I transcribed just the Armstrong's but if you'd like a lookup, let me know. Obviously, the content of the letters is not given, just the addressee, date published in the Gazette, and sometimes some sort of address: "Postmaster General Spotswood in 1737 removed William Bradford from the office of Postmaster of Philadelphia and appointed in his stead Benjamin Franklin. Up until that time letters were held at a post office until called for, but Franklin, desirous of improving the system, began the publication of the names of persons for whom unclaimed letters were in the office under his jurisdiction. The first list appeared in Franklin's Pennsylvania Gazette of 21-Mar-1738 and, as a result, addressees, their friends or messengers, picked up much of the mail. These lists, which were printed from time to time throughout the Colonial Period, with occasional lapses, provide a wealth of genealogical information by locating thousands of individuals at various times and, upon occasion, identifying their trade, profession, or military rank. Sometimes the Gazette published lists from towns other than Philadelphia, specifically Chester, Lancaster, New Castle, Wilmington and Trenton. The capital letter designations P, C, L, N, W, T, following the addressee's name signify respectively the post offices in Philadelphia, Chester, Lancaster, New Castle, Wilmington and Trenton in which letters remained unclaimed." For example, all these letters were left in the Philadelphia Post Office although addressed to "Pa", "Forks of the Delaware", "New Castle County", etc.: Thomas P: Forks of the Delaware 18-Mar-1762, Carlisle 13-Jan-1763 & 24-Feb-1763, Wilmingon 13-Oct-1763, New Castle Co. 31-Mar-1763, Pa. 28-Oct-1762 & 2-Feb-1764, Cumberland Co. 15-Mar-1764, Phila. 16-Jul-1767 & 30-Apr-1777. "In instances where specific locality is given, it is understood that the letters were so addressed. The dates which complete each entry indicate the day of publication in the Gazette." ARMSTRONG, Aaron P: Pa. 5-Aug-1762 Andrew P: Cumberland Co. 18-Mar-1762, Carlisle 24-Feb-1763, Phila. 30-Jan-1766. Ann P: Plymouth 20-Oct-1768 Archibald P: New-Castle County 12-Jan-1758 & 3-Jan-1760 Francis L: Peach Bottom 20-Jan-1773. P: Little Britain 13-May-1756, 4-Aug-1763 George P: Cumberland Co. 18-Mar-1762, Phila. 30-Apr-1767. L: Carlisle 14-May-1772 Henry P: Lancaster C. 13-Jan-1763 Col. J. P: Carlisle 31-Dec-1761 James P: Whiteland Township 12-Jan-1758, Cumberland County 3-Sep-1761, Baltimore County 31-Mar-1763, Phila. 16-Jul-1772. L: Peach Bottom 2-Mar-1774. John N: c/o Rev. M'Cannon , Mill Creek Hundred, 4-Dec-1766; 12-Feb-1767. L: 31-Jan-1771 (Colonel); student, Pequea, 2-Mar-1774. P: Conegocheague 3-Jan-1760, Cumberland County 18-Mar-1762, 18-Mar-1762 (Colonel); New Castle County 13-Jan-1763; PA 19-May-1763, 13-Oct-1763. Josiah P: 3-Jan-1776. Martin T: Somerset Court House 1-Sep-1768. Robert P: Pa 2-Feb-1764, Phila. 20-Oct-1768. Samuel P: Phila. 26-Jul-1753 Thomas P: Forks of the Delaware 18-Mar-1762, Carlisle 13-Jan-1763 & 24-Feb-1763, Wilmingon 13-Oct-1763, New Castle Co. 31-Mar-1763, Pa. 28-Oct-1762 & 2-Feb-1764, Cumberland Co. 15-Mar-1764, Phila. 16-Jul-1767 & 30-Apr-1777. W. P: New-Castle Co. 12-Jan-1758. William P: Delaware Forks 24-Oct-1754, , 12-Feb-1761, New Castle 3-Sep-1761, Paxton 4-Feb-1768; N: 29-Nov-1764. L: Carlisle 29-Jul-1772; Juniata, Cumberland Co. 31-Jan-1771 & 19-Dec-1771.