How to Make a Medieval Book

For me, the hardest part of making a book is deciding what to say. In the Middle Ages, there was more to it than that, as I learned when researching the technology of book-making for The Abacus and the Cross. This week and next, I’ll share what I found out.

CoolTour Bobbio: 

Today the greatest Christian library of the early Middle Ages—at the Italian monastery of Bobbio—is empty. Half of its 690 books went to Milan in the 1400s; from there, in the 1600s, some were sent to the Vatican. In 1803, after Napoleon shut down the monastery, the remaining manuscripts were auctioned off. Many were bought by the National Library of Turin, which burned down in 1904. “We don’t have even one to show the kids,” Jessica Lavelli told me. “The library in Milan will not even lend us one.”

An energetic young woman committed to Bobbio’s reputation as the library that “saved civilization” (Thomas Cahill, author of How the Irish Saved Civilization, visited Bobbio, which was founded by an Irish monk), Lavelli makes up with imagination what she lacks in resources. She calls her project CoolTour. From October to March, she invites one school group a week into the monastery and teaches them how to make a manuscript; in April and May, it’s thirty kids a day. “They come from all over northern Italy: Milan, Genova, Brescia, Parma, Cremona. Anywhere that’s less than two hours by bus.”

After a tour of the ancient walled town, with its castle on the hill and its hump-backed Roman bridge over the rushing river Trebbia, the children march through the arched gate behind the basilica and into the high-walled monastery complex. They pass through the cloister, its shady, columned arcades opening onto a sunny square where the monks would have had their herb garden, into a pair of bright classrooms; there they are issued goose quills, ink, and parchment. They learn the history of script from hieroglyphics to computer typesetting and how to make a book starting with the sheep.

Parchment: 

In one corner stands a sample of parchment stretched on a drying frame. “I got a sheepskin from a brasserie, a butcher, last spring,” Lavelli told me. “In Italy, it’s common to eat sheep for Easter, so they had many skins. A lamb would be half this size. From one sheep you can get two pages—four sides when it’s folded. From a lamb you only get one.”

How did she learn to make parchment? “From a book. We found a book and tried to do it. It’s a very long process. It takes four days to prepare and one week to dry, so after about ten days we can cut out our page. You dry it not in the sun or in the dark, but in the penumbra. We put it here”—she motioned toward a shady niche in the cloister where high walls block the sun from three directions. “The smell of the skin is not good,” she added, wrinkling her nose. “When it stops smelling, it’s dry.”

According to Pliny’s Natural History, written in the first century A.D., parchment—in Latin, pergamenum—was invented for the king of Pergamos (modern Bergama, Turkey) to break the Egyptian monopoly on papyrus. The sedge used for papyrus was common only on the banks of the Nile. Sheepskins were everywhere.

 The oldest known recipe for turning sheepskin into parchment was written in the Italian city of Lucca at the end of the eighth century. “Place it in limewater,” it says, “and leave it there for three days and extend it on a frame and scrape it on both sides with a razor and leave it to dry, then do any kind of smoothing that you want.”  A twelfth-century manuscript offers more precise—but still somewhat mysterious—instructions on how “to make parchment from goatskins as it is done in Bologna”; this process takes twenty-four days plus drying. Book conservator Leandro Gottscher compared the two methods during a series of experiments one hot summer in Rome in the 1990s. Both made acceptable parchment, though the shorter soaking time made for harder work scraping off the hair.

The limewater is the key to the process. It was made by burning crushed limestone (or marble, chalk, or shells) in a kiln to make quicklime, placing that in a vat or barrel, and adding a little water. The limewater would seethe and bubble and be ready in about ten minutes. Gottscher spread a pulp of limewater onto the skin, folded it, and set it aside for a few days. Other experimenters prefer to dilute the limewater until it is milky and soak the skin. The lime eats into the epidermis, the outer layers of the skin, loosening the hair on one side and the fat on the other.

To remove the hair, rinse off the lime and pull or pluck out whatever hair you can. (Gloves are a good idea—any remaining lime will eat into your skin too.) Next lay the skin over a log or trestle and rub it with a wooden hone, a bone spatula, or a dull knife, a procedure called scudding.

To remove the fat, the hairless skin can be dunked in fresh limewater or rubbed with lime powder, then spread on the trestle, hair-side down, and scudded again. Lean sheep make better parchment than fat ones; excess fat makes the parchment slippery and the ink doesn’t stick. On the other hand, parchment that is scraped too thin can become wrinkly and transparent.

The dehaired and defatted skin is soaked again and stretched onto a wooden frame to dry. To avoid tearing holes, first wrap a corner of skin around a pebble (called a pippin), tie one end of a cord around the pippin and another to a wooden peg in the frame. As the skin dries, tighten the pegs.

While leather-making is a chemical process, parchment-making is a physical process. What’s left after all the soaking and scudding is mostly collagen, long spiraling proteins that form tough, elastic fibers. As the skin dries, these fibers try to shrink. Stopped by the frame, instead the fibers’ structure begins to change.

When it’s dry, the parchment is scraped again, still on the frame, with a crescent-shaped blade called a lunellum (“little moon”), powdered again with lime or chalk to bleach it, and rubbed thoroughly on both sides with a pumice stone to raise a nap. Then it is taken down and cut into sheets of a standard size. The first sheet is easy: a rectangle that, folded, could become four pages of a large book (or eight pages of a small one). Then the cutter has to become creative: A sheepskin is not square. Where the head, legs, and tail were cut off, the skin curves. Scholars often come across manuscript pages with a corner missing—where a page runs into a neck hole. Other blemishes are insect bites (little holes), wounds on the animal (bigger holes), and gashes (where the knife slipped during the flaying); some of these are sewn up, but usually the scribe just wrote around them.

The color of parchment depends partly on the process and partly on the animal it came from. Low-grade parchment could be dark pinkish-brown with a chalky surface, peppered with hair follicles, streaked with scrape marks, or so thin that the ink bled through. Sheepskin, well cured, was “butter-white” or yellowish, but still sometimes greasy or shiny. Goatskin was greyish. Calfskin was the whitest, though the veins could be prominent. The parchment Jessica Lavelli made to show her pupils at Bobbio had a large brown spot. She shrugged. “It was a spotted sheep! I didn’t think it would matter.”

If you visit Bobbio, check out CoolTour and say hello to Jessica for me:

http://www.cooltour.it/

For an overnight stay, I recommend the farm guesthouse San Martino. It is (of course!) a horse farm within walking distance of the town:

http://www.agriturismo-sanmartino.com/

Bobbio has also been recently identified as the town painted in the background of the Mona Lisa. As one newspaper said, “brace for tourists”!

http://www.newser.com/story/109501/art-historian-identifies-mona-lisas-home-town.html

Photos: Saint Luke at his writing desk, from Bernward's Evangelary (Dom Museum Hildesheim). The town of Bobbio, Italy. Portrait of a scribe from the CoolTour Bobbio website. Detail of a Bobbio manuscript, also from CoolTour Bobbio.