Drinker's Alley, ran east-west from (Biddle numbering) #108 N. Front St. to #119 N. 2nd St. between Arch and Race Sts. This small alley still exists, just to the north of Elfreth's Alley, though there are no houses (and no 18th century structures) in it. Despite its appearance many times in period sources by no other name than Drinker's Alley, the 1785 directories have no listings for Drinker's Alley. Given only two addresses and the presence of John Flintham, this may have been what MacPherson referred to as Clifton's Alley, though a single match-up between the 1785 and 1791 listings is grounds only for speculation; many people had moved in that interval, and many had children or parents by the same name as them.
This street should not be confused with Drinker's Court, which ran and still runs south from Union (now Delancey) Street between (modern) #236 and #238.
(1791) [No #] Drinker's Alley, Flintham, John, cooper
(1791) [No #] Drinker's Alley, Ruddow, William, house carpenter