Cryptomenysis patefacta; or, The art of secret information disclosed without a key. Containing, plain and demonstrative rules, for decyphering all manner of secret writing. With exact methods, for resolving secret intimations by signs or gestures, or in speech. As also an inquiry into the secret ways of conveying written messages, and the several mysterious proposals for secret information, mentioned by Trithemius, &c
A 1685 London treatise on cryptography by John Falconer, published by D. Brown, intended for readers interested in deciphering secret writing and signals. The single picture is a bookplate of Steuart of Allanton, showing a heraldic shield with a crest, flanked by two rampant lions, a motto scroll above and below, and the owner's name engraved beneath.
