The slim volume bound in animal skin represented the best the field of medicine had to offer 500 years ago: a compilation of remedies made from such ingredients as rabbit bones, ox tongue, and chicory.

Yet at some point before the manuscript reached its current resting place, a library shelf at the University of Pennsylvania, an unknown liquid was spilled on its carefully lettered pages. Many of the words are no longer legible.

A book-lover's nightmare? Not for Erin F. Connelly. She sees the unsightly blotches as a research opportunity.

Connelly, a postdoctoral fellow at Penn's Schoenberg Institute for Manuscript Studies, is on a quest to identify old stains in medieval texts. Moldy old stains. Mysterious blemishes that might be traces of the very ingredients written down on now-faded pages, spilled by some early practitioner of the healing or chemical arts. Or could they be remnants of blood from a patient? Drippings from the candle of some scribe from long ago?

Using high-tech scanning equipment, so far Connelly and her partners — from the Library of Congress and the University of Wisconsin-Madison — have begun to analyze stains in two dozen medieval manuscripts.

The team members realize their quest may seem odd to some, but they feel that the essence of a written work lies not only in the words themselves, but in how it was used and passed down through the ages. Even some scholars, Connelly said, need to be reminded that there is value in centuries of grime.

"These are manuscripts that have traditionally been pushed aside and dismissed due to their dirty or stained appearances," she said.

From a practical standpoint, identifying a stain in an old manuscript also would help a conservator determine the best way to handle and preserve it. Some of the stains are expected to contain acids and heavy metals, for example.

But in order to shine a light on these historic dribbles and blobs, the first step was to plunge them into complete darkness.

The cover of a 600-year-old “Harry Potter” book was exposed to a series of colored lights in order to identify mysterious stains, in a library studio at the University of Pennsylvania.
MICHAEL BRYANT / STAFF PHOTOGRAPHER
The cover of a 600-year-old “Harry Potter” book was exposed to a series of colored lights in order to identify mysterious stains, in a library studio at the University of Pennsylvania.

Harry Potter and a basilisk

The weathered, red-leather volume, its cover studded with nails in the shape of a six-pointed star, looks like something from a sorcerer's lair.

At the Science History Institute — the Philadelphia museum and research institution formerly called the Chemical Heritage Foundation — librarians jokingly call it the Harry Potter book.

They are not simply judging the 600-year-old book by its cover. Along with recipes for distilling wine and making black hair dye, the manuscript contains instructions for conjuring up a basilisk — the mythical serpent that played a memorable role in one of J.K. Rowling's best-selling books.

At least it used to contain the basilisk instructions. They are listed in the table of contents but — Merlin's beard! — the pages are missing. Voldemort, anyone?

Connelly and her fellow stain-hunters were not interested in basilisks one day last November. Instead, their sights were trained on a curious blob in the middle of page 68.

They were joined by imaging consultant Michael B. Toth, who had lugged 60 pounds' worth of gadgetry from his office in Oakton, Va.

The technique that he and the stain sleuths used is called multi-spectral imaging — illuminating each page with brief bursts of colored light at a series of very precise wavelengths, then capturing the reflected results with a massive, 60-megapixel camera.

University of Wisconsin researcher Heather Wacha, left, and Erin Connelly, a post-doctoral fellow at Penn’s Schoenberg Institute for Manuscript Studies, look over an 800-year-old manuscript that has mysterious stains.
MICHAEL BRYANT / STAFF PHOTOGRAPHER
University of Wisconsin researcher Heather Wacha, left, and Erin Connelly, a post-doctoral fellow at Penn’s Schoenberg Institute for Manuscript Studies, look over an 800-year-old manuscript that has mysterious stains.

Toth has previously used this technology to reveal "undertext" and other hidden details on ancient manuscripts. He has used it on drafts of the Gettysburg Address, priceless tomes in the Vatican, and an early copy of the Quran. It is almost like Photoshop on steroids, enabling the skilled technician to highlight traces of ink that are scarcely visible to the naked eye.

