THE CODEBREAKERS

by DAVID KAHN

  91 “perforce commune”: William F. Friedman, “Edgar Allan Poe, Cryptographer,” American Literature, VIII (November, 1936), 266-280 at 267.

  91 “sundry very ancient”: Parallel Lives: Lysander xxvi.2.

  91 Leiden papyrus: F. L. Griffith and Herbert Thompson, The Demotic Magical Papyrus of London and Leiden (London: H. Grever & Co., 1904, 1909), I, 97; III, 105-112. I am grateful to Father Theodore C. Petersen for this and many other references to medieval magical cryptology, in an interview, December 16, 1963, and a letter, December 26, 1963.

  91 Arnaldus de Bruxella: W. J. Wilson, “An Alchemical Manuscript by Arnaldus de Bruxella,” Osiris, II (1936), 220-405 at 345. Wilson’s “Catalogue of Latin and Vernacular Alchemical Manuscripts in the United States and Canada,” Osiris, VI (1939), 1-836, notes passages in cipher at 312, 316, 317, 433, 545.

  91 kabbalah: Gershom G. Scholem, Major Trends in Jewish Mysticism, 3rd ed. (New York: Schocken Books, 1961), esp. p. 17.

  92 “truth stands more firmly”: Babylonian Talmud, Seder Mo’ed, Shabbath, 104a, ed. Rabbi Isidore Epstein (London: Soncino Press, 1938), 501 and note 11.

  92 gematria: Scholem, 100, 127, 135; Gandz, 86, 93; “Gematria,” Jewish Encyclopedia’, “Gematria,” Universal Jewish Encyclopedia.

  92 later writers: Johannes Trithemius (the abbot), Jacques Gohorry, Jacques Gaffarel, Claude Menestrier, Gabriel Naudé, and others. See Thorndike. Andrew D. White, A History of the Warfare of Science with Theology in Christendom (New York: Appleton, 1910), 382-383, for church proscription of magic. The discovery of the arcane writings attributed to Hermes Trismegistus probably intensified the association. I think that Madeleine V.-David makes too sharp a division between cryptology and symbolism in her Le Débat sur les Écritures et l’Hiéroglyphe aux XVIIe et XVIIIe siècles, Bibliothèque Générale de l’école Pratique des Hautes études, VIe Section (Paris: S.E.V.P.E.N., 1965), 17-42, 66. See my section on Trithemius.

  93 ben-Wah shiyya: his book has been translated by Joseph Hammer as Ancient Alphabets and Hieroglyphic Characters Explained (London: W. Bulmer & Co., 1806).

  93 treatise on magic: [Paul] Casanova, “Alphabets Magiques Arabes,” Journal Asiatique, 11th series, XVIII (July-September, 1921), 37-55.

  93 spy letter and misirli alphabet: M. J. A. Decourdemanche, “Note sur quatre systèmes turcs de notation numérique secrète,” Journal Asiatique, 9th series, XIV (September-October, 1899), 258-271 at 267-269.

  93 manuscript on war: Wüstenfeld, “Eine arabische Geheimschrift entziffert,” Nachrichten der Gesellschaft der Wiss. zu Göttingen (1879), 349-355.

  94 Persian model, Ghaznavids: Miss J. R. Watson, letter, November 4, 1964, citing Baihaqi, Tarikh i Mas’udi, ed. Ghani and Faiyad (Tehran, 1324/1945-6), 654-655, 688; C. E. Bosworth, The Ghaznavids (Edinburgh: University Press, 1963), 95.

  94 “he was eloquent”: Evariste Lévi-Provençal, ed., Documents inédites d’Histoire Almohade (Paris: Librairie Orientaliste Paul Geuthner, 1928), 59.

  94 Ibn Khaldūn: The Muqaddimah: An Introduction to History, trans. Franz Rosenthal, Bollingen Series XLIII (New York: Pantheon Books, 1958), II, 391-392. Toynbee, A Study of History, 2nd ed. (London, 1935), III, 322.

  94 qirmeh: Ibrahim el Mouelhy, “Le Qirmeh en égypte,” Bulletin de l’Institut de l’égypte, XXIX (1946-1947), 51-82. H. Kazem-Zadeh, “Les chiffres siyak et la comptabilité persane,” Revue du Monde Musulman, XXX (1915), 1-51, for ciphered forms of numerals in Persian financial accounts.

