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It is a notorious fact, well known to every one who has had opportunities of making observations, that in those parts of the United States where the operations of farming have been confided mostly to slaves, the lands are exhausted of their fertility and have become barren and unproductive. Some lands are now in this condition, which were originally the finest in the United States. Eastern Virginia is a good sample of the effects of slave labor on the fertility of lands. This all results from the ignorance, carelessness and inattention of those to whom the operations of farming are confided. All soils are capable of improvement by judicious culture, and the interests of farmers, individually and collectively, as well as the interest of every American citizen, requires at their hands to so cultivate their lands as to augment their fertility; and not solely with a view to their present productiveness. It is a duty incumbent on them as good citizens; a duty they owe to themselves; to their posterity; to the nation; to the world.