Two postcards from the early 20th century are written in Morse code or something similar. One of these cryptograms is still unsolved.


In 1905, an encrypted postcard was sent from San Francisco to Paris. Can a reader break it?


Today’s crypto mystery is about a postcard written to a noblewoman in 1914. Can a reader solve it?


Eight words and a question mark. That’s the content of an old encrypted postcard from New York City. Can a reader decipher it?


A postcard from 1885 was written in a strange code. Can a reader decipher it?


In the last decade of the 19th century, an unknown person sent three encrypted messages from a place named Bristol. Can a reader decipher these messages?


My readers are pretty good at solving encrypted postcards. However, the two specimens I am going to introduce today look pretty hard to decipher, as the messages are pretty short.


A postcard from 1906 is written in a combination of Morse code, numbers, and letters. Can a reader solve this unusal cryptogram?


An encrypted postcard from the 1870s is written in a strange code. Can a reader solve it?


A postcard from 1909 bears an encrypted message and an unusual spelling of a remarkable rock. Can a reader solve these mysteries?