  94 Qalqashandi: C. E. Bosworth, “The Section on Codes and Their Decipherment in Qalqashandi’s Subh al-a ‘shā,” Journal of Semitic Studies, VIII (Spring, 1963), 17-33, giving large portions in translation preceded by a commentary on Arabic cryptology. This is perhaps the most important single article on the history of cryptology, and I am grateful to Bosworth, of the University of St. Andrews, for sending it to me, and for further information and discussion in letters of November 28, 1963, and January 8, July 24, and August 23, 1964. A colleague, John R. Walsh of the William Muir Institute in Edinburgh, argues strongly in letters of January 26 and February 18, 1964, that there “never was” a science of cryptology among the Arabs. He regards it as significant that Qalqashandi, though an official of the chancellery, had no first hand knowledge of the subject and “was compelled to turn for information to what was probably a merely theoretical treatise by a certain Ibn Duraihim.” Moreover, “Amongst the millions of documents preserved in the Ottoman archives, I have yet to hear of one being written in code.” These are strong arguments, but I feel that the tone of the Qalqashandi-Ibn ad-Duraihim work could have come only from experience with cryptology and that Qalqashandi’s casual reference to “thorough probes into all letters” is too weighty to be denied. Consequently, though moderating Bosworth’s probably extravagant view, at 19, that “the use of codes for administrative and diplomatic purposes became widespread,” I have regarded both cryptography and cryptanalysis as fairly well known in the Moslem world. My text reflects this.

  96 probable beginnings of Arabic cryptanalysis: Bosworth, letter, July 24, 1964; Cambridge Mediaeval History, IV, 290-291, for Arabic grammar.

  97 al-Khalīl: John A. Haywood, Arabic Lexicography: Its History, and Its Place in the General History of Lexicography (Leiden: E. J. Brill, 1960), 20-21, 28, 31.

  97 “Occasionally, skillful secretaries”: The Muqaddimah, II, 391. Parentheses in Rosenthal’s translation have been changed to brackets here; they mean an editorial interpolation of needed sense. I have changed his “decoding” to “cryptanalysis” and his “deciphering” to “solving.”

  98 cipher of abd al-Wahid: Georges S. Colin, “Note sur le système cryptographique du Sultan Ahmad al-Mansūr,” Hésperis, VII (1927), 221-228.

  99 cryptanalysis of monalphabetic substitution: Any book on cryptology in any language will explain how to solve such ciphers in that language. The better expositions are those in the books listed in the Bibliography.

  Chapter 3 THE RISE OF THE WEST

  Citations to Meister, Diplomatischen and Meister, Päpstlichen refer respectively to the two indispensable books by Dr. Aloys Meister, professor of history at the University of Münster: Die Anfänge der Modernen Diplomatischen Geheimschrift (Paderborn: Ferdinand Schoningh, 1902), 65 pages, and Die Geheimschrift im Dienste der Päpstlichen Kurie (Paderborn: Ferdinand Schoningh, 1906), 450 pages. Citations in the form Calendar, Foreign, January-July 1589 refer to a volume in the endless and equally indispensable Calendars of State Papers published by Great Britain’s Public Record Office. Following Calendar comes the name of the series in short title, as Foreign or Venice, and then the dates covered by the particular volume in the series, as January-July 1589. Since this will identify the volume, I have thought it unnecessary to burden these notes with full dates and places of publication and editors.

  PAGE

  106 slow growth: Meister, Pädpstlichen, 2-3.

  106 origins of code: Meister, Päpstlichen, 3-12.

  106 origins of cipher: Meister, Päpstlichen, 12-19.

  107 Lavinde’s manual: Meister, Päpstlichen, 21-22, and 171-176 for the keys. The Lavinde document has sometimes been called the first book on cryptology, but since it is nothing more than a collection of cipher alphabets, it does not deserve that title. Perhaps the oldest modern Western discussion of cryptography, as distinct from its mere use, is the “Occulte Scribendi Modus”—apparently a monalphabetic—in British Museum, Sloane Mss. No. 416, f. 155r, dated April 19, 1455. It is almost certainly the oldest such discussion in English (despite its Latin title).

