When acre has been added to acre till all the fertile land is occupied, the yearly increase of food must depend upon the melioration of the land already in possession. This is a fund, which, from the nature of all soils, instead of increasing, must be...
The elements of social science; or, Physical, sexual, and natural religion ... - Сторінка 291
автори: George R. Drysdale - 1876 - 592 стор.
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