They say not to judge a book by its cover, but that can be difficult when the cover is made of human skin.
Residing on the sixth floor of Van Pelt Library, Bibliotheque Nationale, a catalogue of medical texts published in 1857, is bound in human leather tanned by 1868 Penn Medical School graduate John Stockton Hough.
Though Van Pelt is just one of many prominent libraries on the East Coast -- including Harvard and Brown universities' -- to own a book bound in human leather, the University has an especially strong link to the tanning of human skin.
Though an effort was made to keep this practice from becoming widely known, it was relatively commonplace in the latter half of the nineteenth century, according to a St. Louis Post-Dispatch article from the era tucked between the cover pages of Bibliotheque Nationale.
Because most of those who bound their books in human skin were physicians and Penn had a leading medical school at the time, many human-skin tanners were Penn graduates, according to Laura Hartman. Hartman is a rare-book cataloger at the National Library of Medicine in Maryland and an expert on anthropodermic binding (the slightly more palatable term for human-skin binding).
The tanning was often done in the now-defunct Philadelphia General Hospital, once located at the current site of the Children's Hospital of Philadelphia, just a few blocks off campus.
"There were certainly some Penn-affiliated physicians tanning human leather in the [hospital] basement," Hartman said.
Joseph Leidy, for whom the Leidy Laboratories of Biology are named, was a professor of anatomy at Penn for over 40 years. He had his seminal work, An Elementary Treatise on Human Anatomy, bound in skin from a soldier who died in the Civil War.
According to Hartman, Leidy was a physician for the Union during the war and the skin likely came from one of his patients.
The use of human leather was not limited to books, though, as many physicians carried their surgical tools in human-skin purses. W. W. Keen, a colleague of Leidy's at Penn, was given a human-skin wallet by one of his pupils as a token of appreciation.
Despite the macabre nature of the practice, Hartman said that it would be wrong to judge 19th-century tanners of human skin harshly. Often, she said, the procedure was performed in tribute to or at the request of the deceased.
There were also practical considerations.
"Human skin, when tanned into leather, is very durable," Hartman said, adding that human leather is more water-resistant than other leathers.
Hough's book, the only of its kind at Penn, is one of at least five he made during his lifetime.
After Hough's death in 1900, his 3,247-book collection was acquired by the College of Physicians of Philadelphia. The college kept about half of the books and sold the rest -- duplicates and non-medical texts -- to Penn.
Considering that Bibliotheque Nationale was a fairly common text, Hartman believes that the book was passed on to Penn because the College of Physicians had another copy.
Though Hough's other anthropodermically bound volumes identify the former owner of the skin with notes scribbled on the cover page, Bibliotheque Nationale does not.
"Bound from skin from the back. Tanned June 1887. Bound, [January] 1888" is all that Hough wrote in the book.
Van Pelt Curator of Printed Books Lynne Farrington said that while every once in a while a visitor asks to see the book, most people do not know it exists.
A few years ago, though, an admissions tour guide caught wind of the book and started telling his tours about it, she said.
Swamped by curious visitors, the library had to call the Admissions Office to ask the tour guide to stop mentioning the book, Farrington said.
"We try not to advertise it because we try not to turn it into a curiosity," she said.
"If somebody had a legitimate reason to use it, that would be fine," she said, adding that it has rarely been used for research.
Penn bioethicist Paul Wolpe agreed, saying that while there is nothing immoral about a library holding an anthropodermically bound book, "it should not be gawked at as a curiosity."
"I don't think the average Joe should be able to take this out, but I think people with a scholarly interest should be," Wolpe added.
He emphasized, though, that with artifacts such as Bibliotheque Nationale, the skin used was not from exploited individuals, such as slaves or concentration-camp prisoners, but often from people of significance to the binder.
Hough, for instance, bound three of his books using skin from a "Mary L," in whom he found the first Philadelphia case of encysted trichinosis, a parasitic infection.
Hartman said that she believes the binding of one of the books, a tome on diseases afflicting women, was a tribute of sorts to his perished patient.
Like Mary L, Hough died prematurely, but not of natural causes.
At the age of 55, he succumbed to injuries received when a runaway horse threw him from his carriage.
No word on what happened to his skin.