Son of Franklin friend and correspondent Joseph Fox. Member of the American Philosophical Society, trustee of the University of Pennsylvania (1789-91, 1812-28); member of Pennsylvania Assembly (1800).
Friend in France of William Temple Franklin, whom he presumably met while both were students at the College of Philadelphia.
Before leaving for London in 1790, William Temple Franklin left the bulk of Franklin’s papers with Fox, from whose hands they later came into the possession of the American Philosophical Society and the University of Pennsylvania.
Married in 1789 to Mary Pemberton; three children (two survived to maturity). Married in 1803 to Mary Dickinson; two children.