Though Professor David A. King is best known, academically speaking, for his detailed study of astrolabes, I first ran across him via his epic (2001) tome “The Ciphers of the Monks” (summarised here): there, what happened was that one particular 14th century astrolabe from Picardy had some markings in an unusual number system first devised by Cistercian monks, and – like the proper devotee of historical arcana he assuredly is – King began collecting all the occurrences of that system he could find, which culminated in his book on the subject. There’s also a nice paper here on how the same number system was also used for tallying / gauging wines in the late Middle Ages.

All of which provides a suitable introduction to King’s most recent excursus beyond mainstream astrolabe history, because for this too the herald for his ‘call to adventure’ was an astrolabe with unusual markings on it (this time, an angel and an apparently acrostic dedication). But this second astrolabe also had a remarkable provenance – that Renaissance king of astronomers Regiomontanus had constructed it and presented it to his patron Cardinal Bessarion. Once again, David King set out to try to uncover the meaning of an astrolabe’s curious engravings – but his research journey carried him onwards to the artist Piero Della Francesca, right at the heart of the Renaissance project…

The angel part of the astrolabe engraving looks straightforward enough (note the parallel hatching on the top wing-edges, the trendy crosshatching in the background, the mid-Quattrocento “^” for “7” in the 60/70/80/90 sequences, and the early-Quattrocento ‘4’ shape at the bottom):-

Similarly, the dedication looks straightforward enough too at first glance (note the looped early-Quattrocento ‘4’ in 1462):-

ANNIS OPVS :~ 1462

King translates this as: “Under the protection of the divine Bessarion, said to come from the cardo, I arise as the work of Ioannes in Rome in 1462“. But the clever part, King believes, is that Regiomontanus’s slightly clunky Latin manages to cleverly conceal a number of additional messages to his new patron Bessarion:-

Here eight hidden vertical axes of an acrostic contain all sorts of hidden messages that would have especially pleased the Cardinal once he had figured them out: references to himself and his rank, to Regiomontanus, and to an old Byzantine astrolabe that he had shown to the young German. The angel is Bessarion, but not the Cardinal. There are several plays on the Latin word cardo, meaning “hinge, axis or pole”. In brief, two astrolabes come together in one, two poems, two languages, two Bessarions, two men who used the name Ioannes, two places, Rome and Constantinople, all come together in one.

Ummm… eh? It’s just a dedication, isn’t it? When I first looked at it, all I really noticed was the word “DEI” vertically hidden at the end: but Professor King thinks that the wobbly spacing and stretched letters indicates that there is much, much more going on here. However, it has to be said that after it was auctioned by Christies in 1989, precisely the same evidence was used to argue that it was “suspicious”, and that it even might be a “19th-century fake”: so be aware that we are now entering the kind of is-it-a-cipher/is-it-a-hoax territory that should be eerily familiar to Cipher Mysteries readers…

The other thing you need to know is that Bessarion also owned a spectacular Byzantine astrolabe dated 1062, which also had “:~” on one of its engraved bands of text: King agrees with Berthold Holzschuh that the two astrolabes are connected in some way, and that perhaps part of the reason for Regiomontanus’ presenting it to Bessarion in 1462 was to mark the 400th anniversary of the making of the magnificent Byzantine astrolabe.

So, let’s take a deep breath and dive deep into King and Holzschuh’s acrostic world, to see if his theories hold water (or if they sink like a stone)…

Firstly, Holzschuh suspects that the primary secret message held here emerges if you reorder the words to mirror the start of the Greek text on the Byzantine astrolabe:.

ROMAE 1462

…which (because the Latin word ‘cardo’ means hinge or axis) he translates as “Under the protection of Bessarion, I arise in Rome in 1462 as a work of Ioannes explaining the rotation of the universe“. He also notes that the angel’s fingers “point to 4 and 8 hours on the horizontal scale of the markings below it, suggesting we should look for eight items in the four lines of the epigram“. The eight vertically hidden messages he highlights look like this:-

(Note that this is adapted from p.12 of David King’s Regiomontanus theory webpage, but that the DEI ESIO (ESIO TROT‘, surely?) acrostic ringed in red was mislabelled VIII).

