The Sky as the Oldest Clock: Day Arcs, World-Mill, World-Nail

The sky turns

Point a camera north on a clear night and expose for an hour, and you get a picture made not of points but of circular arcs: every star draws a trail, and all the trails circle the same spot. The Earth rotates, and so, for the observer, the sky rotates instead – everything up there describes a full circle in the course of a day. The visible portions of these circles are the day arcs (diurnal arcs); the Sun's arc from rising to setting is only the most familiar of them.

One single point stands still: the celestial pole, the Earth's axis extended into the sky. Today the Pole Star stands so close to it that to the naked eye it does not move while everything wheels around it. Stars near the pole never set; they are called circumpolar and can be seen on any clear night of the year. Even the pole itself is not fixed forever: the Earth's axis traces a slow circle once every 26,000 years or so (the precession), and in the Viking Age today's Pole Star still stood noticeably off the pole – the centre of the wheeling sky was then a starless patch.

The sky, then, is a clock with several hands. The Sun shows the time of day and, by the height of its arc, the season – from this grow the solar calendars. The Moon counts the months with its phases – from this grow the lunar calendars. And whoever reads both hands together builds a lunisolar calendar, as most cultures of Eurasia did. Up to this point no ancient source is needed: this clock hangs over every night sky, and every culture that looked up has read it.

The question this article is about begins after that: how did the North imagine this turning? Three images have come down to us, attested or inferred – a mill, a nail, a whirlpool. They rest on very different footings, and those differences are exactly what makes them worth a close look.

The world-mill

Andreas E. Zautner opens his book on the Germanic lunar calendar – the authoritative reference of this project – with a chapter whose title this section borrows: "The world-mill is turning".[1] The word "world" itself points that way: Old High German weralt is a compound of wer ("man", as in "werewolf") and -alt ("age") – it means the age in which human beings live. "World" was a word for time before it became a word for space. For the cosmos as a built structure there was the word weraltzimbar, the "world-chamber" or "world-timberwork" – recorded, however, only in the works of Notker of St Gall around the year 1000, as a translation of Latin machina mundana; whether it is older than its Latin model cannot be said.[2]

This world-structure does not stand still. In the Edda the rotating principle bears a name: Mundilfæri. The poem Vafþrúðnismál introduces him in stanza 23 (prose rendering ours):

"Mundilfari he is called, the father of the Moon and likewise of the Sun; each day they shall wheel across the heavens, to serve mankind as the year-counter."[3]

Two things in this stanza are attested, and both carry far. First, the role: Mundilfæri is the father of Sun and Moon – the two great hands of the sky-clock are his children, just as in Snorri's Gylfaginning.[3] Second, the office of those children: they circle "as the year-counter for mankind", Old Norse ártali. The Eddic poem Alvíssmál assigns the same word as the Moon's name among the elves, and stanza 25 of Vafþrúðnismál repeats that the gods created the Moon's phases "to tell the times of the year".[4] In the Edda the Moon is expressly installed as a timekeeper. From this ártali the app Ártala and this website – jahrzaehler.de, German for "year-counter" – take their names; how the counting works in detail is set out in the article on the Germanic lunar calendar.

The name Mundilfæri itself is harder, and here interpretation begins. One reading (Andreas Nordberg, adopted by Zautner) hears Old Norse mǫndull, the wooden handle of the rotary quern, plus -færi: "the one who sets something in motion" – Mundilfæri would be the one who sets the world-mill turning. The other reading hears mund ("time, point in time") and the ferryman (ferjo): the "ferryman of time" who carries Sun and Moon across the sky, as on Bronze Age imagery.[1] Both readings are well argued, neither is provable – only the fatherhood is attested.

That the mill, of all things, was the obvious image has a down-to-earth reason: the rotary quern was the turning device of everyday life, its runner stone circling a fixed stick at the centre. And at least one medieval Icelandic scholar wrote that very comparison down. An Icelandic encyclopedic manuscript (AM 685 d 4to) says that Sun, Moon and stars travel from east to west "in the same way as the quern turns around the mill-handle, so turn the heavens" – a sentence missing from the text's Latin model, and therefore an Icelandic addition.[5] The image of a mill in the sky was there in the North: in writing, medieval, in scholarly prose.

The pillar and the nail

A mill turns on its axle. Take the world-image seriously and you must ask: what is the axle of the world? Here the sources answer twice – once with a pillar, once with a nail – and both answers deserve a careful look at what is actually written and what has been read into it.

The pillar is the better-attested part. Between 850 and 865 the monk Rudolf of Fulda, in the Translatio Sancti Alexandri, describes the sanctuary of the heathen Saxons: a mighty wooden trunk raised on high under the open sky, called Irminsul in their own language, in Latin a universalis columna, quasi sustinens omnia – a "universal column, as if upholding all things".[6] The Frankish Royal Annals report that Charlemagne had this sanctuary destroyed in 772. A world-bearing pillar is thus attested for the continental Saxons of the eighth century – with a footnote that honesty requires: Rudolf's chapter on the Saxons is largely compiled from Tacitus and Einhard, but the Irminsul sentence itself has no identifiable model and counts as his own information.

