1Thomas Jefferson to George Jefferson, 4 November 1811 (Jefferson Papers)
Peacock, David; plows of [index entry]
2George Jefferson to Thomas Jefferson, 7 November 1811 (Jefferson Papers)
Peacock, David; plows of [index entry]
3Gibson & Jefferson to Thomas Jefferson, 12 February 1812 (Jefferson Papers)
Peacock, David; plows of [index entry]
4Thomas Jefferson to Patrick Gibson, 1 March 1812 (Jefferson Papers)
Peacock, David; plows of [index entry]
5Thomas Jefferson’s Notes on the Peacock Plow, October 1814 (Jefferson Papers)
Peacock, David; plows of [index entry]
6Thomas Jefferson to Jeremiah A. Goodman, 6 January 1815 (Jefferson Papers)
Peacock, David; plows of [index entry]