Tag Archives: medieval ciphers

An Enciphered Herbal

buy modafinil in usa 22 September 2020

Guyong A few years ago I noticed something was going on with the plant names in Codex LJS 419, but I was busy with other research, so I bookmarked it for future reference. In March 2020, with most of the world in quarantine, I finally had a few minutes to leaf through the scans and realized, when I saw the peony plant, that the labels had been lightly enciphered.

A Plant Book that Spanned a Century

According to the U. Penn Schoenberg Collection Subject Details, the LJS 419 Erbario was begun in the first half of the 15th century with a number of later additions. The drawings are quite good for 15th century. Some are stylized, but most are recognizable.

UPenn Schoenberg Collection LJS 419 is a bit of a pastiche. The drawings are in at least three different styles, and the ones on the recto (the original drawings) are frequently smaller than the ones they face.

There are labels by most of the drawings, and text under some of the images in handwriting that was common to the 16th century. Thus, the text may have been added as much as a century after the drawings.

I noticed that some of the labels are incorrect. The plant below is clearly not Calendula, a plant that has had the same name for centuries. It is recognizable as Senecio, probably Senecio vulgaris:

LJS 419 drawing incorrectly labeled as Calendula.

The labels for Pulmonaria (65v) and Salvia (65r) don’t match the plant drawings either, but if you swap the labels, then they match (a detail that the Shoenberg commentator didn’t note in the annotations for each plant).

Most of the labels appear to be correct, however, and they are interesting because some of them are in cipher…

The Garbled Plant Labels

Some of the plant names are readable. Others are oddly spelled and overwritten, like this one:

LJS 419 Latucha changed plant label

The word “Latuca” is somewhat mangled. Adding a stem to each “a” makes it Lbtucb. The next word, “agrestis” has a stem through the “e” to make it “f”, and the “i” is “l”.

I wasn’t sure what was happening until I saw an odd label next to a plant that was easy to identify. That’s when I realized this was a simple cipher with some of the vowels changed.

Here is the label. It reads pepnla:

I could see this was a Peony plant not a “Pepnla” plant which, in turn, made it clear that this was a partial substitution cipher. It is sometimes called the monk’s cipher and I can see why. I have often seen it in manuscripts with ecclesiastical content, like sermons.

Notice how the “o” is “p” (I saw the same substitution in some of the earlier plant labels), and the “i” is changed to “l” (ell). That was the clue. It’s a common and simple vowel-substitution cipher that is quite easy to read once you get used to the fact that consonants are used for vowels:

  • The “o” is changed to “p” because it is a vowel and “p” is the closest consonant following “o”.
  • The “i” has been changed to “l” because it is the closest consonant following “i”. They didn’t have “j” in the Middle Ages (what looks like “j” was usually an embellished “i”) and many languages did not have “k”, so “l” (ell) would be the closest consonant following “i”.

I’m not sure why they left the first “e” and last “a” as vowels rather than substituting all the vowels. Either it was an oversight, or perhaps they thought Pepnla was enough to obscure the name.

Here’s another example that reveals the order in which things were done for this label but apparently not for all the labels:

Underneath, it looks like Spftlnb, which is a little more difficult to read without decoding it first because it is both abbreviated and enciphered. Someone wrote over it with darker ink, to create S~pe’tina, which is an abbreviation for Serpentina. It uses the same system as the others, of selecting the next-closest consonant to replace the vowel.

Note how the “u” letters in the next two words were written as “x”, which is to be expected for a consonant following “u”. Many languages did not have the letter “w”, and “u” and “v” were roughly equivalent, so “x” is a natural substitute.

Sometimes plaintext is written over the ciphertext. Sometimes it’s the other way around. Perhaps there were three hands involved, one turning it into ciphertext, someone else converting it back.

Now that it was clear that a consistent system was used, it became straightforward to decipher the last word cpstb which was not overwritten. This can be deciphered as “costa”. Costa is a medicinal plant that was common in medieval herbals.

A plant drawing that clearly depicts Asphodel also has an altered label. It looks like this:

Here the ciphered text is Afpdklk, and we can see that the “o” was written as “p” (consistent with the previous examples). The two “i” characters in Afodili (one of the common spellings at the time) were written as “k”.

So the writer apparently did know the letter “k” (“k” was not used in every language but sometimes it was used in loanwords). The phrase following the name “herba di Sbtxrnp” is only partly enciphered. It decrypts to herba di Saturna.

