was thinned out to four stalks to the hill. The plan of the experiment was not to get the greatest possible yield, nor to see who could grow the most corn with the same amount of fertilizers, nor was it to test methods of cultivation and tillage. OBJECTS OF THE EXPERIMENT. The experiments were planned for three purposes: 1. That of learning, if posssible, in what elements some of the soils of the State are especially lacking. 2. For testing the relative fertilizing value of nitrogen in the various nitrogenous compounds, such as nitrate of soda, sulphate of ammonia and dried blood. 3. To learn something, if possible, of the probable profit or loss from large and small applications of nitrogen to the Indian corn crop. In reply to the question which might be raised at this point: "Why cannot the needs of a soil be determined by a chemical analysis? we quote the following from Bulletin No. 8 of this Station: "It is in general understood that those elements in the soil which are soluble in water are directly available as food for plants, and hence one might suppose that if a given amount of the soil were treated with water and an analysis made of the watery solution, that this would show exactly how much available plant food is present in the soil. The facts of the case are, however, that the roots of plants are able to take even more plant food from the soil than that which water alone can dissolve. The ends of the little rootlets have been shown to be acid, and where plants are growing upon a limestone soil it is a very easy matter to find some stone over the surface of which the growing rootlet of some plant has furrowed its channel. Thus then the plant roots are acid at their extremities and their power to extract plant food from the soil is greater than that of water. If now some acid could be selected which would act in the same way and with the same strength as the plant roots, then we should be in condition to determine absolutely the amount of food which the plant can get. This chemists have vainly attempted to do, but there is little probability that it ever can be done. If an analysis is made of the solution obtained by treating the soil with a strong mineral acid, one may learn whether some elements are totally lacking or not and in what relative quantities they are present. The facts of the case are that practically all agricultural soils contain more or less of all the elements of plant food, yet such analyses may be very misleading, from the fact that in a given case such an analysis would show the presence of large amounts of phosphoric acid, while in reality this same phosphoric acid might be in such an insoluble form that practically none of it would be available to the plant. As further complicating the whole question of soil analysis must be mentioned the fact that not only do plant roots have an acid reaction, but from the recent investigations made by Prof. Paul Wagner, at Darmstadt, Germany, it appears that even among plants of the same general character, the feeding or dissolving power of the roots is a varying one. In the case of wheat, barley, oats and rye, it was found that the feeding power as we choose to term it, showed wide variations, and that the oat stood out in marked contrast to the rest as having exceptional power to extract potash from the more insoluble potash compounds in the soil. From this it will be seen that if the chemist could find some acid which would act in the same way and with the same strength as a given plant, we should then have no assurance that this would be any real measure of the amount of plant food which some other plant could extract from the same soil. If, then, a soil analysis is often of little or no value, the practical question presents itself: How can the needs of a soil be determined? This is a problem which several of the agricultural experiment stations have been trying to solve by letting plants answer the question for themselves. For this purpose several plots of land are laid out; one is fertilized with potash alone, one with phosphoric acid alone and one with nitrogen alone; then follow combinations of potash and nitrogen, potash and phosphoric acid and phosphoric acid and nitrogen. As a check upon the whole, other plots are left unfertilized and some are furnished with a combination of all these elements." If the soil contains all the elements but potash, in available form, it is only necessary that potash be supplied in order that plants may develop. If both potash and nitrogen are lacking the plant will develop as soon as they are furnished. From such experiments general conclusions may be drawn as to what element or elements are especially lacking. For the purpose of throwing more light upon the relative fertil. zing value of nitrogen in its various combinations, a series of plots, Nos. 6 to 6c. inclusive, as shown by the plan on page 42, were supplied with a like amount of potash and phosphoric acid. These plots were now divided into three groups of three plots each, to the first group of which (plots 7, 8 and 9) nitrogen in the form of nitrate of soda was applied. The second group (plots 10, 11 and |