Decoding the Renaissance exhibition material

This article offers a comprehensive and descriptive list of each piece included in the Decoding the Renaissance: 500 Years of Codes and Ciphers, one of the Exhibitions at the Folger.

This exhibition was arranged into three zones: The Renaissance of Cryptography; How To Make Anything Signify Anything; and Enigmas and Machines.

The Renaissance of Cryptography (zone 1)

...a familiarity with the conditions and customs of [the sixteenth and seventeenth centuries] will bring one to the conclusion that there were, indeed, very few things in those days that did not have something to do with ciphers.

—William F. Friedman, "Saying it in Cipher" (1920)

The Birth of the Cryptographic Book (case 1)

The Renaissance was the first great age of mass communication, but it was also the period when the art of secret writing came into its own. The new science of codes and ciphers produced some of the period’s most brilliant inventions, most beautiful books, and most enduring legacies.

One of the oldest cryptographic books was written by the quintessential Renaissance Man, Leon Battista Alberti. His short text on ciphers, Opuscoli morali, first published in this 1568 collection, was written a century earlier, making it Europe’s oldest extant treatise on ciphers and earning Alberti the title of Father of Western Cryptology.

However, the first printed cryptographic book was Trithemius’ posthumous work on polygraphic (or multiple writing) systems, Polygraphiae libri sex. The title -page, which can be seen below, depicts Trithemius presenting the book to its dedicatee, Emperor Maximilian I. The monk behind him provides the keys to the locked book, whose secrets are central to the exercise of power in church and state.

Items Included

• Leon Battista Alberti. Opuscoli morali. Venice: Francesco di Franceschi, 1568. Call number: PQ4562 .A6 1568 Cage; displayed A1v (image).
• Johannes Trithemius. Polygraphiae libri sex. [Basel]: Johann Haselberg, 1518. Call number: Z103.T7 P6 1518 Cage; displayed title page (image).

The First Cryptographic Couple (case 2 and wall panel)

William Frederick Friedman (1891–1969) and Elizebeth Smith Friedman (1892–1980) are sometimes described as the nation's First Cryptographic Couple. They were introduced to the subject and to each other by the larger-than-life textile magnate George Fabyan at Riverbank, a country estate and research institute near Chicago. They joined a team providing support for Elizabeth Wells Gallup, the leading advocate of the popular idea that Francis Bacon had written Shakespeare's works and left ciphered clues throughout the 1623 First Folio and other texts. The Friedmans quickly lost faith in this theory and moved to Washington, where William ran the Signals Intelligence Service and Elizebeth worked for the Coast Guard and other agencies. But they continued their study of the Renaissance and eventually settled on Capitol Hill. Many of the books they used at Riverbank are now housed across the street in the Fabyan Collection at the Library of Congress.

The Friedmans and Shakespeare

After leaving Riverbank in 1920, the Friedmans remained in close contact with Elizabeth Wells Gallup and her fellow Baconians, collecting materials for this comprehensive critique of the Baconian authorship theory. By the late 1940s, they were giving lectures called “The Cryptologist Looks at Shakespeare.” Their original typescript (bearing that earlier title) was finished in 1954 and the revised book was published to great acclaim three years later by Cambridge University Press.

Items Included

Case 2

• LOAN courtesy of the Library of Congress. William F. Friedman. Methods for the Solutions of Ciphers. Geneva, Ill.: Riverbank Laboratories, 1917–22.
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. Exceptional Civilian Service Medal. Presented to William F. Friedman in 1944.
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. Medal for Merit. Presented to William F. Friedman in 1946.
• William F. Friedman and Elizebeth S. Friedman. The Shakespearean Ciphers Examined. Cambridge: Cambridge University Press, 1957. Not yet accessioned.
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. Photo of William F. Friedman and Elizebeth S. Friedman, ca. 1957. 310 2nd Street SE, Washington, DC.

Wall Panel

• LOAN courtesy of the Bacon cipher collection, manuscripts and Archives Division, The New York Public Library, Astor, lenox, and Tilden Foundations. William F. Friedman. Cipher Baconis Gallup. Manuscript, ca. March 1916.