Now, I have to say that I really am particularly impressed with the acrostics marked I (SVB CD ANNIS) and VIII (1062 / 1462), in that these not only tie in neatly with the “:~” on Bessarion’s 400-yearold Byzantine astrolabe, but also nicely explain (a) the curious starting position of “SVB” on the top line and (b) why IOANNIS is split over two lines. However, sorry to be a dreadful cipher party pooper but I don’t actually buy into a single one of the other acrostics suggested, nor into any of the hundreds of tenuously complex patron saint / birthday / symbolism / IO / 1407 / golden section etc arguments that are used to support them. No, not even the angels’ fingers.

To my eyes, the astrolabe’s acrostic angle does tell a hidden story: that Regiomontanus presented this to his patron in 1462 with a silent nod to the 400th anniversary of Bessarion’s Byzantine astrolabe. Perhaps there’s even “DEI” hidden on the right (though this seems way too prosaic and straightforward for the needs of King’s complicated exegesis). However, I honestly don’t see any evidence of anything else hidden in the message that is beyond pure chance, i.e. that you could not also extract from just about any other Latin inscription of comparable size and date.

Hence, I just can’t make the giant leap over to the second plank of King’s narrative, which connects Bessarion’s patronage of Regiomontanus (as expressed in the 1462 astrolabe) to Piero Della Francesca’s epic painting “The Flagellation of Christ“, which Martin Kemp (1997) rightly described as “sumptuously planned”. This single work has caused more art history ink to be spilled in vain than perhaps any other painting (yes, even more than the Mona Lisa): King tabulates (pp.23-24) over forty subtly nuanced theories about who the various characters represent, before adding Berthold Holzschuh’s (2005) theory to the list – that the bearded man at the back being whipped is Cardinal Bessarion, and that the man in red at the left of the foreground group is Regiomontanus.

Nope, sorry – this theory doesn’t work for me either. There’s maths and geometry aplenty in Piero’s work, sure, but I completely fail to see how it links to Bessarion and Regiomontanus on any level. Perhaps my idea of what constitutes evidence is just too limited, or maybe I’m just too stupid to grasp how these two objects do really form part of a vast Renaissance patronage fugue. 🙁

If, however, you’re still intrigued by all this, there’s a nice set of slides on King and Holzschuh’s theory here: and a 2007 book by David King on the subject, with the snappy title Astrolabes and Angels, Epigrams and Enigmas – From Regiomontanus’ Acrostic for Cardinal Bessarion to Piero della Francesca’s “Flagellation of Christ” (Stuttgart: Franz Steiner) that you can buy on Amazon, though be warned that even a second-hand copy is a hefty £120 (yes, really!) Enjoy!

For a decade, I’ve wondered whether any of the Voynich Manuscript’s circular drawings depict astronomical instruments – for before satnav there was celnav (“celestial navigation”). Here’s a brief guide to three key instrument types from the VMs’ timeframe, and my current thoughts on the enigmatic circular diagram on f57v…

* * * * * * *

A key navigational problem of the 15th century was determining your latitude. Though many different instruments (such as the quadrant, the cross staff, and the back staff) came to be used to do this around this time, I’m restricting my observations here to the three purely circular ones – the astrolabe, the mariner’s astrolabe, and the nocturnal.

(1) Though astrolabes were originally used for determining the positions of planets and stars, people realised that they could also be used for telling the time (if you knew your latitude), or for working out your latitude (if you knew what time of day it was). Astrolabes were constructed from a complex (but well-known and well-documented) set of multilayered rotating components:-

  • A backplate (the mater) whose edge (the limb) is marked round with 24 hours or 360 degrees
  • A large circular central recess (the matrix, or womb) in the mater, into which you insert…
  • A disk (the tympan) containing a stereographically projected map of the sky for a particular latitude
  • On top of the tympan goes a rotating spidery net-like thing (the rete) containing easily recognizable stars;
  • On top of the rete goes a long rotating rule (the rule)
  • On the back goes a second rotating rule-like thing with two sighting holes / marks (the alidade)

If you haven’t seen an astrolabe dissected, there’s a nice annotated diagram on the Whipple Museum website.

My understanding is that most medieval European astrolabes were inaccurate because they were made of wood, though this improved when they started to be made of metal (an innovation which I understand mainly began in the 15th century). Yet even with well made astrolabes to hand, using them can be a bit tricky, particularly when you are at sea: and they’re not very convenient to use at night either.

