1To Benjamin Franklin from Jan Ingenhousz, 15 November 1776 (Franklin Papers)
ALS : American Philosophical Society; duplicate: Staatsbibliothek Preussischer Kulturbesitz, West...
2To Benjamin Franklin from Ingenhousz, 23 June 1783 (Franklin Papers)
ALS : American Philosophical Society This is only to accompany the adjoin’d lettre of mr....
3To Benjamin Franklin from Ingenhousz, 29 April 1783 (Franklin Papers)
ALS : American Philosophical Society The bearer of this, Mr. james Robertson, being arrived at...
4To Benjamin Franklin from Ingenhousz, 1 September 1783 (Franklin Papers)
ALS : American Philosophical Society The inclosed note and bill of exchange of 150 florins on...
5To Benjamin Franklin from Ingenhousz, 26 February 1783 (Franklin Papers)
ALS : American Philosophical Society You will have recieved my last, by which I asked you leave...
6To Benjamin Franklin from Jan Ingenhousz, 7 February 1781 (Franklin Papers)
ALS : American Philosophical Society I wrote you a lettre some weaks ago containing an account of...
7To Benjamin Franklin from Ingenhousz, 15 June 1778 (Franklin Papers)
ALS : Historical Society of Pennsylvania I recieved your kind lettre dated juin 8 and thank you...
8To Benjamin Franklin from Ingenhousz, 29 August 1781 (Franklin Papers)
ALS : American Philosophical Society Give me leave to acquaint you, that I wrote an other letter...
9To Benjamin Franklin from Jan Ingenhousz, 18 November 1779 (Franklin Papers)
ALS : American Philosophical Society I find myself very happy to be in a country, from which I...
10To Benjamin Franklin from Jan Ingenhousz, 23 May 1781 (Franklin Papers)
ALS : American Philosophical Society After having longed such a long while for an answer upon my...