I. AGRICULTURE AND RURAL ECONOMY. 399 



great value. Most of the investigations upon which the 

 accepted theories of agricultural science are founded have 

 been made in Europe, where circumstances obtain, in many- 

 respects, different from our own. And so long as we depend 

 entirely upon results of European experience to guide our 

 practice, we shall run the risk of falling into error. A num- 

 ber of illustrations of this truth are brought out by these 

 experiments of Storer. 



In the experiments described above it was found that po- 

 tassic manures yielded the best crops, while phosphates and 

 nitrogenous manures did but little good, and in some cases 

 positive harm. The largest crops were obtained with farm 

 and city stable-manure, and with wood-ashes. Nitrate, sul- 

 phate, and carbonate of potash (pearlash) likewise brought 

 large returns. In a summary of comparative results, wpod- 

 ashes proved more efficacious than any other single fertilizer, 

 the yield being larger than with either yard or stable manure. 



Professor Storer concludes that the soil needed potash 

 rather than phosphoric acid or nitrogen. " The addition of 

 potassic manures to the soil manifestly enables the crops to 

 make use of a certain store of phosphoric acid and nitrogen 

 that the land contains. It is clearly shown, moreover, that 

 the amount of available potash in the soil must be very 

 small, since neither the phosphatic nor the nitrogenous ma- 

 nures by themselves, nor mixtures of the two, such as several 

 of the so-called superphosphates are known to be, could en- 

 able the crops to get enough potash from the soil to keep 

 them from starving after the first year." And further, " It 

 is plain that the soil of this field, like those of thousands in 

 New England, needs fertilizers that are rich in potash, and 

 that, under the existing condition of things, no advantage 

 can be gained by applying mere phosphatic and nitrogenous 

 fertilizers to the land. ... If only potash enough be given to 

 this soil, the latter can of itself supply all the other ingre- 

 dients that compose the food of plants, at least for the term 

 of years during which the experiments lasted, and for as 

 many more, of course, as the store of phosphates and ni- 

 trogen may hold out. . . . The crying want of the land is for 

 potash, and potassic manures should be applied to it to the 

 well-nigh complete exclusion of all other fertilizers until an 

 equilibrium can be reached." 