(2) So, step forward the mariner’s astrolabe (or sea astrolabe or ring). Though this was little more than a cut-down version of the astrolabe, its key design feature was that it was built to be particularly heavy (and so was much more stable at sea). In contrast to the thousands of astrolabes out there, only 21 mariner’s astrolabes are known: the earliest description of one is from 1551, while historians suspect they came into use in the late 15th century.

Really, this was little more than a superheavy astrolabe limb hanging from a ring and with an alidade on the front: but it did the job, so all credit to its inventor… whoever that may be. The Wikipedia mariner’s astrolabe page notes that it might possibly have been Martin Behaim (1459-1507), but because it seems he was adept at relabeling other people’s discoveries and inventions as his own, probably the most we can pragmatically say is that the idea for the mariner’s astrolabe was ‘in the air’ in the mid-to-late 15th century.

(3) Solving the astrolabe’s other major shortcoming, the nocturnal (or nocturlabe, nocturlabium, or horologium noctis) was specifically designed to be used at night. A 2003 paper notes that the first evidence of nocturlabes was not a textual mention in 1524 (as was long thought), but rather a series of actual devices made by Falcono of Bergamo and dating from 1504 to 1507 (who also made astrolabes, such as this one from the British Museum). For a nice picture, the National Maritime Museum has a 17th century nocturnal here (D9091).

As far as construction goes, a nocturnal consisted of: a rotating outer ring marked both with the months of the year and with the 24-hour time; a hole in the middle of the central pivot that you could see through; and a second rotating ring with one, two, or three pointers. Once you had rotated the outer ring to closely match that day’s date, you would hold your nocturnal at arm’s length, line Polaris up through the central hole, and then align the second rotating ring so that its pointers pointed at some well-known stars (normally Shedar [α Cassiopeia], Dubhe [α Ursa Major], and Kochab [ß Ursa Minor]): there’s some nice discussion here on why these were chosen.) Once you had done all that, you would find (as if by high-tech magic) that the major pointer on the second ring would be pointing to the current time of day marked on the first ring. (Well… pretty much, anyway.)

Here’s a simplified look at the night sky, highlighting the four key stars referred to on a typical nocturnal:-

Incidentally, an open history of science question is whether Columbus had a nocturnal on his well-equipped voyages of discovery. This well-informed page seems to imply that he did, and that it was used to determine midnight – the ship’s boy would then turn over an “ampoleta” (a little sand-glass that would take half-an-hour to empty) to start counting out the daily cycle of shifts. Unfortunately, it turns out that Columbus didn’t properly understand how to use his various astronomical instruments, and that he faked a number of his latitude records. Oh well!

To summarize: though the astrolabe had been used and developed since antiquity, there was little about it that was secret circa 1450. However, this was the moment in history when people were starting to apply their formidably Burckhardtian Renaissance ingenuity to get around the limitations of the traditional astrolabe, by adapting the basic design for use at sea and at night. Yet for both the mariner’s astrolabe and the nocturnal, the documentary evidence is silent on who made them first.

* * * * * * *

What, then, of the Voynich Manuscript?

I have been trying to get under the skin of the ringed diagram on f57v for many years: even by the VMs’ consistently high level of (well) anomalousness, this page has numerous anomalies on display that seem to promise a way in for the determined Voynich researcher:-

  • Its drawings most closely matches the circular astronomical drawings in Q9 (‘Quire #9‘), yet its bifolio is bound in the middle of the herbal Q8
  • It has a curious piece of marginalia at the bottom right
  • There’s a spare ‘overflow’ word at the top left [marked green below]
  • The second ring comprises essentially the same 17-character sequence repeated four times
  • Each 17-character sequence contains an over-ornate anomalous “gallows” character [marked red below]
  • The 17-character sequence contains a number of low-instance-count letter-shapes
  • The fourth ring contains another long sequence of single characters [marked blue below]
  • It has four strange ‘personifications’ drawn around its centre (seasons? winds? directional spirits?)
  • It is far from clear what the four personifications are depicting, let alone representing
  • Finally, it has a ‘sol’-like dotted sun at the centre

I therefore think that any proper account of f57v should therefore not only offer a high-level explanation of its intent and content, but also a low-level explanation of these anomalous features. The problem is that any reasoning chain to cover this much ground will almost inevitably require a mix of codicology, palaeography, history, astronomy, and historical cryptography… so bear with me while I build this up one step at a time.