  107 Mantuan alphabet with Simeone de Crema: Meister, Diplomatischen, 41.

  108 nondiffusion of cryptanalysis: This is the opinion of an expert in Arabic influences on Europe. The probable indigenous origin is my supposition.

  108 use of cipher in secular principalities: Meister, Diplomatischen, 15; Sacco, §133.

  108 homophones for consonants, small code lists: Meister, Päpstlichen, 46-49.

  108 stimulus for cr
yptology: Meister, Diplomatischen, 1; Garrett Mattingly, Renaissance Diplomacy (London: Jonathan Cape, 1955), 11-12.

  109 Venetian cryptologic organization: Meister, Diplomatischen, 16-25; Armand Baschet, Les Archives de Venise: Histoire de la Chancellerie Secrete (Paris: Plon, 1870), 576-579; Calendar, Venice, 1509-1519, Appendix II, Rawdon Brown, “History of Italian Cipher,” lxix-lxxii at lxxi-lxxii.

  109 Soro: Meister, Diplomatischen, 21-23; Meister, Päpstlichen, 30-31; Brown, xix, lxxi; Calendar, Venice, 1509-1519, 293, 1520-1526, 607.

  110 Marco Rafael: Calendar, Venice, 1527-1533, 277. The same document cites a paper on cipher presented to the Council of Ten by Alvise Borgi in 1548, which is not mentioned by Meister.

  110 Florentine cryptology: Meister, Diplomatischen, 42-50.

  110 “is due first place”: Matteo Argenti, in Meister, Päpstlichen, 161.

  110 Machiavelli: Book vi, trans, by a Gentleman of the State of New York (Albany: Henry C. Southwick, 1815), 264-265.

  110 Milan: Meister, Diplomatischen, 25-33, 35 for Modena cipher.

  110 Simonetta: P.-M. Perret, “Les règies de Cicco Simonetta pour le déchiffrement des écritures secretes,” Bibliothèque de l’école des Chartes, LI (1890), 516-525; Bibliothèque Nationale, Ms. italien 1595, ff. 441-442.

  111 Babou, “ofttimes decipher”: Dictionnaire de Biographie Française; Blaise de Vigenère, Traicté des Chiffres (Paris: Abel l’Angelier, 1586), 34v-35r.

  112 Antonio Elio: Meister, Päpstlichen, 50.

  112 “decipher with much facility”: Matteo Argenti in Meister, Päpstlichen, 161.

  112 Bencio: Meister, Päpstlichen, 50; his successors, 51-54.

  112 solution of Philip II cipher: Meister, Päpstlichen, 216, reproduces a “Cifra del Card, di Burgos con il re Philippo, decifrata alii x di febraro 1557 in Bologna.”

  112 Great Vicar of St. Peter: Vigenère, 35r.

  112 Argentis: Meister, Päpstlichen, 54-65, 123-124. Their ciphers and rules are described passim in their manuals, extracts of which are given at 65-113, 148-162, 176-221, 283-445. A good resume of their work is Yves Gyldén, “Cryptologues italiens aux XVe et XVIe siecles,” Revue Internationale de Criminalistique, IV (1932), 195-205; another good review, with some new material, is Pierre Speziali, “Aspects de la cryptographie au XVIe siecle,” Bibliothèque d’Humanisme et Renaissance, XVII (May, 1955), 188-206. I have examined Matteo’s manual in the Chigi Library, Rome.

  114 early Spanish ciphers: Calendar, Spain, 1485-1509, xi-xii, and Gustave A. Bergenroth, “Remarks on the Ciphered Dispatches in the Archives at Simancas,” Ibid., cxxxvii-cxlvi.

  114 Columbus cipher: Pietro Martire d’Anghiera, De Orbe Novo (1530), Decade I, ch. 7, trans, by Francis Augustus MacNutt as The Eight Decades of Peter Martyr d’Anghera (New York: G. P. Putnam’s Sons, 1912), I, 149.

  114 Philip changes ciphers: J. P. Devos, Les chiffres de Philippe II et du Despacho Universale Durant le XVIIe Siècle (Bruxelles: Académie Royale de Belgique, 1950), 61-62.