Here's how the technique can help to identify stains. The key is to have points of comparison. A particular chemical substance reflects the various wavelengths of light emitted from Toth's equipment in very specific ways, yielding a spectral fingerprint. So if the fingerprint of some unknown substance matches the characteristics of a known substance, in theory they are the same substance.

Spectral signatures

Someone turned out the lights in a small studio at Penn's Van Pelt-Dietrich Library. Alberto Campagnolo, a postdoctoral fellow from the Library of Congress, sat at a computer keyboard while Connelly, Toth, and Heather Wacha, a team member from the University of Wisconsin, looked on.

The stained page of the Harry Potter book was bathed in a series of wavelengths of light, one by one: ultraviolet, several shades of blue, green, amber, red, infrared.

With each flash of light, a computer recorded a hard drive's worth of data for later analysis.

The 500-year-old medical text — the one prescribing rabbit bones and ox tongue — also took its turn. The recipes were written out in ink by an Italian scholar named Nola, but on page after page, much of his careful handiwork was obscured by the mysterious stain.

"It could have heavy metals in it," said Connelly, who also analyzes medieval writings for medicinal ingredients that might be useful by modern physicians. "We're just not sure."

Over the course of several weeks, the team would scan manuscripts from five institutions: Penn, the Science History Institute, the Universities of Wisconsin and Iowa, and the Library of Congress. The effort was funded by the nonprofit Council on Library and Information Resources and the Andrew W. Mellon Foundation.

Many of the volumes came from the realms of medicine or alchemy — a term that was interchangeable with the word chemistry in 16th-century Europe, said James Voelkel, curator of rare books at the Science History Institute.

To modern scientists and physicians, these early efforts at mixing odd ingredients are seen as little more than superstition. But the authors were very much the scientists of their day, experimenting by trial and error and sometimes making lasting contributions, Voelkel said.

The Harry Potter book, after all, contains legitimate instructions for distilling wine — along with other recipes that definitely do not work. One claims to transmute lead into gold.

The stained cover of a 500-year-old medical manuscript that was scanned at Penn’s Van Pelt-Dietrich library.
MICHAEL BRYANT / STAFF PHOTOGRAPHER
The stained cover of a 500-year-old medical manuscript that was scanned at Penn’s Van Pelt-Dietrich library.

Fanciful or not, preliminary results from the stain sleuths support the notion that these volumes were heavily used tools of their trades and not just pretty objects on a monastery shelf.

The spectral signature of the stains on Penn's 500-year-old medical text, for example, did not match any of the inks that Nola used to write it. Nor did the stains appear to be the result of mold. So could they be traces from early medicines?

The next step: Create a series of stain samples with ingredients that were known to be used centuries ago — herbs, acids, metals, wine, animal urine — and see if their spectral fingerprints match those from the stains on the old manuscripts. (The blob on the Harry Potter book, meanwhile, turned out to have a more prosaic origin. The scanning data suggested it was merely one of the inks used by the manuscript author.)

Other methods could be used to identify chemical substances on the old pages, Toth said. But some would require the destruction of a small sample of parchment, while others would require advanced expertise, long periods of time, or both.

The advantage of the imaging technology is that each page can be scanned in minutes, and non-scientists can be trained to analyze the resulting data, he said.

All of the data from the stain project will be made public. Toth likes that concept, and not just for altruistic reasons. It means the priceless manuscripts can be downloaded, and preserved, by researchers around the world.

"It used to be you locked your books in a library," Toth said. "You didn't want them stolen. Now, if there's a virus, or a server goes down, or a file is corrupted, it's going to be somewhere else."

And it means others can build upon the initial results in ways that may not have occurred to Connelly and her team members.

Bringing a basilisk to life, maybe not. But with the high-tech scanning contraption, these researchers have brought new life to old stains.

Translation of ingredients in Italian was provided by Eva Del Soldato, an assistant professor of Romance languages at Penn. To learn more about these early efforts at science, visit the new Age of Alchemy exhibition of scientific instruments and paintings at the Science History Institute, 315 Chestnut St. Free admission, open Tuesdays through Saturdays from 10 a.m. to 5 p.m.