First up is codicology: Glen Claston and I agree that f57v was probably the very first page of the astronomical section Q9 – by this, we mean that the two bifolios currently forming Q8 have ended up bound upside-down. So, even though the current folio order is f57-f58-(missing pages)-f65-f66, the original folio order ran f65-f66-(missing)-f57-f58. The page immediately preceding f57v (i.e. f57r) has a herbal picture on it, which is why Glen and I are pretty sure that f57v formed the first page of the astronomical section: while both sides of f58 have starred paragraphs (and no herbal drawings), which also makes it seem misplaced in the herbal section.

A second clue that this is the case is the marginalia mark at the bottom: I think this is a scrawly “ij” with a bar above it (i.e. secundum), indicating the start of Book II (i.e. where Book I would have been the herbal) – this probably isn’t a quire mark because it doesn’t appear on the end folio of a quire. And a third clue is that the page we believe originally facing f57v (i.e. f58r) has an inserted blank block at the start of the first paragraph, which I suspect is a lacuna [highlighted blue below] deliberately left empty to remind the encipherer that the unenciphered version of this page began with an ornamented capital.

As for the odd word at the top left, the odds are that this is no more than an overflow from the outermost text ring: a similar overflow word appears in one of the necromantic magic circles famously described by Richard Kieckhefer as I described in “The Curse” (though of course this doesn’t prove that this page depicts a magic circle).

I think codicology can also help us to understand the mysterious 17-glyph repeating sequence, a pattern that has inspired many a high-concept numerological riff over the years: for if you look carefully at the four over-ornate gallows, you might notice something a bit unexpected…

Even though I’d prefer to be making this judgment on the basis of better scans (which seem unlikely to be arriving any time soon, unfortunately), I’m pretty sure that what we’re seeing here is a pair of characters which have been joined together to resemble a non-existent gallows. I’d even go so far as to say that I think that the decision to make this change was probably made while the author was still writing the page: from which I infer that 18 x 4 would have been too obvious, but 17 x 4 was obscure.

If you accept that this is right, then this changes the number patterns completely, because whereas 4 x 17 = 68 doesn’t really have much numerical (as opposed to numerological) significance, 4 x 18 = 72 does – for you see, 72 x 5° = 360°. And if we are looking at some kind of 360° division of the circle, then all of a sudden this page becomes a strong candidate for being some kind of enciphered or steganographically concealed astronomical instrument, because division into 360° has been a conceptual cornerstone of Western astronomical computing for millennia.

For several years, I therefore wondered if f57v might be depicting an astrolabe: but I have to say that the comparison never really gained any traction, however hard I tried. However… the question now comes round as to whether f57v’s circular drawing might instead depict a mariner’s astrolabe or a nocturnal.

That this might be a mariner’s astrolabe is perfectly plausible. The ‘overflow word’ might denote a ring, the second 360° ring could be the scale round the edge, and the four people in the middle could simply be decorative “fillers” for the four holes normally placed in the middle.

Comparing f57v with a nocturnal, however, is particularly interesting. The obvious thing to hide in the central design would be depictions or denotations of the constellations and the sighting stars so crucial to the operations. Given that there are plenty of different strength lines and curious shapes in the four characters to be found there, let’s take a closer look…

Now, the four elements we’d expect to see in a description of a nocturnal are Cassiopeia, Ursa Major, Ursa, Minor and Polaris: and I suspect that this is what we have here. Look again at the woman’s face on the left, and I wonder whether her name has been quite literally written across her face:-

As for the top and bottom characters here on this page, they have long puzzled Voynich researchers – why are they so wildly hairy and apparently facing away? What kind of a person is being shown here? Perhaps the answer is simply that these represent not people but bears, specifically the Great Bear (Ursa Major) at the top and the Smaller Bear (Ursa Minor) at the bottom.