The next label reads Bftpnlchb, which decrypts to Betonicha, another very common plant in medieval herbals:

The next one might have been harder to read without the picture, since it is both abbreviated and enciphered, but it includes a good drawing of the plant:

The word was overwritten as Tprmftlla, which decodes to Torme’tila, with the macron standing for the missing “n” in Tormentila.

The next one reads dltamp bla’chp, so the “a” was left in its normal state. The plaintext is ditamo biancho. Note the humanist-style “h”, which has a short stem that doesn’t quite reach the baseline. This, in addition to the overall style, is one of the palaeographic clues that the labels were probably added in the later 15th century or, more likely, the 16th century:

Male and Female Plants

The following label puzzled me for a moment. Since pepnkb isn’t a plant name, it has to be the enciphered word peonia. But it doesn’t look as much like a peony as the other drawing already mentioned. It is more upright, and drawn without the seeds. Then I remembered that some medieval manuscripts included both “male” and “female” (mascula, femina) versions of peony, just as they did for Mandrake and a few other plants. Since there is a very recognizable peony drawing on the verso, I’m guessing that it represents the female and the recto represents the male plant:

The next label reads Mprssus dkbbpli, which translates to Morssus diaboli (devil’s bite), a common name for several species of Scabious.

But the drawing is not a Scabious plant. Scabious has pufflike flowers, not bell-shaped flowers. The flower in the drawing is like Campanula, but the hairy stalk and parsley-like leaves are not, so it is probably Pulsatilla, the Pasque flower, rather than Scabious. Most Pulsatilla flowers do not dangle as much as this, they tend to spread their petals, like anemones, but they do sometimes hang, depending on the species. Taken together with the flower shape, leaves, and fibrous base, it’s probably Pulsatilla:

The next label is lxnbrkb, which is described as follows in the Schoenberg annotations for this manuscript:

66: ‘Lenbrkb’ – a puzzle, though the same word is used for a different plant on 71r

It’s really not that puzzling. This decrypts quite easily as “lunaria” by using vowel-for-consonant substitution:

Lunaria, enciphered plant label in LJS 419.

Compared to ciphers of today, or even of 200 years ago, this is easy to read. You don’t even have to make a chart, you just have to learn the letter that follows each vowel and you can read it as though it were normal text.

Other Interesting Details

A few of the drawings are unpainted and include color annotations, a detail that may also exist in the Voynich Mansucript:

LJS 419 unpainted plant drawings with color annotations

Why someone chose such light encipherment for plant names (and only enciphered a few of them) is difficult to understand. Maybe they did it for fun. Maybe they were planning something similar for the rest of the text but never completed the task. What it tells us, however, is that even in the 16th century, these very simple ciphers were still in use, and if you combine them with abbreviations, they can sometimes be a bit more challenging to figure out if there are no drawings to make the meaning clear.

Summary

I had planned to post this blog in April, but simply forgot about it. Then today, I saw the paper of Alisa Gladyseva on Researchgate.net where she describes the peony name in this manuscript as an example of a “corrupted” plant name.

I was quite stunned that someone who writes a paper on the history of cryptography and who claims to have decoded the VMS did not recognize the monk’s cipher (which is simple and only involves partial substitution of vowels) and so I decided to post this blog so the VMS community can compare her interpretation with what is really happening in LJS 419. Here is what Gladyseva wrote in her paper:

Obviously, some names of 13 plants [in MS Aldini 211] seem to be corruptions of known names e.g. ‘Antolla’ for ‘Anthyllis’, ‘Ariola’ for ‘Oriola’. 23 plant names are strongly corrupted for e.g. ‘Metries’ for ‘Myrtus’, ‘Rigogola’ for ‘Galega’….

Manuscript Number is ‘ljs419’ Italy, of XV century is a typical of the medieval Apuleius herbal. But it has corrupted botanical names of plant on 71r folia. As well as the name of plant ‘Pepeko’ 24r, that is probably is one of the species of peony in real. | P E O N I O |. In reason, on the next folia there is another kind of peony: 24v: ‘Peonia’. –Gladyseva, Jan 2020

So, Gladyseva includes a paragraph on corrupted plant names and then cites LJS 419 as an example of corrupted plant names, but it is not! It is an example of a common and very simple medieval substitution cipher, as can be seen by the decryption examples I posted above.

