1To Benjamin Franklin from David Hartley: Two Letters, 23 January 1779 (Franklin Papers)
(I) and (II) ALS : American Philosophical Society; transcript: Library of Congress I have...
2To Benjamin Franklin from David Hartley, 18 December 1778 (Franklin Papers)
ALS : American Philosophical Society; transcript: Library of Congress I hope the Exchange will...
3To Benjamin Franklin from David Hartley, 10 December 1778 (Franklin Papers)
ALS : American Philosophical Society; transcript: Library of Congress I recd two days ago notice...