After William Temple Franklin returned to Europe in 1792, he left oversight of his financial interests in America in the hands of his intimate friend and fellow land speculator, George Fox. A physician and member of the American Philosophical Society, Fox also took possession of the remainder of Benjamin Franklin's papers, which eventually passed through his son, Charles Pemberton Fox, to the APS. The Franklin-Fox Collection contains 98 items, consisting mostly of letters from William Temple Franklin to George Fox regarding land holdings and finances, and retained copies of Fox's letters to Franklin. The correspondence is fairly relentlessly focused on business matters and rarely contains personal comments, however there are occasional requests for books and two reference to the yellow fever epidemic of 1798 and the death of Benjamin Franklin Bache.

Associates of Benjamin Franklin and his grandson William Temple Franklin, the Fox family of Philadelphia were holders of considerable property in Philadelphia during the eighteenth century and speculated extensively in lands in the northern and western parts of the state. The son of Dr. George Fox, Charles Pemberton Fox inherited the estate Champlost at which the papers of Benjamin Franklin were left in 1790. He donated the collection to the American Philosophical Society in 1840. The legal records that comprise the William Temple Frankln-Charles Pemberton Fox collection relate to real property held by members of the Fox family and to the land holdings and financial interests of George Fox's close friend, William Temple Franklin. The collection includes about 100 deeds for properties in or near Philadelphia and in Luzerne County, Pa., along with a small quantity (about 31 items) of miscellaneous correspondence addressed to George Fox by Gouverneur Morris, Robert Morris, N. Cantwell Jones, Thomas Eddy, and others; and from William Constable and Sir Robert Herries and Co. (17 pieces) relating to the investments of William Temple Franklin.

These letters are mainly business correspondence with his friend William Temple Franklin or are about Franklin's lands and investments in the United States.