Gladyseva has been claiming for some time that she has deciphered the VMS, but never shows any concrete examples of her method. How could a researcher who claims to have deciphered the Voynich Manuscript in a paper that describes the history of cryptography have missed something so simple and obvious as the monk’s cipher?

I think it’s time for her to reveal her method so the rest of the research community can see if there is sufficient evidence to support her claims.

J.K. Petersen

© Copyright September 2020, J.K. Petersen, All Rights Reserved

Fontana’s Cipher Design

20 July 2020

Giovanni Fontana’s circle-line cipher is designed to be mnemonic without being too obvious about what the symbols represent. I’ve noticed this characteristic in several medieval and Renaissance ciphers, including the cipher of Hildegard von Bingen.

The Fontana Cipher

Johannes de Fontana (c. 1395–c. 1455) was a physician and engineer educated at Padua in the early 15th century. Fontana was interested in clockworks, and created entertaining devices, like clockwork-based skeletons, to showcase his engineering talent. But he is best known for Bellicorum instrumentorum (BSB Cod.icon. 242), an illustrated book of devices for warfare and sieges created in Venice in the 1420s.

The introductory page of Bellicorum instrumentorum includes a paragraph of plaintext followed by ciphertext. Here is some of the plaintext:

Fontana plaintext from Bellicorum instrumentorum

Lombardy and northern Italy were part of the Holy Roman Empire in the 15th century. Venice managed to keep its independence through much of this period but was, of course, influenced by surrounding city-states. Italian culture is more evident in Fontana’s script than germanic culture. The final-ess (long-ess) is one of the clues. This was fairly common in Italy and much less so in Germany and France, where they preferred a B-shape or sigma-shape for final-ess. There is also a distinct lack of loops (a characteristic that was adapted by humanists all over Europe in the late 15th century and 16th century but was uncommon in Germany and France in the 15th century).

The “a” without a crossbar is another letter to note. This is a more traditional form of “a” that was uncommon in 15th-century Germany and France but used from time-to-time in Greek texts, early-medieval texts, and some of the Italian scripts. The raised “q” is unusual and Fontana did not always write it this way in earlier texts.

Below the plaintext is a block of ciphertext:

Fontana ciphertext

Most of the folios include a drawing, a block of plaintext, and a block of ciphertext:

Fontana Bellicorum page layout

The drawings are not professional-level, but they are reasonably clear and instructive, like the VMS drawings. The main difference is that the Fontana drawings show a better understanding of three-dimensional mechanics than the VMS (the weakness in three-dimensional thinking is especially apparent in the muddled way VMS human joints are drawn).

The Fontana Cipher Characters

Someone has added the following alphabet to a foreleaf of Bellicorum instrumentorum, but you don’t need it to decode this cipher. Fontana designed his cipher to be easy to read, thus making it easy to decipher:

Fontana cipher alphabet on the foreleaf of Bellicorum instrumentorum

Before I break down the alphabet, I’d like to point out another book by Fontana, called Secretum de thesauro experimentorum ymaginationis hominum (BNF NAL 635, c. 1430). Like Bellicorum, this includes a significant amount of ciphertext and some interesting rotary text mechanisms:

Giovanni Fontana ciphertext from Secretum de thesauro axperimentorum
Fontana alphabet wheel
Fontana Secretum Rotulus

The manuscript describes various kinds of memory and mnemonic devices and Fontana’s interest in these subjects sheds some light on the design of his cipher.

The Rationale Behind the Fontana Cipher

Start with a basic concept—circles and tickmarks.

  1. Line up the vowels with a circle to represent each one.
  2. Starting with the outermost circles, add tickmarks facing west and east.
  3. Now go to the “e” and “o” circles and add tickmarks facing north and south.
  4. There are 5 vowels and only 4 cardinal directions, so leave the “i” as it is but you can imagine the circle being squished in from the sides until it resembles “i” (this will also help with remembering another letter). You can draw it round, you just have to think of it squished to remember it’s the letter “i”.

Now you have 5 vowels.

Fontana cipher vowel mnemonic system

How can circles and tickmarks be used to create consonants while still keeping the cipher reasonably mnemonic? Quite often in medieval ciphers (including the cipher of Hildegard von Bingen), some of the cipher shapes are formed by mirroring.

