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

Over the last few years, I frequently blogged about encrypted postcards. Postcards written in code were quite popular in the early 20th century, when other means of communication (e.g., telephone, telegrams) were not available or expensive. Most of these encrypted messages were sent by young men to their spouses.

Blog reader Thomas Bosbach has now pointed out another interesting encrypted postcard to me. This one is discussed on Reddit.


As can be seen, this postcard was stamped in Newton, Iowa, on March 2, 1906. Newton is a suburb of Des Moines. The card was apparently designed by an artist named Chris N. Krogstad from Menomonie, Wisconsin. A Google search reveals that Krogstad designed a number of different postcard motives at that time.

The ciphertext looks quite unusual. It’s a mixture of Morse characters, numbers, and letters. The card bears something that looks like a signature, but it’s not readable. Not much else can be seen on this scan. I don’t know who the sender and the receiver of this postcard were. The rearside of the card is not available in the Reddit forum.

Can a reader decipher this postcard?

Further reading: The NSA crypto museum asks for support: Who can solve these encrypted postcards?

Linkedin: https://www.linkedin.com/groups/13501820
Facebook: https://www.facebook.com/groups/763282653806483/

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Kommentare (3)

  1. #1 Torbjörn Andersson
    Kalmar, Sweden
    30. November 2017

    Continental morse (so it is sometimes hard to tell ‘L’ – which is an extra long dash – from ‘T’ – which is an ordinary long dash) + the following key:
    1=a, 2=e, 3=i, 4=o, 5=u, 6=l, 7=m, 8=n, 9=r

    “Started to your house last night but rain drove me back am in the best of health you will noted(?) my picture”

  2. #2 Thomas
    1. Dezember 2017


  3. #3 Klaus Schmeh
    2. Dezember 2017

    @Torbjörn Andersson
    Congratulations! Great job! Another mystery solved.