The Executive Committee of the American Anti-Slavery Society, while tendering their grateful acknowledgments, in the name of American Abolitionists, and in behalf of the slave, to those who have furnished for this publication the result of their residence and travel in the slave states of this Union, announce their determination to publish, from time to time, as they may have the materials and the funds, TRACTS, containing well authenticated facts, testimony, personal narratives, &c. fully setting forth the condition of American slaves. In order that they may be furnished with the requisite materials, they invite all who have had personal knowledge of the condition of slaves in any of the states of this Union, to forward their testimony with their names and residences. To prevent imposition, it is indispensable that persons forwarding testimony, who are not personally known to any of the Executive Committee, or to the Secretaries or Editors of the American Anti-Slavery Society, should furnish references to some person or persons of respectability, with whom, if necessary, the Committee may communicate respecting the writer. Facts and testimony respecting the condition of slaves, in all respects, are desired; their food, (kinds, quality, and quantity,) clothing, lodging, dwellings, hours of labor and rest, kinds of labor, with the mode of exaction, supervision, &c.—the number and time of meals each day, treatment when sick, regulations inspecting their social intercourse, marriage and domestic ties, the system of torture to which they are subjected, with its various modes; and in detail, their intellectual and moral condition. Great care should be observed in the statement of facts. Well-weighed testimony and well-authenticated facts; with a responsible name, the Committee earnestly desire and call for. Thousands of persons in the free states have ample knowledge on this subject, derived from their own observation in the midst of slavery. Will such hold their peace? That which maketh manifest is light; he who keepeth his candle under a bushel at such a time and in such a cause as this, forges fetters for himself, as well as for the slave. Let no one withhold his testimony because others have already testified to similar facts. The value of testimony is by no means to be measured by the novelty of the horrors which it describes. Corroborative testimony,—facts, similar to those established by the testimony of others,—is highly valuable. Who that can give it and has a heart of flesh, will refuse to the slave so small a boon?