11Thomas Jefferson to Charles Willson Peale, 8 May 1816 (Jefferson Papers)
agriculture; threshing machines [index entry]
12Thomas Jefferson to Archibald Thweatt, 16 March 1817 (Jefferson Papers)
agriculture; threshing machines [index entry]
13Thomas Jefferson to Alexander Hepburn, 7 August 1819 (Jefferson Papers)
agriculture; threshing machines [index entry]
14Thomas Jefferson’s Notes on Alexander Hepburn’s Poplar Forest Materials List, [ca. 8 October 1819] (Jefferson Papers)
agriculture; threshing machines [index entry]
15Thomas Jefferson’s Calculation of Timber Needed by Alexander Hepburn at Poplar Forest, [ca. 8 October 1819] (Jefferson Papers)
agriculture; threshing machines [index entry]
16Thomas Jefferson to John H. Peyton, 17 December 1819 (Jefferson Papers)
agriculture; threshing machines [index entry]
17Thomas Jefferson to Joel Yancey, 12 May 1820 (Jefferson Papers)
agriculture; threshing machines [index entry]
18Thomas Jefferson to Alexander Hepburn, 20 May 1820 (Jefferson Papers)
agriculture; threshing machines [index entry]