Invisible Ink (case 3)

Not all secret communication depends on codes and ciphers, and one of the oldest tricks in the book was to make the message itself invisible. Using nothing more than materials found in the average kitchen—lemon juice and a candle—it is possible to make written letters disappear and reappear at will.

Items Included

• John Wilkins.. Mercury; or the secret and swift messenger. London: J. Norton for John Maynard and Timothy Wilkins, 1641. Call number: W2202; displayed p. 42–43 (image).
• Miscellaneous collection of recipes. Manuscript, ca. 1600. V.a.140; displayed fol. 14v (image).
• LOAN courtesy of the Library of Congress. H. O. Nolan. The Production and Detection of Messages in Concealed Writing and Images. Geneva, Ill.: Riverbank Laboratories, 1918.

Secretaries, Scribes, and Ciphers (case 4 and wall panel)

The cryptographic book emerged with—and through—the invention of moveable type, but people had been using cryptographic means to secure their communications for centuries before the advent of print. Diplomatic and commercial business throughout the Medieval and Early Modern periods depended heavily on handwritten codes and ciphers: official correspondence and private documents alike are peppered with mysterious symbols designed to be read only by those who had the key to the system.

Sir Francis Walsingham

Widely known and feared as England's first spymaster, Secretary of State Sir Francis Walsingham used every trick in the book to search out secrets among his enemies while keeping his own communications secure. In the letter to the right of this text, he communicates Queen Elizabeth's wishes as the King of France was on his deathbed: he advises "great circumspection" in "the matter" and urges those involved to "beware whom they trust." He is careful to put the most sensitive information into cipher. You can see one of his ciphered letters on the right.

Sir Francis Bacon

In addition to leaving secret codes in Shakespeare's plays (a theory that has proven unfounded), famous politician Sir Francis Bacon is known for providing the first English summary of the science of ciphers in his famous work Of the Advancement of Learning. In this text, he describes his own invention—"while just a teenager"—of the so-called biliteral cipher. The original 1605 edition mentions the episode only in passing; but the extended Latin edition of 1623 and its English version of 1640 explain the system in detail and show how it works in practice.

Items Included

Case 4

• Sir Francis Walsingham. Autograph letter, partly in cipher, to unknown recipient, May 26, 1574. Manuscript compilation, 17th or 18th century. Call number: V.b.264; displayed item 5 btwn. p. 434–435 (image).
• Leonhart Fuchs. De historia stirpium. Basel: Michael Isingrin, 1542. Call number: 245- 323f; displayed back endleaf 3rv (image).

Wall Panel

• George Digby, Earl of Bristol. Coded letter written for King Charles I. April 27, 1645. Call number: X.c.125; displayed p. 1 (image).

The Secret Science at a Glance (case 5)

A new field has been well and truly established when it can be divided into parts and displayed in a single view. By the end of the sixteenth century, books on cryptography could offer systematic surveys of enough techniques and technologies to fill sprawling diagrams that dazzled the eyes and boggled the mind.

Items Included

• LOAN courtesy of the Library of Congress. Gustavus Selenus [pseudonym for August II, Duke of Braunschweig-Lüneburg-Wolfenbüttel]. Cryptomenytices et cryptographiae libri IX. Lüneburg: Johann and Heinrich Stem, 1624.
• LOAN courtesy of the Library of Congress. Claude Comiers. Traité de la parole, langues, et ecritures. Brussells: Jean Leonard, 1691.

How To Make Anything Signify Anything (zone 2)

...the highest degree of cipher...is to signify anything by means of anything.... For by this art a way is opened, whereby a man may express and signify the intention of his mind, at any distance of place....

—Sir Francis Bacon on ciphers (1623)

Alphabets (case 6)

For Friedman, the pen was mightier than the sword: as he put it in his Six Lectures on Cryptology, "the greatest and the most powerful instrument or weapon ever forged or improved by man...is the weapon of literacy...and the most important invention, the one that made the weapon of literacy practical, was the invention of the alphabet." Letters themselves were cryptography's secret weapon and they had as much power to change the course of battles as bullets and bombs.

