The Roskilde Viking Ship Museum

News of the terrible stormsurge that almost washed away the Viking Ship Museum in Roskilde, Denmark, earlier this month, brought up memories of my visit there in 2006, when I was researching my book The Far Traveler: Voyages of a Viking Woman.

Before then, when I imagined a Viking ship, I thought of the Gokstad ship, which I'm gazing at here in a photo from 1984. Found in the late 1800s in a burial mound in southern Norway, the Gokstad ship has the spareness and elegance of line that seem to me the epitome of a Viking ship. I’m not alone: closeups of its hull, head on, are reproduced on everything from magazine covers to Christmas ornaments as the emblem of the Vikings.

So I was disappointed at first to learn that the ship Gudrid the Far-Traveler sailed on to Vinland in North America did not look like this. Hers was a knarr, a cargo ship, like the replica Saga Siglar that sailed with copies of the Gokstad and Oseberg ships down the coast of North America in 1991. From the Ellis Island ferry, I had watched the three Viking ships sail into New York Harbor, side by side. In my notebook I wrote:  "Saga Siglar is so squat and tubby compared to the others. It’s as if someone cut her too short."

Saga Siglar (the name means "Saga Sailor") was based on a ship recovered from the seabottom near Skuldelev, Denmark, by Ole Crumlin-Pedersen, whom I met in 2006 at the Viking Ship Museum in Roskilde. Tall, fair, white-haired, and smartly dressed in sailor's white, Crumlin-Pedersen had recently retired from the museum that housed his accomplishments: scraps of five Viking ships in five different styles, from a fishing boat to a dragonship, and a dock full of replicas made to their patterns. Nine more ships—found sunk in the museum's own harbor when they were expanding their exhibit space—were then in various stages of processing. One, the largest by far, a slim dragonship that carried up to 40 pairs of oars, is now the centerpiece of the Viking exhibition that just closed in Copenhagen and will be opening in London in the spring.

Photo by Katrin Driscoll

With a childlike smile and a courtly bashfulness, Crumlin-Pedersen explained to me how he knew that the tubby model was what the sagas meant by a knarr. "It’s because of the nickname for women in the Icelandic sagas: Knarrarbringu. 'Knarr breast.' Look at it from the front. It comes right up like this—" He pantomimed a woman's tight waist and heavy breasts.

"The replica ships going to Vinland should not be based on Gokstad," he continued, more seriously, "they should be based on this knarr, on Skuldelev 1. Gokstad is a combined sailing and rowing vessel, for a large crew. Skuldelev 1 is definitely a cargo ship. There's only a few oars for turning the ship in the wind or in harbor—it's a pure sailing vessel. Six men, working day and night, could handle it. On the other hand, you could have any number of people on board. You could move a farm with livestock and goods—but you wouldn't take more than one farm. Maybe to go to Vinland you would have wanted a vessel slightly larger than Skuldelev 1, but it would have been this same type of vessel."

The five Skuldelev ships had been scuttled at the head of the fjord to keep raiders from the Danish royal residence at Roskilde. Legend had it that they dated from Queen Margarethe's reign in the 1400s. But when parts of the barricade were removed by fishermen in the 1950s, to clear a deeper passage for their motorboats, Crumlin-Pedersen thought the bits he saw were Viking work. Trained as a maritime engineer, he signed on as a deep-sea diver to map out the wrecks, then, after a stint in the Navy, was hired by the Danish National Museum as a ship archaeologist. The Skuldelev site would be his training ground.

"Underwater archaeology was only just starting then," he told me as we toured the docks and warehouses and hands-on exhibits outside of the museum proper. "I went to the first conferences in Italy and London, and my colleagues tried to convince me that I should come to the warm, clear water of the Mediterranean, not stay in the cold, muddy water here. I insisted in exploring the potential here. It turned out to be very rich.

Photo by Katrin Driscoll

"We had thought the site was so damaged we could do no harm," he continued. "We had no experience. We could start there and continue on to more important sites. The first year we cleared the passage and found not one, but two ships. The next year, it was not two but four. The next year it was not four but six." (Later they would learn that ships number 4 and 6 were parts of a single widely-scattered vessel.)

"So we built a coffer dam. Sometimes it's a good thing to come from another education. As an engineer, I could come up with ideas and principles for the retrieving of ships that have become standards all over the world."

