In 1901 an unknown person sent an encrypted postcard from Iserlohn, Germany, to nearby Arnsberg. Can a reader decipher it?
Once again, my friend Tobias Schrödel, who is a comedy hacker, crypto book expert, and collector, has provided me an encrypted postcard. It’s by no doubt a really beautiful one.
As can be seen, the recipient of this postcard was an unmarried woman named Helene Obermeyer living in Arnsberg, Germany. Arnsberg is located in the Sauerland, a region in Western Germany near the city of Dortmund.
The card was sent by an unknown person staying in nearby Iserlohn (a city today meanly known for its hockey team). Like many other encrypted postcards, this one was apparently sent by a young man to his spouse.
As can be seen, the text on this postcard is encrypted in a pigpen cipher. As readers of this blog certainly know, pigpen ciphers used to be very common. A pigpen alphabet is constructed as follows:
There are many variations of this concept. I don’t know which one was used be the sender of the postcard we are dealing with here.