  115 pattern of Spanish cryptography: survey of the ciphers reproduced in Devos and in Mariano Alcocer’s two articles entitled “Criptografía espanola” in Revista de Archivos, Bibliotecas y Museos, 3rd época, XXV (October-December, 1921), 628-640, and in Boletín de la Academía de la Historia, CV (July-December, 1934), 337-460, and in Miguel Gomez de Campillo, “De cifras,” Boletín de la Real Academía de la Historia, CXXIX (October-December, 1951), 279-307, and of photocopies obtained from Spanish archives. Joaquín Carmona, Tratado de Criptografía (Madrid: Sucesores de Rivadeneyra, 1894), lists, 181-192, official keys preserved at the Archivio General de Simancas.

  115 nomenclators for Spanish America: Guillermo Lohmann Villena, two articles entitled “Cifras y claves indianas,” Anuario de Estudias Americanas, XI (1954), 285-380, and XIV (1957), 351-359.

  115 Cortés: “Carta de Hernán Cortés, Marques de Valle, a su pariente y procurador ad litem el Licenciado Francisco Núnez, México, 25 de Junio de 1532,” Anales del Museo Nacional de Arquelogia, Historia y Etnografia, 4th época, III (1925), 123-130, for letter in cipher; “La carta cifrada de Don Hernán Cortés,” Ibid., 436-443 for solution.

  116 Despacho Universal: Devos, 20, 72.

  116 suppression of decipherments, errors: Bergenroth, cxlv.

  116 no Spanish cryptanalysis: Neither actual solutions nor reports of them from this time appear in the literature on Spanish cryptology, though two very short treatises on elementary cryptanalysis, dating from the 15th and 16th centuries, are reprinted in Carmona, 200-202.

  116 Viète’s life: Encyclopaedia Britannica; Biographie Universelle; Tallement des Réaux, Les Historiettes, chapter entitled “Viète,” Bibliothèque de la Pléiade (Paris: Librairie Gallimard, 1960), I, 191-192, notes at 872-873; Jacque-Auguste de Thou, Histoire Universelle, trans, from 1604 Latin original (London: 1734), XIV, 164-166; Frédéric Ritter, François Viète: inventeur de l’algèbre moderne. 1540-1603. Notice sur sa vie et son œuvre (Paris: Revue Occidentale, 1895), 21-23, who mentions that in February, 1603, Viète addressed to Sully a memoir on cryptanalysis; I cannot find it in Sully’s papers.

  116 Farnese solution: Devos, 59.

  117 Moreo plaintext: quoted in Bazeries, 222-232, with citation to original printed document in Bibliothèque Nationale, Les 500 de Colbert, No. 33.

  117 Moreo nomenclator: Devos, 328-334.

  117 bits and pieces: in Viète’s letter to Henri, quoted in Bazeries, 220-222.

  117 Ivry: Auguste Poirson, Histoire du Règne de Henri IV (Paris: Didier, 1862), I, 171-172. Neither Viète nor his solution are mentioned.

  117 “And do not get anxious”: in Bazeries, 220-222.

  117 “He had just told me”: Baschet, 576-579. Mocenigo’s report was the one of June 5, 1595.

  117 della Caselle cipher: André Lange and E.-A. Soudart, Traité de cryptographie (Paris: Librairie Félix Alcan, 1925), suggest, at 34, that this is a Cardano grille. If so, Viète’s comment that “For that, you have to skip a lot” might be taken as an indication that he knew the cipher and perhaps could solve it. Mocenigo’s remark that “he only knew portions of it” does not necessarily militate against this view. Meister does not mention any grille ciphers having been used by Venice, though they were used elsewhere.

  118 Spanish complaint at Rome and its boomerang: de Thou, XIV, 166: “Mais tout l’avantage qu’ils retirèrent de cette calomnie, fut qu’ils s’attirèrent le mépris & l’indignation de toutes les personnes raisonnables.” I think this is the original source for this famous story, since de Thou was a contemporary of Viète.

  118 Marnix: Biographie Universelle; Biographie Nationale of the Académie Royale de Belgique.

  118 “noble, wise, gracious”: description by Paolo Rinaldi, treasurer of the Duke of Parma, quoted in Leon van der Essen, “Contribution à la biographie de Phillipe Marnix de Sainte-Aldegonde,” Analectes pour servir à l’histoire ecclèsiasticale de la Belgique, XXXIII (1911), 53-66 at 56.

