PRESIDENT HITCHCOCK'S ADDRESS. 167 



The opinion is very prevalent, that there is one particular 

 mineral composition to soils indispensable to the highest degree 

 of fertility, and that the chemist, by analyzing a soil, can tell 

 in what it is deficient, and direct the farmer how to supply the 

 wanting ingredient ; and hence, in the view of most persons, 

 the great importance of an analysis of soils. But I believe that 

 facts do not justify these opinions fully. Certain mineral in- 

 gredients do indeed usually enter into the composition of plants, 

 and must be supplied from the soil. But, as said before, soils 

 differing most widely in composition usually contain enough of 

 all these essential ingredients for the use of the plant ; and it is 

 also found, that some of these ingredients may be substituted 

 for others. The great differences in the fertility of soils de- 

 pend more upon the amount and condition of the organic 

 matter which they contain, and upon their power of absorbing 

 and retaining heat and moisture, and upon their degree of fine- 

 ness or coarseness, than upon their mineral constitution. Every 

 farmer knows that a soil may be too coarse or too fine for good 

 crops, and that it may be too cold; and also that it may 

 abound in organic matter, — that is, such as results from decayed 

 animals and vegetables, — and yet be very barren. And when 

 ashes, or quick lime, or marl, or gypsum, or bone powder, is 

 added, they render the soil fertile, not because the soil is en- 

 tirely destitute of these materials, but because they bring the 

 vegetable matter into such a state that it can be taken up by 

 the roots of plants ; or they make it mellow, or more tenacious 

 of heat or moisture. 



If these views are correct, some important consequences 

 follow. In the first place, the community are expecting too 

 much from the mere analysis of soils. An examination of the 

 condition and amount of organic matter which they contain, 

 and of the condition of the lime, whether as a silicate, car- 

 bonate, or sulphate, is of the most consequence. But I do not 

 believe, that agricultural chemistry is yet advanced enough to 

 enable the analyst to determine, in many cases, precisely what 

 is the ingredient wanting in a soil to render it very fertile. The 

 time may come, perhaps, when this may be done, though not 

 solely, as I believe, by analysis. Let no one, however, hence 



