Italian cryptologist Luigi Sacco left behind a text encrypted with a Fleissner grille. Paolo Bonavoglia and Bart Wenmeckers, both readers of this blog, solved it.


In a British censorship manual from WW2 two pictures containing hidden messages are displayed. My readers have now found at least a part of the solutions.


Three weeks ago I blogged about an encrypted telegram that was sent from New York to Tel Aviv in 1948. This cryptogram has now been solved.


Blog reader Bart Wenmeckers has solved a 19th century cryptogram I recently introduced with Hill Climbing. A few diagrams he provided give me the chance to explain how this powerful technique works.


“Who can solve this encrypted book?”, I asked five weeks ago. Blog reader Klaus Tappeiner from South Tyrol, Italy, could. His solution of the Tengri 137 cryptogram is absolutely ingenious.


Charles Dellschau (1830-1923) was a US outsider artist, who left behind fascinating paintings. Some of these contain encrypted texts.


Last week I introduced a cryptogram made with a Fleissner grille. Blog reader Armin Krauß found the solution, although I had made a serious mistake in the encryption process.