1From Benjamin Franklin to Jan Ingenhousz, 30 September 1773 (Franklin Papers)
ALS (letterbook draft): American Philosophical Society I rejoic’d as much as any Friend could do,...
2From Benjamin Franklin to Jan Ingenhousz, 18 March 1774 (Franklin Papers)
ALS : Harvard University Library I have lately been favoured with yours of the 24th past. I am...
3From Benjamin Franklin to Jan Ingenhousz, 12 February[–6 March 1777] (Franklin Papers)
ALS : Yale University Library; incomplete draft and copy: Library of Congress I received your...
4From Benjamin Franklin to Jan Ingenhousz, 26 April 1777 (Franklin Papers)
ALS : Henry Huntington Library I find by your Favour of the 2d Inst. that my Letter to you had...
5From Benjamin Franklin to Ingenhousz, 4[–5] May 1779 (Franklin Papers)
LS : American Philosophical Society I received your kind Letter of last Month, and I forwarded...
6From Benjamin Franklin to Ingenhousz, 22 November 1779 (Franklin Papers)
Copy: Library of Congress I received yours of the 18th. and see with great Pleasure that you have...
7From Benjamin Franklin to Ingenhousz, 2 October 1781[–21 June 1782] (Franklin Papers)
AL (draft) and LS : Library of Congress It is a long time, my dear Friend, since I have had the...
8From Benjamin Franklin to Ingenhousz, [21 June 1782] (Franklin Papers)
AL (draft), press copy of L , and copy: Library of Congress An Attempt to explain the Effects of...
9From Benjamin Franklin to Jan Ingenhousz, 16 May 1783 (Franklin Papers)
LS and incomplete AL (draft): Library of Congress I have before me your three Favours of Feby....
10From Benjamin Franklin to Ingenhousz, 1 June 1783 (Franklin Papers)
ALS : American Philosophical Society This will be delivered to you by an ingenious young Friend...
11From Benjamin Franklin to Ingenhousz, 2 September 1783 (Franklin Papers)
ALS : Mrs. James A. de Rothschild, England (1962) Inclos’d I send you a Copy of a Letter to Sir...
12From Benjamin Franklin to Ingenhousz, 24 December 1783 (Franklin Papers)
ALS : Yale University Library I am greatly indebted to you for Letters. I shall write largely to...
13From Benjamin Franklin to Ingenhousz, 16 January 1784 (Franklin Papers)
ALS : New York Public Library; copy: Library of Congress I have this Day received your Favour of...
14From Benjamin Franklin to Jan Ingenhousz, 23 April 1784 (Franklin Papers)
ALS : Myron Kaller & Associates, Inc., Asbury Park, New Jersey (1989) I did intend to have...
15[From Thomas Jefferson to Jan Ingenhousz, 14 July 1785] (Jefferson Papers)
[ Paris, 14 July 1785. Entry in SJL reads: “Monsr. Ingenhausz medecin de la cour & c. & c. à...
16From Thomas Jefferson to Jan Ingenhousz, 9 July 1787 (Jefferson Papers)
An absence of three or four months on a journey through the Southern parts of France and Northern...
17From Thomas Jefferson to Jan Ingenhousz, 19 June 1788 (Jefferson Papers)
I am late in answering your favor of Jan. 23. but it has not been possible for me to do it sooner...
18From Thomas Jefferson to Jan Ingenhousz, 14 July 1785 (Jefferson Papers)
Doctor Franklin left us two days ago. On his departure he charged me with the inclosed packet to...