The coffer dam drained the fjord around the site. Then the problem was to lift the shattered wood out of the mud, while keeping it from drying out and disintegrating. "You keep the wood in water all the time until it can be treated with polyethylene glycol," Crumlin-Pedersen explained. A type of plastic, polyethelene glycol crystallizes within the wood cells. This plasticized wood can then be heated and gently pressed back into shape. "That brings out the lines of the boat."

Those lines are so various, just among the replica ships afloat in Roskilde harbor, that it's hard to say they’re all "Viking ships." The tubby knarr, 52 feet long and a buxom 16 feet wide, is docked beside the dragonship Havhingsten ("The Sea Stallion"), 98 feet long but a slender 12 feet wide. A smaller cargo ship, a byrding of more "elegant" proportions, carried only four-and-a-half tons of cargo to the bigger knarr's 24 tons, while a smaller warship, called a snekke or "snake," could only handle 30 warriors to Sea Stallion's 80.

Photo by Katrin Driscoll

And then there's the toy-sized fishing boat, 37 feet long by 8 feet wide, on which Crumlin-Pedersen signed me up as an oarsman when a German TV personality wanted to take a Sunday-morning ride. Nicely maneuverable in the narrow harbor (even with a raw crew brand-new to the oars), it seemed precariously low to the waves once the sail was up. Yet when they compared the pattern of the tree-rings in the original ship's pine timbers to wood samples from throughout the Viking world, they found a perfect match with the wood of the Urnes Stave Church in Sognefjord, Norway; the ship had been built there and had sailed the 500 miles to Roskilde at least once. By the time it was sunk to blockade the fjord, it had been patched in several places and refitted to be a small cargo ship, the rowlocks taken off and an extra strake added to give it a little more height.

All five Skuldelev ship types, Crumlin-Pedersen believes, developed after 900 out of the basic Gokstad style. "The development of cargo vessels seems to be a very late one in Scandinavia," he explained over a lunch of pickled herring and brown bread in the museum’s dockside restaurant (right under which, he pointed out, another longship had been found, 20 feet longer than Sea Stallion). "They didn’t have proper cargo vessels until the 10th century. I think that's because it was too dangerous to go out with a load of valuable cargo without a sufficient number of people to protect your goods. The Gokstad ship was capable of carrying eight to 10 tons of cargo, but also a sufficient crew to defend it. Then in the 10th to 11th centuries, we have the development of cargo ships and the transformation of warships into ships that couldn't carry cargo. I see that as a sign of royal control of the sea. It was one of the main jobs of the king, to keep trade safe."

The cargo ships got tubbier (and more practical), the warships got longer and sleeker and swifter; the principal of their design, according to Crumlin-Pedersen, being the "sporting element": fierce competition among royal Viking crews. One of these late longships is 11 times longer than it is wide and made from enormous oak trees, each thin plank over 32 feet long. "For the really royal ships, the shipbuilder had access to trees no one else could touch," Crumlin-Pedersen told me. "Such a ship as this is an amazing machine!" Racing such a royal ship, he said, must have been the sporting experience of a lifetime.

To read about the Viking Ship Museum's battle with the stormsurge, and see some spectacular photos, go to the museum's website, here: http://www.vikingeskibsmuseet.dk/en/about-us/news-room/photo-series/billedserie-vikingeskibene-stod-stormen-igennem/#c15886

There's also a film about the storm, here: http://www.vikingeskibsmuseet.dk/en/about-us/news-room/photo-series/billedserie-stormen-time-for-time/film-om-stormen/#c15878

Join me again next Wednesday at nancymariebrown.blogspot.com for another adventure in Iceland or the medieval world.

The Ornament of the World

Spain doesn't figure much in tales of the Vikings. In The Viking Age: A Reader, which I wrote about in an earlier post (here), you can see why. As one medieval chronicler explains, the Vikings, whom the Moors called "Madjus," "arrived in about 80 ships. One might say they had, as it were, filled the ocean with dark red birds, in the same way as they had filled the hearts of men with fear and trembling. After landing at Lisbon, they sailed to Cadiz, then to Sidona, then to Seville. They besieged this city, and took it by storm…" But their success didn't last.