The final character of the four would represent Polaris (short for stella polaris), which in the 16th Century (?) came to be called ‘Cynosura’ (the Greek mountain nymph who nursed Zeus in Crete). I have to say that I don’t really know what is going on here – perhaps other people better versed in astronomical history or mythology might be able to tell me why this person should be carrying a ring or an egg (?), and what the character’s curious strong lines (nose and top of upper arm) might be denoting.

Yet perhaps the biggest clincher of all, though, is the ‘sol’-like shape right at the centre of f57v. We might be able to discount the possibility that this represents the astrologers’ glyph for the sun, because this only came into use around 1480 (as I recall). For in the context of a drawing of a circular astronomical instrument, is this not – almost unmistakeably – a depiction of Polaris (the dot) as viewed through a hole in the pivot (the circle)?

As always, the evidence is far from complete so you’ll have to make up your own mind on this. But it’s an interesting chain of reasoning, hmmm?

Spookily, the kind of analogue computing embedded in nocturnals has a thoroughly modern equivalent. Polaris does not sit precisely on the Earth’s pole but rather rotates around it very slightly, and so requires a correction in order to be used as a reference for true North (on a ship, say). Hence a spreadsheet can be constructed to make this fine adjustment – essentially, this is a nocturnal simplified and adapted to yield the north correction required. Some good ideas can remain useful for hundreds of years!

Following on from Philip Neal’s translations, I wondered to myself: what might be lurking in Jesuit archives (specifically to do with Jacobus de Tepenecz / Sinapius)? And so I thought I’d have a quick snoop…

For Jesuitica in general, has a useful list of Jesuit archives, of which the big three are (1) Georgetown University’s numerous Special Collections [Maryland District of Columbia]; (2) Loyola University Archives [Chicago]; and (3) the Maurits Sabbe Library at the Katholieke Universiteit Leuven [Belgium]. Incidentally, Georgetown has a very cool favicon, hats off to their web designer. 🙂

A slightly wider web-trawl yields more resources: an EBIB article on a giant Jesuit library in Poland (with an online catalogue), and the Library Sankt Georgen in Frankfurt am Main. Doubtless there are many more to be found, but that is at least a starting point.

As an aside, the Society of Jesus was born at the height of the Republic of Letters, with its missionary empire spanning the globe supported by extensive letters (I saw Matteo Ricci’s Lettere [1580-1609] flash past during my unproductive Jesuit catalogue searching), so in some ways one might expect that Sinapius might be plugged in to that whole network. Yet he emerged from the [presumably unlettered] kitchen staff at Krumlov, and may have not been primarily inclined to write as much as others. It may well be that there simply are no Sinapius letters out there to be found (probably a bit of Melnik-related decree signing, but not a great deal else).

Yet on the other (Paracelsian) side of Yates’ Rosicrucian divide, we see Georg Baresch’s 1637 letter to Athanasius Kircher which praised the latter’s “unprecedented efforts for the republic of letters”. Plainly the idea of the Republic of Letters was still very much alive in the pre-Kircher years: but the question inevitably remains, hanging awkwardly in the air – where have all those letters gone? Were they lost or destroyed, or are many simply lying uncatalogued in private archives?

Incidentally, Christopher Clavius is a famous letter-writing Jesuit mathematician: while François De Aguilon first used the word “stereographic” (for astrolabe-style projections), and his book on optics (Opticorum libri sex philosophis juxta ac mathematicis utiles ) had illustrations by Peter Paul Rubens.

For the voluminous scientific correspondence of Peiresc (1580-1637) who left about 3200 letters and Marin Mersenne (1588-1648) who left around 1100, you might try trawling through the “Correspondance du P. Marin Mersenne”, 16 vols. (1932-1986) or Ismaël Boulliau’s (1605-1694) 5000 unpublished letters. Even though these may well all fall just past our particular time-frame of interest, you’ll never know if you don’t look. [For Boulliau, see Robert Hatch’s chapter 4 in The formation and exchange of ideas in seventeenth-century Europe].

I don’t know: basically, I experience alternating waves of optimism and pessimism about the Voynich Manuscript’s post-1600 history – there’s too little and too late. I get the feeling that Sinapius is a bit of a cul-de-sac, and that we should be looking earlier and towards Southern France for a brief flash of our mysterious herbal manuscript inside the correspondence of the day. But what letters are out there? How would we ever find them?

