11To Benjamin Franklin from Ingenhousz, 18 October 1777 (Franklin Papers)
ALS : Historical Society of Pennsylvania I rcived yesterday from Madame chaumont the lettre of...
12To Benjamin Franklin from Ingenhousz, 14 December 1777 (Franklin Papers)
ALS : University of Pennsylvania Library; AL (draft): Yale University Library You will be...
13To Benjamin Franklin from [Jan Ingenhousz], 6 March 1778 (Franklin Papers)
AL : Historical Society of Pennsylvania I recieved your kind lettre at Brussels with several...
14To Benjamin Franklin from Ingenhousz, 12 [May] 1778 (Franklin Papers)
Letterbook abstract: Gemeente-Archief, Statserf, Breda To Dr. Franklin in passy that sir john...
15To Benjamin Franklin from Ingenhousz, 14 May 1778 (Franklin Papers)
ALS : Historical Society of Pennsylvania You will have recieved my lettre of May 12th. which I...
16To 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...
17To Benjamin Franklin from Jan Ingenhousz, 5 October 1778 (Franklin Papers)
ALS : American Philosophical Society You will be surprised, that I did not keep my word or...
18To Benjamin Franklin from Jan Ingenhousz, 14 November 1778 (Franklin Papers)
ALS : American Philosophical Society As I was not able to finish as soon as I expected the book I...
19To Benjamin Franklin from Jan Ingenhousz, 1 April 1779 (Franklin Papers)
Letterbook abstract: Gemeente-Archief, Statserf, Breda a Franklin , que le volume des Trans....
20To Benjamin Franklin from Ingenhousz, 9 April 1779 (Franklin Papers)
ALS : American Philosophical Society Since my last of last weak I saw your old femal friend in...