In Iceland, five centuries later, the pillars stand indoors. The Eyrbyggja saga (chapter 4) describes the temple-farm of the chieftain Þórólfr: "Inside stood the high-seat pillars, and in them were nails; those were called reginnaglar"[7] – literally "god-nails" or "holy nails". The text says no more. What the nails were for, what they meant – the saga is silent, and Fritzner's great dictionary simply puts a question mark next to the word reginnagli. The oldest attestation of the word points in yet another direction: around 1030 the skald Þórarinn loftunga calls the dead king Olaf the Saint a reginnagli of the Latin book-language – a Christian metaphor for "holy fixture", with no star in sight.[8]

And the "world-nail"? The word veraldarnagli exists – exactly once. It stands in a word-list of nail terms in a fragment of the Snorra Edda (AM 748 4to), filed between a boat-nail, a stay-nail and the proverbial nail of caution, without one word of explanation.[9] The claim, often repeated in popular accounts, that the word appears in the Rímbegla, the Icelandic computistic handbook, is false: the printed edition of 1780 contains not a single nail word – we checked.[9]

How did a word-list entry become the name of the Pole Star? That is not transmission but a history of interpretation, and it can be dated step by step. In 1910 the Danish folklorist Axel Olrik was the first to join reginnaglar, veraldarnagli and the Irminsul into one chain: the nail, he argued, was the cult nail set at the top of the world-bearing pillar – of the Pole Star Olrik writes nothing.[10] The star was brought in by the Finnish historian of religion Uno Holmberg in the 1920s, with material that is, in itself, superbly documented: the Sámi call the Pole Star boahje-navlle, the "north nail" that props up the sky; Estonians say põhjanael, "north nail"; Nenets, Koryaks and Chukchi speak of the "sky-nail" or "nail star" around which the stars circle like tethered reindeer around a post.[10] The Lapland traveller Knud Leem had already described a Sámi offering-pillar with an iron nail driven into its top in 1767. In 1934, finally, Otto Sigfrid Reuter drew the equation in so many words: "The 'world-nail' is thus nothing other than the celestial pole or the Pole Star." Reuter's own build-up to that sentence is one long cascade of subjunctives ("if one wishes … then one may … entertain the possibility"), and where he projects the image back to the second century he leaves all evidential ground; his work, moreover, arose in a völkisch milieu and can only be used at a source-critical distance.[10]

One linguistic detail makes the case more tantalising: the Old Norse word nagli was borrowed, as a word, into Finnish (naula), Sámi (nav'le) and Estonian (nael).[11] The peoples for whom the "sky-nail" is genuinely attested use a North Germanic word for it – which makes a shared old conception conceivable. Yet a borrowed word proves no borrowed star-lore; the direction the idea travelled remains open.

Today's scholarship, at any rate, does not carry the equation unanimously. Terry Gunnell, one of the leading scholars of Old Norse religion, translates the Eyrbyggja passage soberly as "nails, that were called holy nails" and manages his whole interpretation of the Icelandic hall without astronomy – cosmologically he reads the pillars, as a counterpart of the world tree, not the nails.[12] Margaret Clunies Ross reads the oldest attestation, the Olaf stanza, as consistently Christian and liturgical.[12] And the standard German reference work, Rudolf Simek's Lexikon der germanischen Mythologie, reads the nails purely as cult objects, lists the "world-nail" only as a word surviving from lost poetry, and holds it uncertain whether the nails are pagan at all – with no mention of the Pole Star.[12] Summed up honestly: two genuine Old Norse words, one well-documented folk-astronomy motif among the neighbouring peoples, and between them a bridge built a good hundred years ago by scholars – not by the sources. What can be said is this: an Old Norse word for "world-nail" is recorded, and since Olrik and Holmberg scholarship has interpreted it as a name for the celestial pole – an image that Sámi, Finns and Siberian peoples genuinely know for the Pole Star. What cannot be said is: "The Germanic peoples called the Pole Star the world-nail."

The whirlpool

The world-mill left one more image behind, and this one stands on firm source ground again. In Skáldskaparmál Snorri tells of the magic mill Grotti, which grinds whatever it is told to grind. The sea-king Mýsingr seizes it and has the giantesses Fenja and Menja grind salt at sea until his ship sinks under the load:

"They had ground only a little while before the ship sank; and there remained a whirlpool (svelgr) in the sea, where the water falls into the eye of the mill. Then the sea became salt."[13]

The ocean whirlpool is here, literally, the eye of the sunken mill grinding on at the bottom – and in passing, the myth explains why the sea is salt. The same nail word-list that contains the veraldarnagli also holds two words Reuter read as "island-mill" and "eddy-mill" for the circling world-ocean – an interpretation, but one that fits the Grotti image.[13] And our word maelstrom still carries the grinding in its name: it was borrowed from Dutch maalstroom – malen means "to grind", also "to turn" – and originally named the most famous tidal whirlpool of Europe off the Norwegian coast, the Moskstraumen by the Lofoten islands.[14]

At this point a question suggests itself, and we ask it openly: do the images join up? A pillar upholding all things; a nail at the pole around which the sky circles; a mill that turns the world; a whirlpool as its eye in the sea – did the pillar, in the end, stand as the mill's axle at the centre of this whole world-picture? The sources' answer is sobering: no surviving text connects pillar, nail, mill and whirlpool with one another. The Irminsul stands in the continental eighth century, the Grotti whirlpool in Icelandic transmission of the thirteenth, the world-nail in a word-list without context. The grand synthesis that fuses all the parts into one system has been attempted more than once in the twentieth century and stands today as a textbook case of over-interpretation.[13] What genuinely remains is more modest and more beautiful: four images for one and the same observation. The sky turns – and the people of the North thought that turning through the things that turned in their daily lives.

Reading the sky again

Of this article's four stations the first matters most: the sky-clock is still running. The same pole stands over every clear night sky; the same Moon counts the months as it did when an Eddic poet called it ártali. Only the reading of it has fallen out of practice. That is exactly where the app Ártala comes in: it reads the sky-clock by the rules of the Germanic lunisolar calendar – computing moon phases and months astronomically, even offline, showing leap months and festivals, source-based and ad-free. If you want to know which lunar month you are living in right now, you will find it for web, Android and iOS on the Ártala homepage.