"When war engines were used against them, and reinforcements had arrived from Cordoba, Madjus [the Vikings] were put to flight. They [the Moors] killed about 500 of their men, and took four of their ships with all their cargoes. Ibn-Wazim had these burnt, after selling all that was found in them. Then they [Madjus] were defeated at Talyata on the 25 Safar of this year [11 Nov 844]. Many were killed, others hanged at Seville, others hanged in the palm trees of Talyata, and 30 of their ships were burnt. Those who escaped from the bloodshed embarked. … and were no more heard of."

It's not surprising the Moors repulsed the Vikings so efficiently, for the Muslim caliphate of al-Andalus was the most technologically advanced civilization in Europe at the time. Arabic numerals, the efficient 1-2-3 that replaced the clumsy i-ii-iii, came to the West from Baghdad through al-Andalus during the Viking Age, along with many other advances in mathematics, astronomy, agriculture--even paper-making.

I learned this when writing The Abacus and the Cross, my biography of the pope who reigned when Iceland was converted to Christianity in the year 1000. Pope Sylvester II may even have corresponded with King Olaf Tryggvason, who is credited with christianizing Norway; early historians write of a letter (now lost) in which the pope told the king to quit using runes.

Born Gerbert of Aurillac in about 950, Pope Sylvester II studied mathematics and astronomy near Christian Barcelona from 967-970. (I think of them as his college years.) He learned about Arabic numerals and used them to create a new kind of abacus, or counting board, with which he later taught arithmetic in the cathedral school at Reims, France.

Curious to know more about what Spain was like when young Gerbert arrived, I turned to a book by Maria Menocal of Yale University: The Ornament of the World: How Muslims, Jews, and Christians Created a Culture of Tolerance in Medieval Spain (Little, Brown 2002). Inspired by what I read, I contacted Menocal and requested an interview. She was then in Spain—I wish I had joined her! Instead, I waited until she returned to Yale University and met her there in January of 2008. I attended a lecture she presented and accompanied her and her graduate students to dinner; the next morning I interviewed her about her work.

A year ago, Maria Menocal died of melanoma [http://news.yale.edu/2012/10/15/memoriam-mar-rosa-menocal]. Remembering her insight and her generosity, I want to share a bit of what she taught me about al-Andalus.

 “Cordoba, by the beginning of the tenth century, was an astonishing place, and descriptions by both contemporaries and later historians suffer from the burden of cataloguing the wonders,” she wrote in The Ornament of the World. It was nearly half as big as Baghdad, the largest city of its day. It held hundreds—maybe thousands—of mosques. Running water from aqueducts supplied nine hundred public baths. The goldfish in the palace ponds ate 12,000 loaves of bread. The paved streets were lit all night. The postal service used carrier pigeons. The munitions factory made 20,000 arrows a month. The market held tens of thousands of shops, including bookshops: Seventy scribes worked exclusively on producing Qurans. The Royal Library in Cordoba, just west of the Great Mosque, was said to contain 400,000 books in 976. (By comparison the greatest Christian library of the time, at Bobbio, Italy, held 690 books.)

Menocal took the title of her book from a poem by the nun Hrosvit of Gandersheim, who met an ambassador from Cordoba in 955 at the German court of Otto the Great. “The brilliant ornament of the world shone in the west,” Hrosvit wrote. “Cordoba was its name and it was wealthy and famous and known for its pleasures and resplendent in all things, and especially for its seven streams of wisdom.”

Significantly, only about 50 percent of Cordoba’s 100,000 residents were Muslim. Among the caliph’s viziers, or advisors, was Hasdai ibn Shaprut, who was Jewish, and Bishop Racemundo (the ambassador Hrosvit met), who was Christian. The Quran teaches that, since Moses and Jesus had both been given books by God, Jews and Christians were fellow “Peoples of the Book,” and thus to be tolerated. In al-Andalus, Menocal explained, they “were dealt with under the special terms of a dhimma, a ‘pact’ or ‘covenant’ between the ruling Muslims and the other book communities living in their territories.” They were not forced to convert, but could practice their religions—as long as they did so quietly and didn’t proselytize. Other than having to pay taxes—which Muslims did not—they were not excluded from the city’s social or economic life. They could, and did, fight in the army. Depending on the ruler’s interpretation of the law, they could advance to the highest political posts, as Hasdai and Racemundo did.

