Frederick Law Olmsted.  A Journey in the Back Country.  New York, 1860.

——.  A Journey in the Seaboard Slave States, etc.  New York, 1856.

——.  A Journey through Texas, etc.  New York, 1857.

——.  The Cotton Kingdom, etc. 2 vols.  New York, 1861.

Sir W.G.  Ouseley.  Notes on the Slave Trade; with Remarks on the Measures adopted for its Suppression.  London, 1850.

Pennsylvania Historical Society.  The Charlemagne Tower Collection of
American Colonial Laws. (Bibliography.) Philadelphia, 1890.

Edward A. Pollard.  Black Diamonds gathered in the Darkey Homes of the
South.  New York, 1859.

William F. Poole.  Anti-Slavery Opinions before the Year 1800.  To which is appended a fac-simile reprint of Dr. George Buchanan’s Oration on the Moral and Political Evil of Slavery, etc.  Cincinnati, 1873.

Robert Proud.  History of Pennsylvania. 2 vols.  Philadelphia. 1797-8.

[James Ramsay.] An Inquiry into the Effects of putting a Stop to the African Slave Trade, and of granting Liberty to the Slaves in the British Sugar Colonies.  London, 1784.

[James Ramsey.] Objections to the Abolition of the Slave Trade, with Answers, etc.  Second edition.  London, 1788.

[John Ranby.] Observations on the Evidence given before the Committees of the Privy Council and House of Commons in Support of the Bill for Abolishing the Slave Trade.  London, 1791.

Remarks on the Colonization of the Western Coast of Africa, by the Free Negroes of the United States, etc.  New York, 1850.

Right of Search.  Reply to an “American’s Examination” of the “Right of Search, etc.”  By an Englishman.  London, 1842.

William Noel Sainsbury, editor.  Calendar of State Papers, Colonial Series, America and the West Indies, 1574-1676. 4 vols.  London, 1860-93.

George Sauer.  La Traite et l’Esclavage des Noirs.  London, 1863.

George S. Sawyer.  Southern Institutes; or, An Inquiry into the Origin and Early Prevalence of Slavery and the Slave-Trade.  Philadelphia, 1858.

Selections from the Revised Statutes:  Containing all the Laws relating to Slaves, etc.  New York, 1830.

Johann J. Sell.  Versuch einer Geschichte des Negersclavenhandels.  Halle, 1791.

[Granville Sharp.] Extract of a Letter to a Gentleman in Maryland; Wherein is demonstrated the extreme wickedness of tolerating the Slave Trade.  Fourth edition.  London, 1806.

A Short Account of that part of Africa Inhabited by the Negroes, ... and the Manner by which the Slave Trade is carried on.  Third edition.  London, 1768.

A Short Sketch of the Evidence for the Abolition of the Slave-Trade.  Philadelphia, 1792.

Joseph Sidney.  An Oration commemorative of the Abolition of the Slave Trade in the United States....  Jan. 2. 1809.  New York, 1809.