Items Included

• Giovanni Battista Palatino. Compendio del gran volume de l’arte del bene et leggiadramente scrivere tutte le sorti di lettere et caratteri. Rome: Heirs of Valerio and Luigi Dorici, 1566. Call number: Z43.A3 P3 1566 Cage; displayed F3v–F4r (image).
• Blaise de Vigenère. Traicté des chiffres, ou, Secretes manieres d’escrire. Paris: Abel L’Angelier, 1586. Call number: Z103 .V6 1586 Cage; displayed fol. 302v–fol. 303r (image).
• Giambattista della Porta. De furtivis literarum notis. London: John Wolfe, 1591. Call number: STC 20118 Copy 1; displayed p. 90–91 (image).

Stenography (case 7)

By the end of the sixteenth century, abbreviated alphabetical systems had emerged to improve the speed and secrecy of writing. "Shorthand" became widely available through popular manuals, and Samuel Pepys used it to protect his famous diary from prying eyes. Like cryptographic systems, shorthand methods replaced letters, syllables, and whole words with arbitrary symbols. This made them available, in fact, as codes and ciphers, and many authors in the field pointed to the close relationship between stenography (speedy writing) and steganography (hidden writing).

Items Included

• John Willis. The art of stenographie, teaching...the way of compendious writing. London: W. White for Cuthbert Burbie, 1602. Call number: STC 25744a; displayed A8v–B1r (image) and title page in facsimile.
• Francis Bacon. De sapientia veterum. London: Felix Kingston, 1634. Call number: STC 1129; displayed A3r additional title page (image).
• Henry Oxinden (1609–70). Manuscript miscellany, ca. 1642–70. Call number: V.b.110; displayed 2nd leaf, verso (image).
• Thomas Shelton. Tachygraphy. London: Samuel Simmons, 1674. Call number: 262551; displayed p. 1 (image).

Tables (case 8)

Alphanumeric tables are one of the first great technical inventions in the field of cryptography, and it may not be an accident that they emerged with the advent of moveable type. They took advantage of what the printing press did especially well—distributing permutations of individual letters and numbers in a square or rectangular grid—and they made the work of substituting plain-text with cipher-text easier, more accurate, and far more secure.

Items Included

• LOAN courtesy of the Library of Congress. Johannes Trithemius. Polygraphiae libri sex. [Basel]: Johann Haselberg, 1518.
• LOAN courtesy of the Library of Congress. Giovan Battista Bellaso. La cifra. Venice: 1553.
• Blaise de Vigenère. Traicté des chiffres, ou, Secretes manieres d’escrire. Paris: Abel L’Angelier, 1587. Call number: Z103 .V6 1587 Cage; displayed item 2 btwn. p. 184–185 (image).

Bacon's Biliteral Cipher (case 9)

In the course of the sixteenth century, cryptographers found ways to reduce the entire alphabet to only a few letters—and the great scientist and statesman Sir Francis Bacon devised a system using just two. In Bacon's "biliteral" (or two-letter) system, each letter of the English alphabet is represented by a different five-letter combination of A's and B's, from AAAAA for A to BABBB for Z. What made Bacon's invention so powerful is that these A's and B's could be represented by two types of anything—roman and italic type, pluses and minuses, apples and oranges, and so on. Using this system, as Friedman was fond of quoting, "it is possible to signify omnia per omnia (anything by means of anything)."

Items Included

• Francis Bacon. Of the...advancement of learning. London: Thomas Purfoot and Thomas Creede for Henrie Tomes, 1605. Call number: STC 1164 copy 1; displayed sig. 2Q1r (image).
• Francis Bacon. De dignitate & augmentis scientiarum. London: John Haviland, 1623. Call number: STC 1108; displayed p. 278–279 (image).
• Francis Bacon. Of the advancement and proficiencie of learning. Oxford: Leonard Lichfield for Robert Young and Edward Forrest, 1640. Call number: STC 1167 copy 1; displayed p. 266 (image).
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. William F. Friedman. “KNOWLEDGE IS POWER.” Aurora, Ill., ca. January 1918.