Lecturing on her work in the faux-Gothic humanities center at Yale University, Menocal marveled at the fact that medieval Spain has suddenly become relevant. “We now inhabit a previously inconceivable universe, a universe in which the study of the history of medieval Spain can shed light on modern political problems. What does al-Andalus mean? It’s either about 'conviviencia' or 'reconquista,' either about how the three Abrahamic religions could coexist or how they could not.”

“The issue that’s interesting in this period,” Menocal told me the next morning, as she bustled about her office grabbing up papers to take to a departmental meeting, “is how one carves out the wherewithal to have the coexistence of three monotheistic religions that are by definition intolerant.

“Islam arises under conditions where they’re a priori already dealing with these two other monotheistic religions,” she continued. “Medina had a huge population of Jews. For whatever reasons—and they are real political reasons—Islam created the dhimma. I think it does translate into something we could call tolerance. It’s discriminatory, but pretty good, especially in comparison with the other possibilities.

“In Spain it was applied generously, and it provided the basis for much more complex forms of cultural interaction.” Arabic was the lingua franca, not just the language of religion. “To Christians, it was fascinating and very attractive to have this language that was flexible enough to write erotic poetry with and to speak to God with. There’s this whole unimaginable universe that being Arabophone gave you access to: poetry, all the scientific translations coming from Baghdad…”

Or, as she wrote in The Ornament of the World, “This was the chapter of Europe’s culture when Jews, Christians, and Muslims lived side by side and, despite their intractable differences and enduring hostilities, nourished a complex culture of tolerance.” In al-Andalus, “men of unshakable faith saw no contradiction in pursuing the truth, whether philosophical or scientific or religious, across confessional lines.”

It was a powerful combination and produced a civilization to whom an attack of the Vikings was like the descent of a flock of red birds--a flock easily chased away.

Join me again next Wednesday at nancymariebrown.blogspot.com for another writing adventure in Iceland or the medieval world.

Remembering the Scientist Pope

“See those towers?” Costantino Sigismondi points to the two square Romanesque towers crowning Saint John Lateran. “We can imagine Gerbert up there looking at the stars.”

In 2008, while researching my biography of Gerbert of Aurillac, the French mathematician who became Pope Sylvester II, I visited Rome. I met my guide to the city, Costantino Sigismondi, through his website, where he had posted all of Gerbert’s known works. This year, on May 10, Sigismondi has organized a full day of lectures devoted to Pope Sylvester II at Rome’s Sapienza University. On May 12, a mass will celebrate the 1010th anniversary of Gerbert’s death. I wish I could join Sigismondi for the festivities. He's one of those rare people who brings light to the Dark Ages.

Sigismondi, an astrophysicist, teaches the history of astronomy at the University of Rome. In 2000, a friend reading Sky & Telescope chanced upon an article about “Y1K’s Science Guy,” Gerbert of Aurillac. She sent it to Sigismondi, who was astonished. Why hadn’t he known about The Scientist Pope? Sigismondi immediately contacted the Vatican and, with the pope’s support, began planning a series of lectures and events to commemorate the millennium of Gerbert’s pontificate (999-1003), including a grand requiem mass in the cathedral of Saint John Lateran in 2003.

Now we were in the square on the north side of the basilica; we turned to see an obelisk covered with hieroglyphics. “That wasn’t there when Gerbert was pope. We need to go to the Campo Marzio, close to the Pantheon. Ten years before Christ, Augustus put an obelisk there to make a sundial. One of the legends of Gerbert, you remember—William of Malmesbury tells it—is the story of Gerbert and a servant walking through the Campo Marzio, and Gerbert suddenly understands the Augustine obelisk. This is the story of the buried treasure.”

William of Malmesbury, writing in the 1120s, describes not an obelisk but “a statue … pointing with the forefinger of the right hand, and on its head were the words ‘Strike here.’” It was all battered with blows from men who had done the obvious. Gerbert found “quite another answer to the riddle. At midday with the sun high overhead, he observed the spot reached by the shadow of the pointing finger, and marked it with a stake.” He returned at night with a servant and, presumably a shovel. They quickly found themselves in “a vast palace, gold walls, gold ceilings, everything gold; gold knights seemed to be passing the time with golden dice, and a king and queen, all of the precious metal, sitting at dinner with their meat before them and servants in attendance; the dishes of great weight and price.” The palace was magically lit by a sparkling jewel; a golden boy stood opposite it, “holding a bow at full stretch with an arrow at the ready.” Gerbert’s servant, overcome with greed, snatched a golden knife. At once the figures came alive with a roar. The boy loosed his arrow and put out the light. And “had not the servant, at a warning word from his master, instantly thrown back the knife, they would both have paid a grievous penalty.” They covered their tracks and said no more about it.

