1Thomas Jefferson to Thomas Bruff, 7 June 1812 (Jefferson Papers)
inventions; perpetual-motion machine [index entry]
2Enclosure: Drawing of Charles Redheffer’s Perpetual-Motion Machine, [ca. 30 November 1812] (Jefferson Papers)
inventions; perpetual-motion machine [index entry]
3Thomas Jefferson to Robert Patterson, 27 December 1812 (Jefferson Papers)
inventions; perpetual-motion machine [index entry]