Oct 13, 2022 - Sale 2617

Sale 2617 - Lot 18

Price Realized: $ 3,000
?Final Price Realized includes Buyer’s Premium added to Hammer Price
Estimate: $ 1,000 - $ 1,500
Falconer, John (fl. circa 1685)
Cryptomenysis Patefacta: Or the Art of Secret Information Disclosed without a Key.

London: Printed for Daniel Brown, 1685.

First edition, octavo, bound in full contemporary speckled English calf, integral blanks A1, A8, & N8 present; ex libris Thomas Kirke, Esquire (1650-1706), with his bookplate pasted on verso of title (Kirke's books were sold at auction after his death in 1706), and C.S. Overy with his bookplate inside front board; 6 3/4 x 4 in.

"Falconer agrees with other cryptographers of his time that the [polyalphabetic] cipher, while secure, is too slow and cumbersome and so not worth the trouble of using. However, for the sake of giving a complete account of the current state of the science of cryptography in his time, Falconer goes on to discuss in detail how to encipher and decipher messages with this type of cipher. What is interesting and more significant is that he makes a solid attempt at cracking this cipher, possibly the first real attack since its invention." (cf. Charles F. Rocca Jr.'s Cryptology Through History and Inquiry; https://sites.wcsu.edu/mbxml/html/section_polyalphabetic_attack1.html)

Falconer's first strike against polyalphabetic ciphers later morphed into more sophisticated computation in the hands of Charles Babbage and Friedrich Kasiski.

Wing F-296; ESTC R6319; Term Cat. II 137.