If this story were set in Reims, I could pooh-pooh it as utter fantasy. But Rome? In 2005, archaeologists were using a coring drill to survey the foundations of Caesar Augustus’s palace on the Palatine Hill. Fifty feet down, the drill plunged into a void. Sending down a camera, the crew discovered a sacred grotto—a round, domed room about twenty-five feet high and twenty-five feet across, covered with mosaics of marble and seashell. In the soft light of the remote-sensing probe, they glittered like gold.

Whether or not Gerbert found buried treasure, if he understood how an obelisk worked as a sundial, he would have understood the Clementine Sundial in the church of Santa Maria degli Angeli. Sigismondi had demonstrated it to me that noon. The church is an architectural pastiche, the interior by Michelango, the exterior a ruined Roman bath. The meridian line of the sundial is not squared with the church—it was added later, the church being chosen for the purpose because of its stable Roman walls and suitable dimensions. The pinhole that lets in the sunlight was set into a great bronze sculpture of the arms of Pope Clement XI (1700-1721) that cuts into one of Michelangelo’s ornate arches. New marble mosaics were set into the floor to create the zodiac images that flank the line, which is made of brass.

“The meridian occurs in this line,” Sigismondi said, putting a blank sheet of white paper near the line so that the faint sun on this cloudy day was more visible. “It’s different for every day. It goes to 12:24 in February, comes back to 12:20 now in March. And back to 12 in October. This is the so-called equation of time. If you take this and put it to local noon time, noon”—when the image of the sun crosses the line—“equals halfway between dawn and sunset.

“If mass is at noon,” he added, “sometimes the transit will happen during mass. If mass is at 12:30, then the faithful can attend mass, the astronomer can do his work, and the faithful astronomer can do both. The priests here are very open. They moved the mass to 12:30 for this reason.” And every day that he works in the cathedral, Sigismondi also takes part in the 12:30 mass, volunteering to read the scripture and take the offerings.

“I am practically the resident astronomer of Santa Maria degli Angeli,” he said. He has held conferences and astronomy classes in the church; on a side table, surrounded by sacred literature for sale, is a one-euro pamphlet he wrote called “Astronomy in the Church.” The pamphlet gives his email address if anyone would like further information on this partnership between religion and science.

Sigismondi has also used the sundial for original scientific research. “I measure this meridian line with video cameras to take scientific information as accurate as possible.  Looking at the sun, it is possible to measure all the parameters of the solar orbit with a precision difficult to achieve with a normal telescope. You can measure the angles of the sun with greater precision because there is no lens—there is no border effect. The border effect of a lens is remarkable. The pinhole, on the other hand, is aberrationless. The only abberation is due to the atmosphere.

“What’s the link between this meridian line and our Gerbert? There’s no real link, because this line was built seven centuries later.

“But it was built by a pope, by a successor of his, Clement XI. He became pope on November 23, 1700. By the first of January, the astronomers were already building this line for him. Only seventy years after the Galileo affair, the pope was building this scientific instrument in the church—and this instrument can distinguish between the Copernican system, with the earth going around the sun, and the Ptolemaic system, with the sun going around the earth. With this instrument of the pope’s, you can prove that the earth goes around the sun.

“And this was possible in Gerbert’s time. If you use only the duration of the seasons, then Ptolemy works. If you can see the image of the sun—as you can with this sundial—then Ptolemy fails.”

Sigismondi speculates that this kind of sundial was the sensational object that Gerbert made for Otto III in Magdeburg—what Thietmar of Merseburg called an horologium, a “time-keeper,” translated variously as an astrolabe, a nocturlabe, a clepsydra, a celestial sphere, or a sundial. “This kind of clock is very easily made by someone like Gerbert,” Sigismondi said, “someone brilliant who understood the idea of using a tube to observe the stars, someone who could make his spheres. A sighting tube is not so different from the type of camera obscura you have here. The function of the church is just to make a dark space so that the light coming through the pinhole can be seen.

