Thursday 13th November 2025 – Club Meeting – Speaker, our very own Andrew Allen with a presentation entitled ‘Cryptography. The Art of Secret Writing’.
Andrew explained that his fascinating subject can be split into three eras of cryptography: manual methods up to WW1, electromagnetic methods up to WW2, and digital era up to the present day; time did not allow to discuss this third era. Andrew’s excellent presentation started an explanation of the difference between a cipher (replacement of a single letter with another) and a code (using a symbol or number to represent a letter, word or phrase).
Andrew started his presentation by explaining how the most basic cipher works: the Caesar Cipher which just scrambles the alphabet to make decrypting more difficult and how they can be deciphered by using frequency analysis (eg. the commonest letter in the English language is “e”, 12%). He then explained the cypher invented by Blaise de Vigenere which was immune to frequency analysis but was eventually cracked by Charles Babbage. Codes were used to pass messages during the time of Mary Queen of Scots. But it was in the first world war that code books were used extensively to pass messages to avoid enemy scrutiny. One weakness of this system was the logistical problems in making sure that all users were working from the same book. Andrew went on to illustrate his talk with other examples of cryptology such as the Zimmerman telegram which provoked the USA to enter the first world war; the Beale papers where the location of a treasure hoard in Virginia is contained in enciphered papers (never fully deciphered); and the location of Diana Dors’ wealth which she had managed to conceal from the tax authorities and, despite her notes being deciphered, has never been found.
Thursday 6th November 2025 – Walk – Whitegate
The Walking Group took on a 4.5 mile walk in what was a perfect autumn day starting at Blakemere Hall Farm Village. The route went through the Magical Wood into a delightful hidden valley passing the Joshua Tree centre, round the Sandiway lakes onto Whitegate Way, a former railway. Other members were invited to join the walkers in the Village, at the Balkemere Centre, for lunch.