This has been brewing for a long-time. Hugh Garland is figure in antebellum Southern intellectual thought. He was born in western Virginia (around Lynchburg) in 1805. Graduated from Hampden-Sydney College in 1826, then spent a few years in ancient language in Hampden-Sydney College, then attended law school at University of Virginia. He was in the House of Delegates in Virginia 1833 to 1838; he was at Clerk of the US House of Representatives 1839 to 1841. Then was Petersburg from 1838 to 1846. A number of orations survive, including (1) temperance society and (2) the funeral oration for Andrew Jackson. Then he and Anne Burwell Garland along with children departed for St. Louis. In 1850, he published the Life of John Randolph (1850).
Hugh Garland and Lyman Norris was counsel for Irene Emerson for Scott v. Emerson (the former of Dred Scott v. Sandford). A number of Missouri Supreme Courts and two U.S. Supreme Courts were litigated by Garland. Mostly property rights between difference owners and water rights cases, as well.
And a Treatise on Slavery: this is this unpublished. It been sitting there in the Library of Virginia archives since the 1940s. It is major treatise, though incomplete, because he died in 1854.