“We can’t say that this is what Gerbert made at Magdeburg, but there is room to dream in the history of science. We can’t say he didn’t. And it’s something he could have done. It’s plausible. Gerbert was about four hundred years  ahead of the contemporary people, scientists and scholars included. Many of them understood that he was really outstanding. He was very respected as pope. I would like to see him sainted, or at least blessed. Abbo was sainted, and Gerbert was better than Abbo.”

If anyone could do it, Sigismondi could. A self-proclaimed “faithful astronomer,” he is equally at home in his astrophysics laboratory and in the Vatican; his university website features a photo of him kneeling before the pope. An eager teacher, he had led me on an enthusiastic all-day tour of Rome, highlighting the priest who was carving a new sun to reconstruct a medieval armillary sphere much like the one Gerbert had made; the Jesuit who had originated the field of astrophysics; the pope who had studied the dimensions of the sun.

The more time I spent with him, the more he seemed like Gerbert himself—Equally in leisure and in work we both teach what we know, and learn what we do not know. Or, perhaps like Gerbert’s beloved friend, the sweet solace of his labor, a man with the same first name: Costantino Sigismondi was Gerbert’s twenty-first century Constantine, who would keep the story of The Scientist Pope alive.

Join me again next Wednesday at nancymariebrown.blogspot.com for another writing adventure in Iceland or the medieval world.

How to Make a Medieval Book: Part III

On the tenth Thor’s Day of summer in the year 1000, Iceland became Christian by parliamentary decree at the Althing. Lovers of JRR Tolkien’s or Neil Gaiman’s books—or of any fantasy novel, movie, or game—should celebrate that date, because the fantasy genre would hardly exist if the medieval chieftain Snorri Sturluson had not learned to write.

Writing and religion go hand-in-hand for Christians are “people of the book”: Christianity’s most powerful symbol is not the cross, but the Bible. Foreign priests, finding no books in Iceland, introduced the necessary ink-quill-and-parchment technology in about 1030—thus allowing Snorri Sturluson, some 200 years later, to write the books of Norse mythology, history, and lore that inspired Tolkien and much of modern fantasy, including Gaiman’s brilliant American Gods.

A missionary bishop named Rudolf, from Normandy or perhaps England, ran a school in the west of Iceland until 1050. He and his fellows showed their Icelandic students how to make parchment.

First they scraped the hair off a calfskin with a sharp blade. This was a harder task in Iceland, where limestone was unavailable, than in continental Europe; a bath in slaked lime made the hair simply fall off the skin. (See my previous post, “How to Make a Medieval Book: Part I.”) In Iceland, the skins were washed in a hotspring, where the mineral-rich water loosened the hair, and scraped again and again.

Another technique was to soak the skins in urine and leave them to rot until the hair came off. A third method involved tying a newly flayed skin to a heifer, with the hair side against the cow’s skin. In a day or two, the hair would be loose enough to pluck off.

When suitably hairless, the skins were stretched on a frame and set in the shade to dry. After rubbing them smooth with pumice (plenty of that in volcanic Iceland), the parchment was made soft and pliable by twisting it and pulling it back and forth through a ring made from a cow’s horn.

           

Quill pens were cut from swan, goose, or raven feathers (also easily come by in Iceland); left-wing feathers were best for right-handed writers because they bent away from the eye.

Ink was made from the bearberry plant, mixed with a clay commonly used to dye wool black and a few shavings of green willow twigs. The mixture was softened in water, then simmered until it became sticky. “Let a drop fall onto your fingernail,” says one recipe. “If it remains there like a little ball, then the ink is ready.” A little bit of gum from the first milk of a young ewe or heifer was added to the ink to make it shiny. (To compare this to ink-making elsewhere in Europe, see my “How to Make a Medieval Book: Part II.”)

The result was ink that was black, glossy, and impermeable to water, which was a very good thing for people who often traveled by ship. Books are rarely mentioned in medieval Icelandic texts, but in one famous shipwreck, a priest is desolate when his book chest is swept overboard. Learning a few nights later that it had washed ashore, he hurried to the spot to dry out his books; it took him six weeks. Mold is the one thing a parchment book cannot survive.

