March 7, 1750–July 13, 1750 | Journal Thomas Walker's Journal (1750) In March 1750 (1749 under the Julian Calendar), Thomas Walker and several companions set off through western Virginia into modern-day Kentucky. His journal documents some of the earliest Euro-American impressions of the Cumberland region.
August 14, 1779–August 7, 1780 | Journal Daniel Smith's Journal (1779-1780) In 1779, with other surveyors and adventurers from Virginia and North Carolina, Daniel Smith and Thomas Walker set out to extend the Virginia-North Carolina boundary line far beyond the Cumberland Gap. From August 1779 until August 1780, the men traveled from southern Virginia, to the Falls of the Ohio River, and back to Virginia. In addition to their survey duties, the men worked secretly for Thomas Jefferson, meeting with George Rogers Clark at the Falls of the Ohio River to scout locations for the planned Fort Jefferson.
1780 | Report Report of the Virginia Commissioners, 1780 Daniel Smith and Thomas Walker report to the Virginia Assembly on their mission to establish a line between Virginia and North Carolina.
November 16, 1803 | Letter Thomas Jefferson to Meriwether Lewis, November 16, 1803 Thomas Jefferson updates Meriwether Lewis on political activity around the event of the Louisiana Purchase. Jefferson includes notes from the explorer Truteau that detail population and activities of some native groups living west of the Mississippi.
March 13, 1804 | Letter Thomas Jefferson to William Dunbar, March 13, 1804 Thomas Jefferson thanks William Dunbar for his letter of January 28, promising to forward his paper on the Mississippi River to the American Philosophical Society. Jefferson then writes a detailed discussion of the science of water in a river like the Mississippi. Jefferson also relates his plans for directing surveying parties to the Mississippi and Ohio Rivers, in addition to explorations of the Red and other more southern waterways. Jefferson concludes with speculations on the future of the Lousiana Territory.
April 6, 1804 | Report William Dunbar to the American Philosophical Society, via Thomas Jefferson, read April 6, 1804. The Mississippi River, its delta, and the surrounding region receive detailed attention from William Dunbar in this report forwarded to the APS by Thomas Jefferson.
May 13, 1804 | Letter William Dunbar to Thomas Jefferson, May 13, 1804 William Dunbar thanks Thomas Jefferson for his comments about Dunbar's notes on the Mississippi River. Spain's land sales in Western Florida draw the author's attention and Dunbar offers approval of continuing explorations on America's western rivers, while bemoaning Congress' reluctance to adequately fund such expeditions.
November 9, 1804 | Letter William Dunbar to Thomas Jefferson, November 9, 1804 William Dunbar relates the beginnings of his exploration of the Red River, including ventures into former Spanish territory. He also relates general scientific information of interest to Jefferson.