In Hildegard’s lingua ignota, the r, b, and h are drawn almost in the normal way except an extra tickmark has been added to b and h. The letter “u” is normal for her time period, as well (the double-cee sometimes also stands for “a” in early-medieval texts). But the “d” and “p” have been mirrored in the horizontal direction and “y” is mirrored in the vertical direction:

Fontana used mirroring, as well, in a more methodical way than Hildegard.

  1. Take the letters b, d, p, and q (which are morphologically similar) and mirror them in the horizontal direction.
  2. Extend the straight strokes (otherwise the identity of the letter is a little too obvious).
  3. Add a tickmark pointing in the direction the letter would normally face, and further place it up for b and d, down for p and q (the normal direction for the ascender or descender).

Creating a mnemonic “s” is easy. Close the loops. It can be written both vertical and horizontal and is still easy to remember because it is the only character with two loops. The “t” is also easy. Remember that the “i” is a simple loop and imagine it squished. Now add a crossbar on top and you have a mnemonic “t”. In fact, some of the other consonants, like y and z also substitute the circle for a stroke.

After a while, you run out of the simple shapes, so Fontana used a different way to remember h, k, m, and n. Instead of mirroring, these letters are based on strokes. The letter “h” has two main strokes, so the cipher character has a circle with two strokes up and right. The “k” also has two strokes up and right, but the letter “k” has a third angled stroke, so this is added as well:

The letters “m” and “n” work the same way. The “m” has three strokes, the “n” has two, and this is how many are attached to the circle. The direction doesn’t even matter since h and k are at right angles, with one stroke mimicking the ascender. The m and n are parallel and thus easy to distinguish from h and k.

This is quite clever. It might be worth repeating… since the parallel and perpendicular lines are distinguishable by their angle, the direction doesn’t matter and Fontana does sometimes vary the direction. This concept could be used to design a new cipher that was more difficult to read, by varying shapes so they appear to be different when, in fact, they are not. That was not Fontana’s intention with this cipher, but it presents some intriguing possibilities.

That’s most of the alphabet. The “f” is mirrored in the vertical direction and since all the letters are circles and lines, a circle is added in the crook.

You might think that Fontana used a Venus symbol, but the resemblance is coincidental. If you move the ascender of the “g” to the center and add a tick, in the same pattern as the other characters, it is recognizable as a “g”. If you make a mouth shape with your left hand and imagine you are holding a marble, it creates the ciphershape “c”.

At the end of the alphabet, we have x, y and z. Draw a cross for x and put a circle in the crook. This is another construction in which direction doesn’t matter. As long as it begins with a cross, you could recognize it no matter which direction it’s turned (I’m going to keep emphasizing this, since a cipher based on these concepts has flexibility that linguistic alphabets don’t). Since crosses are often substituted for X, this is easy to remember.

Draw an angled line for y and z (both of which have angled strokes) and put a circle on the side that needs a missing stroke and use an extra connector to distinguish z from y.

Postscript 22 July 2020: I forgot to insert this diagram when I originally posted the blog. It illustrates how a stroke from each of these letters is expanded into a circle to create the corresponding cipher character.

There are only two letters that are difficult to categorize, and that is “l” and “r”. Maybe readers can figure out the motivation behind them.

Overall, the cipher is systematic and mnemonic.

Summary

Many ciphers are intended to conceal and the desire for hard-to-crack systems increased in the 15th century. More sophisticated ciphers (by medieval standards) included one-to-many relationships, revolving keys, nulls, and glossaries. Numeric ciphers became more prevalent as well. Soon a whole science of cryptology began to develop, one that is still evolving today. One-to-one substitution was basically obsolete by the 16th century.

So why was Fontana’s cipher so easy to decipher and to learn? I think that’s exactly what he intended. He had an interest in mnemonic systems in general and his cipher demonstrates several memory-jogging techniques that enabled him to write entire tracts in cipher characters.

Now you can read Fontana’s books. Just remember that “u” and “v” were interchangeable in the Middle Ages. Here’s a simple word to get you started.

Also… I noticed, as I was paging through Secretum, that Fontana broke words across lines without line-continuation marks and that he did use some light abbreviation, but he included abbreviation marks, so it’s not particularly troublesome.

J.K. Petersen

© Copyright July 2020 J.K. Petersen, All Rights Reserved