As I mentioned recently, I’m working my way through James E. Morrison’s book “The Astrolabe”: seeing so many astrolabes at the Museum of the History of Science in Oxford was good fun, but I still want to get all the maths and celestial mechanics straight in my head – I’m never really happy until I get Art and Science in some kind of balance. Curiously, I worked for a camera company (/*you know who you are*/) not so long ago where stereographic projection (as used in astrolabes) is central to its business: isn’t it strange by how little maths has changed over the millennia?

But before the astrolabe, there was a set of objects known as anaphoric clocks (as mentioned by Vitruvius, De Architectura, Book IX, Chap. 8, 8-15): the Tower of the Winds in Athens is generally believed to have had one of these. These are deceptively simple objects, comprising a wire framework top layer (known as a “spider”) to represent the hours of the day, and a backlayer containing both a stereographic projection of the night sky and a circle of peg holes marking the sun’s position as it moves through the zodiacal year.  (All basically as per Morrison, “The Astrolabe”, pp. 33-34).

And now Kansas City is host to a brand new (and really quite funky) anaphoric clock, thanks to local artist Laura DeAngelis (with help from Peregrine Honig), as well as the advice and calculations of Jim “Mr Astrolabe” Morrison himself. If you happen to be in Kansas City unexpectedly (for example, if you click your heels, Dorothy), why not have a look for yourself? The anaphoric clock is in the Oppenstein Brothers Memorial Park, and I think it’s just fabulous (but I would, wouldn’t I?)

TVE, the Spanish national TV company, wanted to interview me about my History Today telescope article. For visual props, they requested a 17th century telescope and a copy of Girolamo Sirtori’s book – fair enough. A quick search of COPAC revealed eight copies across the UK: but what jumped out at me from the list was that there was a copy at the Museum of the History of Science (“the MHS”) in Oxford, which I knew had a fair few telescopes – and so I suggested the interview be carried out there. Plus, I’d wanted to go there for years and years. 🙂

All of which is how I ended up having a nice day out in Oxford. Though the MHS has all kinds of historical scientific gubbins (particularly the basement, which vividly brought to mind Thomas Dolby and Magnus Pyke singing “all my tubes and wires and careful notes / and antiquated notions“), you can’t help but notice its collection is dominated by astrolabes, astrolabes, and more astrolabes. Did I mention they have a beautiful spherical astrolabe too? You get the basic idea: it’s Astrolabe City.

After the interview, I went downstairs to the MHS library to look at their copy of Sirtori’s book for myself (I’d only ever seen scans of it). I also played “I’ll show you mine if you show me yours” with Gemma Wright, the Head Librarian: I showed her my copy of Jim Morrison’s very cool book “The Astrolabe”, while she showed me the MHS’ copy of John Lamprey’s 2007 English edition of Stoeffler’s Elucidatio (also very neat, a snip at $50 + S&H). Errrm… I’m not quite sure why I’m making myself look like “ubergeek of the week” here, so perhaps I ought to stop…

As an aside: though the steak & ale pie in The White Horse (the pub opposite the MHS) was OK, their Dark Star “Sunburst” was epic – just like being in a beer festival (only without a covers band playing “Mustang Sally” too loud, thank goodness). Just in case you ever happen to be thirsty in Oxford! 😉

Here’s a nice bit of craft by someone called “iisaw” (Eric Coyote Elliott), who’s made a fabulous astrolabe-like instrument and posted a couple of pictures of it on the DeviantArt website – click on the picture there for a detailed view.


As you should be able to see, Eric used Voynich lettering (probably the EVA font) when etching enigmatic script on his enigmatic instrument. He writes:-

This “Cosmolabe” is a prop for a movie. The fifteen circular symbols on the front represent different worlds and the signs on the outer rim are components of magical runes used to travel between the worlds. The instument itself is a way to calculate which runes need to be used for opening gates between specific places.

Cool! What’s also nice is the way that it mirrors many of the circular diagrams in Quire 9. As to the text, I can see “qoksheedy” (which only appears on f108v) there, though the phrase it is in does not: so it looks to me like he’s done a nice job of simulating Voynichese, possibly even better than Gordon Rugg’s grilles ever did. 🙂