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Mercury, or the Secret and Swift Messenger:

Shewing, How a Man may with Privacy and Speed communicate his Thoughts to a Friend at any distance.

London, printed by I. Norton, for Iohn Maynard, and Timothy Wilkins, and are to be sold at the George in Fleetstreet, 1641 Stock Code: 140377
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First edition of this early work of cryptography, guiding the reader through the many ways to disguise their messages, including letter ciphers, but also by using points, lines, mathematical symbols, and musical notation. The book is "not merely a practical guide in the use and decoding of ciphers, but a broadly based discussion of the means of communication, or what today would be called semiotics" (DSB); as of such, "there are good reasons for believing this book to be the first rudimentary attempt at constructing a framework for a universal language and alphabet" (Alston). Wilkins would eventually develop these ideas in his 1668 masterpiece, An Essay Towards a Real Character, And a Philosophical Language.
This copy is from the celebrated computing library of Erwin Tomash (1921-2012), with his booklabel to the front pastedown. A nice provenance - in 1950 Tomash joined the Engineering Research Associates, founded by a group of US Navy codebreakers, which developed military computers to crack code. Tomash's records show he bought the book from Jeffrey D. Mancevice, Worcester, MA, in 1988.

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Octavo (162 x 101 mm). Recent sheep, red moroco label, covers ruled in 17th-century style, speckled edges.


Bound without the initial blank and one of the two terminal blanks. Title annotated in an early hand with author's name "by Jno Wilkins" and "D[ono] D[edit] R.B". Binding lightly scuffed, small patch of residue to title page, 2 cm closed tear to B1, text bound somewhat close to gutter. A very good copy, contents clean.


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