US crypto expert Jim Gillogly broke over 1,000 transposition cryptograms created by IRA activists in the 1920s. Only one of these messages remained unsolved. Now, it has been broken by Richard Bean from Brisbane, Australia.
20 years ago, Jim Gillogly, a great codebreaker and reader of this blog, created three crypto challenges – a Playfair, a Double Playfair, and a Double Column Transposition. Can you solve them?