Luckily for us, three parchment copies of Snorri Sturluson’s Edda survived until the 1600s, when they were published. The Edda has been in print ever since, available to be read by Tolkien, Gaiman, and countless other fantasy writers whose work is imbued with the spirit of Norse mythology.

This essay was adapted from my biography of Snorri Sturluson, Song of the Vikings: Snorri and the Making of Norse Myths, published by Palgrave Macmillan.

Learn more at nancymariebrown.com

In Search of the Scientist Pope

The Abacus and the Cross, my biography of the Scientist Pope, Gerbert of Aurillac (Pope Sylvester II), will be out in paperback this fall. To celebrate, here’s a little essay about my quest to discover the pope of the year 1000:

I thought I spoke French, but the young man’s bright sentences blurred and vanished. My redheaded friend, still flirtatious at fifty, was getting through to him a lot faster in smiles and shrugs and a little Spanish, draping her lime-green scarf across his papers, leaning in.

He was not a monk, though this was a monastery.

We had driven the scalloped edge of Catalonia north: mile upon mile of terraced vineyards, white cliffs sheer to the sea. We had not stopped at the castle with its feet in the tide, or at the winery. I was on a quest.

A forgotten French monk had passed this way a thousand years ago, when most of Spain was Islamic al-Andalus, and Arabic was the language of science. His name was Gerbert of Aurillac. He was the first person in the Christian West to teach math using the nine Arabic numerals and zero. In the year 999, he became pope.

We tracked him through Barcelona, Girona, and Vic. We climbed steep stone stairs to hilltop church-fortresses, surrounded by the tinkling of goat bells—at least we climbed halfway up. We both suffer a fear of heights. We were en route to a clutch of churches high in the Pyrenees when I checked my email. I’d asked a Swiss historian for an interview and told him where I was.

Go to Elne cathedral, he said, où il y a une inscription dans la pierre ... Elle est de Gerbert, distribuée sur une croix… An inscription on a stone. About Gerbert. On a cross.

We found the cathedral, a golden-stone pile on its dusty hill. All the streets in town converged on it, staunch and square, its broad doors barred, its windows higher than a stone could be thrown. A gate in the wall opened into a cemetery—a good place for carved crosses, I thought, but found nothing. My friend tried a door. I followed her giggle and found her, tête-à-tête with handsome Romain.

Elne’s cloister was famous for stone carvings—devils and dragons and laughing sprites. Romain unfolded a brochure to pony us through his French. Peut-être this stone? She is très fameux.

C’est une croix, I said.

He shook his head. There were no famous crosses.

Show him your notebook, Ginger hissed.

Indeed! I had copied out the email.

O! C’est votre professeur? Romain pointed to the name, amazed. He had just mailed the Swiss historian photos of names carved in a stone—O!

In the 1960s they had moved the main altar. Lifting the marble top, they spied names carved on the platform beneath. One was cut in the shape of a cross.

Can I see it?

Désolé. Mass is in session. Then we close. Come back tomorrow? Non? I will send you the photos.

But a photo of this stone was not enough.

In 2005, I volunteered on an archaeological dig in Iceland. We excavated a house built just after the year 1000. Medieval books say a woman named Gudrid explored the New World around the year 1000; she sailed back to Iceland and built a house here, on the very farm where we worked. So I called the dig “Gudrid’s house.” The scientists were annoyed. You cannot say that. That’s a story. You have no proof. Not unless you find a stone by the doorstep that reads Gudrid was here.

Of course, we found no such stone.

The story of the Scientist Pope seems equally improbable. Wasn’t the Church anti-science in the Dark Ages? Yet medieval books say Gerbert was sent by his monastery to the border of Islamic Spain in 967 to learn math. That he started a famous science school at Reims cathedral. That he tutored the Holy Roman Emperor and the king of France.

We understand the Dark Ages about as well as I speak French.

Two months later, I returned to Elne. Thanks to my redheaded friend, Romain remembered me. He dug out a flashlight and led me deep into the darkness of the church. Hung flat on a wall was a large gray stone—like a radiator, exactly—a row of wooden chairs brushing up against it. I stood on a chair to get a better view; he aimed the light. Carved on the uptilted edge of the stone, in the shape of a cross, was the name “Gerbertus.”

I traced the letters with my thumb: Gerbert was here.

Join me again next Wednesday at nancymariebrown.blogspot.com for another adventure in the medieval world.