Disks and Volvelles (case 10 and wall panel)

The cipher disc may be the most iconic image in the history of cryptography. And for good reason: it puts a simple but powerful system of alphanumeric substitution into the palm of one's hand. In portable form, it was particularly well-suited for use in the field. Within the covers of the period's books, it became one of the primary applications of the new technology called the volvelle, where one circle (often featuring a pointing hand) could be turned on top of another, with each turn of the disk presenting a new cipher alphabet.

Items Included

Case 10

• Jacopo Silvestri. Opus novum. Rome: Marcello Silber, 1526. Call number: Z103 .S5 1526 Cage; displayed f. 6v (image).
• Giambattista della Porta. De furtivis literarum notis. London: John Wolfe, 1591. Call number: STC 20118a; displayed p. 72–73 (image).
• Johannes Trithemius (1462–1516). Polygraphie et universelle escriture caballistique. Paris: Jacques Kerver, 1625. Call number: Z103.T7 P6 F7 1625 Cage; displayed p. 328 (image).

Wall Panel

• Leon Battista Alberti. Opuscoli morali. Venice: Francesco di Franceschi, 1568. Call number: PQ4562 .A6 1568 Cage.

Grilles (case 11)

The popular scientist Girolamo Cardano was credited with an invention that is still in use today. In the so-called "Cardan grille" a sheet with irregular holes cut in it is laid over a blank page and the intended message is written in the spaces. The sheet is then removed and the rest of the spaces are filled in with innocent—or even misleading—text. When the recipient lays the same grid over the letter in the same position, the hidden message is revealed.

Items Included

• Girolamo Cardano. De rerum varietate. Basel: Heinrich Petri, 1557. Call number: 156- 884f; displayed title page (image).
• Giambattista della Porta. De occultis literarum notis. Montbéliard: Jacques Foillet and Lazarus Zetzner, 1593. Call number: 173- 568.1q; displayed p. 134 (image).
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. William F. Friedman and Elizebeth S. Friedman. Cryptographic Christmas Card for 1928.
• LOAN courtesy of the Massachusetts Historical Society. John Clotworthy, viscount Masereene. Autograph letter to John Winthrop, Jr., with grille. Dublin, 6 March 1634/35.

Say It with Flowers (case 12)

Friedman and his team at Riverbank were always on the lookout for ways to apply Renaissance codes to modern life. In 1920 they published an article for the Florists' Review on the famous trade slogan, "Say It With Flowers," suggesting that carefully designed bouquets could not only express general sentiments (such as love or sympathy) but also carry hidden messages. They provided an example from a seventeenth century German cryptography manual using a floral wreath and alphabetical key.

Items Included

• FACSIMILE from the Bacon cipher collection, Manuscripts and Archives Division, The New York Public Library, Astor, Lenox and Tilden Foundations. Cora Jensen [and William F. Friedman]. "‘Saying It’ in Cipher." Florists’ Review, 1920.
• LOAN courtesy of the Library of Congress. Johann Balthasar Friderici. Cryptographia. Hamburg: Georg Rebenlein, 1685.
• LOAN courtesy of the Library of Congress. Loose-leaf note from Friedman’s team at Riverbank in Johann Balthasar Friderici. Cryptographia. Hamburg: Georg Rebenlein, 1685.
• FACSIMILE from the Bacon cipher collection, Manuscripts and Archives Division, The New York Public Library, Astor, Lenox and Tilden Foundations. [Cora Jensen and William F. Friedman]. “‘Saying It’ in Cipher.” Typescript, 1920.

Music (case 13)

Music was another signifying system that could be used both to convey and to cover secret messages, with particular notes standing in for the different letters in the alphabet. The systems shown in this case made it possible for musical compositions to speak to people even when they did not contain words.

As in other examples, Friedman used the sheet music (arranged for solo mandolin) for Stephen Foster's famous song, "My Old Kentucky Home, Good Night" to show how, using Bacon's biliteral cipher, anything can be made to signify anything. By making notches in the stems of some notes and leaving others whole, he has turned the music into a sequence of a's and b's that read "Enemy advancing right / We march at daybreak."

