The Jockey Club was formed in 1766 to promote racing and the breeding of good horses. Many prominent men in Philadelphia were members, including Governor Penn, president of the club, and John Cadwalader, vice-president (JACKSON description begins Joseph Jackson. “Washington in Philadelphia.” Pennsylvania Magazine of History and Biography 56 (1932): 110–55. description ends , 116–17). The meeting on this evening was held at Michael Duff’s tavern on Second Street, and among the visitors attending were GW, Jacky Custis, Lord Stirling, and Gov. Robert Eden of Maryland (JACKSON description begins Joseph Jackson. “Washington in Philadelphia.” Pennsylvania Magazine of History and Biography 56 (1932): 110–55. description ends , facing p. 118).