A recent discovery at Harvard's Houghton Library might make your skin crawl a bit.

Scientist have confirmed that a 19th century tome by French novelist and poet Arsène Houssaye is bound with human skin. The copy of Houssaye's "Des destinées de l’ame" (Destinies of The Soul) is located in Houghton Library, Harvard's rare-book repository. 

The skin was taken from the back of a female mental patient who died from a stroke, a post on the university’s blog detailed. The use of tanned human skin was a common practice during the 19th century. But the skin typically came from the bodies of executed criminals that were donated for scientific research. 

In order to confirm that the book’s binding was crafted from human skin, microscopic samples were taken from the binding. The samples were analyzed using peptide mass fingerprinting, which is used to identify the proteins used to make a peptide mass fingerprint (PMF). The process lets scientists identify the source of the proteins.   

Researchers said the PMF from the book “clearly eliminated other common parchment sources, such as sheep, cattle and goat.” But according to the team, other primates closely related to humans could not be ruled out as a possible source of the PMF since there’s a “lack of necessary references.”

The statement adds that the samples from the book were also analyzed using Liquid Chromatography-Tandem Mass Spectrometry. This was used to uncover the order of the amino acids in the proteins, which differ among species.

“The analytical data, taken together with the provenance of 'Des destinées de l’ame,' make it very unlikely that the source could be other than human,” said Bill Lane, the director of the Harvard Mass Spectrometry and Proteomics Resource Laboratory.

It book was given as a gift by Houssaye to his doctor friend Ludovic Bouland. It is now recognized as the only known book at Harvard to be bound with human skin. 

In 2006, Harvard's newspaper, The Crimson, reported that there were at least three books in the school's catalog bound in human skin. But after testing the other two volumes, located at the Harvard Law School Library and the Harvard Medical School's Countway Library, it was confirmed they were actually wrapped in sheepskin, reports CNN. 

A book collector first delivered the human skin-bound version of "Des destinees de l'ame" to the Houghton Library in 1934. Twenty years later, following his death, the book was given to the library by his widow.