Items Included

• FACSIMILE (adapted with message deciphered) from the Bacon cipher collection, Manuscripts and Archives Division, The New York Public Library, Astor, Lenox and Tilden Foundations. William F. Friedman. "My Old Kentucky Home, Good Night". Modified sheet music, 1916.
• John Wilkins. Mercury: or, The secret and swift messenger. London: Printed for Richard Baldwin, 1694. Call number: W2203; displayed p. 144-45 (image).
• LOAN courtesy of the Library of Congress. Johannes Balthasar Friderici. Cryptographia. Hamburg: Georg Rebenlein, 1685.
• Gustavus Selenus [pseudonym for August II, Duke of Braunschweig-Lüneburg-Wolfenbüttel]. Cryptomenytices et cryptographiae libri IX. Lüneburg: Johann and Heinrich Stem, 1623. Call number: Z103 .A9 1624 Cage; displayed p. 340–41 (image).

Steganography (case 14)

The best way to keep a secret message secure is to hide the very fact that there is a secret message at all. Alongside the development of cryptography (whereby a message is scrambled using transposition or substitution), there has been a parallel field called steganography (in which messages are kept intact but hidden within an innocent cover). We have already seen several examples of this art, including invisible ink, floral codes, and modified sheet music, and this case introduces several methods for hiding writing within pictures.

Items Included

• Johannes Balthasar Friderici. Cryptographia. Hamburg: Georg Rebenlein, 1685. Call number: 166- 900q; displayed loose leaf opp. p. 217 (image).
• LOAN courtesy of the Library of Congress. Blaise de Vigenère. Traicté des chiffres, ou, Secretes manieres d’escrire. Paris: Abel L’Angelier, 1587.
• Gustavus Selenus [pseudonym for August II, Duke of Braunschweig-Lüneburg-Wolfenbüttel]. Cryptomenytices et cryptographiae libri IX. Lüneburg: Johann and Heinrich Stem, 1624. Call number: Z103 .A9 1623 Cage; displayed p. 324–35 (image).

Enigmas and Machines (zone 3)

Bacon was, in fact, the inventor of the binary code that forms the basis of modern electronic digital computers.

—William F. Friedman, Six Lectures on Cryptology (1959–61)

Cryptography Before the Computer (case 15)

Well before the advent of digital technology, those working in the field of cryptography turned to machines to make the production and transmission of secret messages easier, faster, and more secure. Many of these devices (from Alberti's introduction of the cipher disk in the 1460s to the rotor-based SIGABA machine invented by Friedman and his colleagues in the 1930s) used single or multiple wheels to systematize the scrambling of letters. Friedman lived just long enough to see his field transformed by the introduction of computers—and to claim that "Bacon was the inventor of the binary code" on which they depend.

Items Included

• LOAN courtesy of the National Cryptologic Museum, NSA. William F. Friedman. SIGABA machine.
• FACSIMILE from the National Cryptologic Museum, NSA. US patent 6,175,625. January 16, 2001.
• Samuel Morland. A new method of cryptography. London: 1666. Call number: M2781A; displayed p. 12 (image).
• LOAN courtesy of the Preservation Partners of the Fox Valley and Kane County Forest Preserve District. Wheatstone-Plett Cipher Device. From George Fabyan’s collection at Riverbank Laboratories.

Kircher's Cryptographic Machines (case 16)

The last of the great Renaissance polymaths, the Jesuit scholar Athanasius Kircher published books on the secrets of the universe ranging from the subterranean to the super-celestial and from the ancient past to the distant future. He loved letters and numbers in equal measure, and dreamed up endless devices to help them work and play together.

Items Included

• Gaspar Schott. Schola steganographica. Nuremberg: Heirs of Johann and Wolfgang Endter, 1680. Call number: 170- 941q; displayed opp. p. 91 (image).
• Athanasius Kircher. Magnes sive De arte magnetic. Rome: Biaggio Diversin, Zenobio Masotti, and Vitale Mascardi, 1654. Call number: 166- 834f; displayed p. 290–91 (image).