  118 Marnix’s solution of Moreo letter: van der Essen, 53-66. Calendar, Foreign, January-July 1589, 278, 284, 287, mentions Marnix’s solution of a letter of Parma’s secretary indicating that the Duke intends to try to surprise Ostend or, failing that, to besiege it; the Public Record Office does not have the solution itself.

  119 Don Juan, de La Noue’s interception, Marnix: Conyers Read, Mr. Secretary Walsingham and the Policy of Queen Elizabeth (Cambridge: Harvard University Press, 1925), II, 355-358; A. J. Butler, “Some Elizabethan Cipher-Books,” Transactions of the Bibliographical Society, VI (October, 1900-March, 1902), 127-135 at 130.

  119 Don Juan’s cipher: Butler, 131; Carmona, 195-196. The solution is in Great Britain, Public Record Office, State Papers 106/1, no. 58; the original is in the Archivio General de Simanca, Estado 826, f. 168. They match perfectly.

  119 Rogers’ report: Calendar, Foreign, 1577-1578, 24.

  120 increased watchfulness at time of Armada: The report in Spencer Walpole, The Life of the Rt. Hon. Spencer Perceval (London: Hurst & Blackett,
1874), I, 4, that his ancestor, Richard Perceval, alerted England to the Armada by his solution of Spanish dispatches is not supported by any of the Calendars nor by the standard histories of the Armada.

  120 end of Don Juan’s plot: Read, II, 358-359.

  121 Walsingham-Davison letters: Calendar, Foreign, 1577-1578, 552 for March 20, 597 for April 5, 474-476 for Giraldez’ letter.

  121 Walsingham sends Phelippes cryptograms in Paris: Calendar, Foreign, 1578-1579, 37.

  121 Phelippes: Mary Queen of Scots and the Babington Plot, ed. John Hungerford Pollen (Edinburgh: Printed at the University Press for the Scottish History Society, 1922), liii-lv, cxlii.

  122 beer keg: Read, III, 10.

  122 Mary’s security: Pollen, 141-146; numerous cipher letters of Mary catalogued in Calendar, Scotland, II, at 906, 907, 933, 947, 948, 984, 999, 1001, and in many other places. Three of Mary’s cipher keys are depicted in John Holt Schooling, “Secrets in Cipher,” Pall Mall Magazine, VIII (1896), “I: From Ancient Times to Late-Elizabethan Days” (January), 119-129, at Nos. 8, 9, 12.

  122 delivered to Walsingham: Read, III, 11-13.

  122 decrypted by Phelippes: Calendar, Scotland, II, 946, 947, 948, 984, 997, 998, 999 for July 18 and 22, 1000, 1001, 1002. DNB states, at “Peter Bales,” that Bales, an English calligrapher, served as a cryptanalyst and forger in the Babington plot.

  122 Babington letter: Calendar, Scotland, II, 995.

  123 Mary’s reply: Pollen, 26; Calendar, Scotland, II, 998.

  123 forged postscript: Read, III, 43; Pollen, 45; original in Public Record Office, State Papers, 53/18, no. 55.

  123 Babington’s cipher alphabets: Calendar, Domestic, 1581-1590, 355. Reproduction using modern sorts in Alan Gordon-Smith, The Babington Plot (London: The Macmillan Company, 1936), 251.

  123 Mary’s trial and death: Agnes Strickland, Life of Mary Queen of Scots (London: George Bell & Sons, 1907), II, 422-423, 456.

  Chapter 4 ON THE ORIGIN OF A SPECIES

  This chapter depends heavily upon Dr. Charles J. Mendelsohn’s important article, “Blaise de Vigenère and the ‘Chiffre Carré,’” Proceedings of the American Philosophical Society, LXXXII (March 22, 1940), 103-129, which traces the evolution of polyalphabeticity through the various authors, and upon Luigi Sacco’s Un Primato Italiano: La Crittografia nei Secoli XV e XVI (Roma: Istituto Storico e di Cultura dell’Arma del Genio, 1958), which, though the author sometimes goes overboard in trying to prove that everything was an Italian first, is generally accurate and includes much valuable source material. The first is cited simply as “Mendelsohn,” the second as “Sacco, Primato.”