PORTA, Giambattista della.

PORTA, Giambattista della. De furtivis literarum notis

London, John Wolfe, 1591


4to, pp. (xx) 228. Roman letter, woodcut floriated initials, headpieces and tailpieces in prelims. Small woodcut ornament to t-p, numerous illustrations depicting encoding and cyphering systems, including three full-page cypher discs with volvelles and 20 woodcut cypher messages, some with ornamental borders, tables and symbols. Slight age yellowing, a few small light spots to occasional blank margins. A very good, crisp and clean copy in contemporary English limp vellum, yapp edges, traces of ties, slightly detaching, stubs from two contemporary ms. secular documents in English. Contemporary ms. autograph “Gualterus Hawgh, pretium iiis viiid” (3 shillings and 8 pence), bookplate of the English antiquarian William Hanbury of Kelmarsh (1704-1768) to front paste-down.

Most attractive copy of this influential, early work cryptography and secret writing by Porta – beautifully illustrated, with three perfectly working volvelles. This is a page-for-page reprint of the first edition (Naples, 1563), made in London by Wolfe, with a dedication to Henry Percy, Earl of Northumberland, from the Italian publisher Giacopo Castelvetro. In 1591, Wolfe issued two versions of this work: the present one, with his name, place and date of publication, and another one with a false imprint and dedicatory epistle copied from the Neapolitan original. Tomash argues that “both editions were unauthorised and circumvented the rights of the author and the regulations of the Stationers’ Company” (Tomash P101). However, the transcript of the Registers of the Company of Stationers of London attests that Wolfe registered his rights to reprint this work on the 2nd of November 1590, paying a 6 pence fee: “John Wolf entred for his Copie vnder th[e h]andes of master Hartwell and the wardens, De furtivis literarum Notis &c vjd” (Register B, f.267r). It seems plausible that Wolfe, well known for his piracy crimes, first secured the rights to reprint ‘De furtivis’ under his name, then produced a counterfeit issue, probably by modifying some of the copies he had already printed, in order to sell them at a higher price. Although Castelvetro states in the dedication that he ‘corrected’ this edition, the text is identical to the 1563 original.


“Porta was only 28 when, in 1563, he published the book on which his fame as a cryptologist rests. De Furtivis Literarum Notis is an extraordinary book. Even today, four centuries later, it retains its freshness and charm and remarkably—its ability to instruct. (…) Its four books, dealing respectively with ancient ciphers, modern ciphers, cryptanalysis, and a list of linguistic peculiarities that will help in solution, encompassed the cryptologic knowledge of the time. (…) Among the “modern” systems—many of which are probably Porta’s own—appeared the first digraphic cipher in cryptology, in which two letters were represented by a single symbol. (…) Perhaps the full measure of Porta’s remarkable abilities may best be taken by his brash tackling of the toughest problem of Renaissance cryptology —the solution of polyalphabetic ciphers. Despite the high esteem in which these ciphers were then universally held, Porta refused to admit their invincibility and thought out some methods of attack.” (Kahn)


Often referred to as “professor of secrets”, the Neapolitan Giovan Battista della Porta (1535-1615) was a polymath and playwright. He was at the centre of a wide scholarly network including Galileo and known throughout Europe for his works in a multitude of fields: astrology, magic, natural philosophy, optics, alchemy, chemistry, cryptography, meteorology. His plays are considered among the best Italian comedies of his age.


‘Gualtherus Hawgh’ corresponds to the English ‘Walter Hawgh’. We were able to identify at least two men with this name living at the end of the 16th century in England, the official to the archdeacon of Norwich (see F. Blomefield, ‘An Essay Towards a Topographical History of the County of Norfolk’, 1806, p. 659) and a poet (J. Ritson, ‘Bibliographia poetica: a catalogue of Engleish poets’, 1802, p. 401).

USTC 511925; ESTC S101179; STC 20118; Harvard It. 397; Tomash, History of Computing P101. This ed not in Adams, Brunet or Graesse. D. Kahn, The Codebreakers (1967)