590 SELECTIONS FROM ADDRESSES. 



The ready elucidation of such facts by agricultural chem-" 

 istry, was this : The soil was originally deficient in lime. Its 

 use was followed by an immense augmentation of such pro- 

 ducts as required a calcareous component, and this increase 

 brought into requisition other essentials, as phosphoric acid, 

 occasioning also the exhaustion of these. When these were 

 all removed, of course the lime was not adequate, and the true 

 medication would be determined by ascertaining what was 

 then wanting and adding it. While the crops were small, the 

 now missing ingredients would have eked out the products 

 through a long series of years, so that if the land has been 

 really impoverished, it is because its best portions have been 

 turned into money. 



It is a fortunate circumstance in the aspects of the agricul- 

 tural future of the world, that those elements of the valuable 

 plants which are most essential, and most liable to be removed 

 by a succession of crops, are such as will be replaced without 

 difficulty. The world will now be searched, as it never has 

 been before, for the magazines in which nature or accident has 

 stored up these precious deposits. In the immense aggrega- 

 tions, some of which are known, and many of which are yet to 

 be discovered, of guano, which is nothing in fact but the resi- 

 diuum of fish, digested in the stomachs of water fowl, and 

 then allowed to undergo farther changes and chemical recom- 

 positions under pressure, heat, and the absence of any solvent 

 rains ; — in the excrementitious matters of large cities, formerly 

 turned as noxious and inconvenient refuse into the currents of 

 great rivers or into the tides of the ocean, but now in the pro- 

 cess of being most carefully preserved and applied to agricul- 

 tural uses ; — in the natural marl beds, which contain many 

 valuable elementary principles, and lastly in immense ledges 

 of phosphate of lime, which have been discovered and opened 

 in New Jersey, and which doubtless will be found in other 

 regions, — in all these we see abundant resources to supply the 

 consumption of the most precious ingredients. In fact, these ele- 

 ments are not annihilated in the using. The acids and allialis 

 and other elements which make this year the turnip, then the 

 human being, then the grain, then the horse or the ox, are 

 never lost. There is but a series of rotations, and when it is 

 fully understood that these components are worth saving, all 