The Voynich Mystery (case 17)

In 1912, a rare book dealer named Wilfrid M. Voynich acquired a cache of manuscripts from a Jesuit college near Rome. Among them was the strange codex that now bears his name, a heavily illustrated text on vellum, carefully written by an unknown author in an elaborate script or symbol system that has never been deciphered. The great Chaucerian (and World War I code-breaker) John M. Manly, one of the first scholars to examine the volume, described it as "the most mysterious manuscript in the world," and a full century after it resurfaced we still know surprisingly little about it. The cracking of the Voynich Code—if that is what it is—has long been a holy grail for students of cryptography. Research from other angles (including the history of botanical illustration and the use of computers to analyze patterns) continues to generate fresh theories that keep the manuscript in the news. We hope that this exhibition will provide new information and inspiration for the amateur and professional scholars who fall under its spell.

Items Included

• LOAN courtesy of the Beinecke Library, Yale University. The Voynich Manuscript. (ca. 1410–30).

The Friedmans and the Folger (case 18)

The Friedmans' final home was a nondescript Washington rowhouse near the corner of 2nd and C Streets SE. This location put them at the heart of the government community on Capitol Hill and gave them easy access to both the Library of Congress and the Folger Shakespeare Library. Their definitive debunking of anti-Stratfordian ciphers found an enthusiastic home here at the Folger: the couple's original manuscript won the Library's book prize and was deposited in its archive. Folders from the Friedmans’ post-retirement research are filled with the familiar green call-slips still used for Folger books, and William's 1962 article on "Shakespeare, Secret Intelligence, and Statecraft" identified him only as "Reader, Folger Shakespeare Library."

Items Included

• William F. Friedman and Elizebeth S. Friedman. The cryptologist looks at Shakespeare. Typescript, 1954. Call number: Y.d.76; displayed chapters 1–6 stacked, title page on top (image).
• William F. Friedman and Elizebeth S. Friedman. The Shakespearean Ciphers Examined. Cambridge: Cambridge University Press, 1957. Call number: PR2937 .F7 1957 Copy 2 Cage; displayed front endleaf 1r (image).
• LOAN courtesy of the George C. Marshall Foundation, Lexington, VA. Washington Post, April 3, 1955

The Friedmans and the Voynich Manucript (case 19)

After the Bacon-Shakespeare controversy, the Friedmans' favorite extracurricular project was the Voynich Manuscript. As his country's leading expert on secret writing systems, William Friedman was quickly enlisted to solve the Voynich mystery. During three different periods of sustained study (in the 1920s, 40s, and 60s), Friedman threw all available resources at the problem, including some of the earliest use of computer-assisted text analysis. But the manuscript stubbornly refused to yield its secrets to Friedman (as it had to Kircher when he was consulted in 1666), and he died with only vague theories and not a single line of deciphered text.

Items Included

• LOAN courtesy of the George C. Marshall Foundation. William F. Friedman and the Voynich Manuscript Study Group. Voynich character frequency tables, ca. 1944.
• LOAN courtesy of the George C. Marshall Foundation. William F. Friedman and the Voynich Manuscript Study Group. Agreed alphabet for transcription of Voynich characters. June 13, 1944
• LOAN courtesy of the George C. Marshall Foundation. Lexington, VA. RCA Computer run of characters from the Voynich Manuscript, ca. 1962

Puzzling Pages (case 20)

People who have the qualities of mind needed to make and break codes often delight in puzzles. There has long been a close affinity between cryptanalysts and crossword puzzles, and Friedman was one of many who got their first introduction to the field through Edgar Allan Poe—who wrote a regular newspaper column in which he solved ciphers sent in to him by readers and whose famous story "The Gold Bug" played a major role in popularizing cryptograms.

Items Included

• Athanasius Kircher. Polygraphia nova et universalis ex combinatoria arte detecta. Rome: Lazzari Varese, 1663. Call number: Folio P361 .K5 1663 Cage; displayed p. 23 (image).
• Henry Clay Folger and Emily C. J. Folger. Solution to "Shakespearean Enigma" crossword. New York Herald Tribune, March 15, 1925. Call number: Y.d.1009; displayed 2b (image).
• LOAN courtesy of the George C. Marshall Foundation, William F. Friedman and Elizebeth S. Friedman. Cryptographic dinner menu, May 15, 1929.