The Pope’s Abacus

When were Arabic numerals introduced into Western Europe? We used to think it was in the 1100s. But scholars studying the life of Gerbert of Aurillac, who became Pope Sylvester II in 999, have pushed that date back nearly two centuries.

People usually think of a Chinese abacus when they hear the title of my biography of Gerbert, The Abacus and the Cross: colored beads strung on wires set in a frame. Gerbert’s abacus was nothing like that.

It was a counting board: a grid of 27 columns, painted on a flat surface. Later, merchants found having a counting board like this so useful that they drew them on tabletops, which they called “counters.” That is why we now do business “over the counter.”

Arabic Roots

To learn about Gerbert’s abacus, I visited Charles Burnett, Professor of the History of Islamic Influences in Europe at the Warburg Institute in London. In 2001, Burnett discovered a copy of Gerbert’s abacus. It was a stiff poster-sized sheet of parchment that had been trimmed down and reused in the binding of the Giant Bible made for the abbot of Echternach between 1051 and 1081.

The Bible is owned by the National Library of Luxembourg, which had unbound it in 1940 in order to photograph the pages. The abacus was taken out of the binding and, Burnett told me, “It got put in a box. It got lost in the library for several years. My friend, the librarian of rare books, was tidying up and found the original of the abacus sheet.” Noticing the Arabic numerals along the top, the librarian immediately thought of Burnett, who has been writing about the Arabic roots of mathematics since the 1970s.

Shortly after Burnett announced his find, a librarian at the State Archives of Trier called with word of a matching copy “written in the same bold capital letters,” Burnett says. It was also made at Echternach.

           

This second abacus was bound into a manuscript along with notes on multiplication and division, the use of fractions, the etymology of the word digit, and a poem on the names of the nine Arabic numerals and zero. These notes can be dated to 993. Burnett writes, “They appear to be written by a single scholar, at different times, who has made frequent erasures and corrections.” Burnett thinks he was one of Gerbert’s students.

How to Calculate

To use his abacus, Gerbert had 1000 apices or markers made out of cow’s horn. They looked something like modern checkers. Each one was marked with an Arabic numeral. To calculate, Gerbert placed the markers on the counting board and shuffled them around. He could get the answer, one of his contemporaries wrote, quicker than you could say it in words.

Using these new Arabic numerals, Gerbert’s abacus introduced the “place-value” method of calculating: The place, or column, where the marker sat determined the value of the number written on it, whether it meant 5 or 50 or 500.

In 2003, Burnett was a visiting professor at the University of California. “When I was teaching in Berkeley, I actually reconstructed Gerbert’s abacus,” he told me. “I found a shop that specialized in games for children. I bought one of these big rolls of paper and these lovely large numbers—they could substitute very well for the apices, I thought. I drew the columns on this paper—not 27 of them. I didn’t get as complicated as all that. It’s perfectly possible to work out how the procedure worked.”

Did Gerbert Use Zero?

A zero marker was not strictly necessary—to make 50, you put a 5 in the tens column and leave the ones column blank. But the poem in the Trier manuscript does include a zero, looking like a spoked wheel, so Gerbert may have used it as a placeholder. The idea that zero was an actual number would not arrive until much later.

“In the 1120s,” Burnett explained, “there was a change-over from the abacus to the algorithm. The big change is using pen and paper. Also the sign for zero. So the main difference between the look of Gerbert’s abacus and look of the algorithm is, with the algorithm you don’t actually draw the lines for the columns and you have a zero instead of an empty column.”

For a thousand years, we have added, subtracted, multiplied, and divided essentially the same way Gerbert taught his students at the cathedral of Reims.

Photos & Links:

Arabic numerals appear on two pages from the notebook of  one of Gerbert’s students, which Burnett dates to c. 993. The second page shown here is a copy of Gerbert's abacus board. (From MS Trier, Stadtbibliothek 1093/1694 fol.)

One of the frescoes by Gabor Szinte in the Church of St Simon near Aurillac shows a young Gerbert learning about Arabic numerals in Islamic Spain. You can learn about the frescoes on the Aurillac tourism website, here.

Read more about Professor Charles Burnett and his work at the website of the Warburg Institute, London, here.

Join me again next Wednesday at nancymariebrown.blogspot.com for another adventure in the medieval world.