I'll answer my own question. Using the very detailed Chicago Postal Markings and Postal History written by Leonard Piszkiewicz (2006), I have determined that the F.D. stands for Foreign Division. This particular CDS was in use from 1910 to 1928. As is often the case with philatelic research, another question rears its head: Why did this cover pass through the Chicago post office's Foreign Division at all, given that it involved no foreign address?
Could it be as simple as a clerk picking up and using the wrong canceller? I readily admit that I have no idea what it was like at the Chicago PO in 1926, but it was my initial thought!
TomD
I haven't been able to find out what the "F.D." in the duplex cancel on the cover below stands for. It's probably embarrassingly obvious but my searching so far hasn't answered the question. Any help would be appreciated. (The cover is interesting in part because this first flight for CAM 3 took place on May 12 (see cachets) but the postmark is for the day before.)
re: "F.D." in Chicago 1926 Duplex Cancel
I'll answer my own question. Using the very detailed Chicago Postal Markings and Postal History written by Leonard Piszkiewicz (2006), I have determined that the F.D. stands for Foreign Division. This particular CDS was in use from 1910 to 1928. As is often the case with philatelic research, another question rears its head: Why did this cover pass through the Chicago post office's Foreign Division at all, given that it involved no foreign address?
re: "F.D." in Chicago 1926 Duplex Cancel
Could it be as simple as a clerk picking up and using the wrong canceller? I readily admit that I have no idea what it was like at the Chicago PO in 1926, but it was my initial thought!
TomD