From 1757 to 1775, Ben Franklin lived in an elegant four-story Georgian house at No. 36 Craven Street in London during his time as an ambassador for the American colonies. In late 1998, a group calling itself Friends of Benjamin Franklin House began to convert the dilapidated building into a museum to honor Franklin, whose other home in Philadelphia had been razed in 1812 to make way for new construction (a "ghost house" frame now sits on the site).

One month into the renovations, a construction worker named Jim Field was working in the basement when he found something odd: a small pit was in a windowless basement room. Inside, sticking out of the dirt floor, was a human thigh bone.

The police were called and supervised excavation continued. More human bones were pulled up. And more. And more, until some 1,200 pieces of bone were recovered. Initial examinations revealed that the bones were the remains of 10 bodies, six of them children, and were a little more than 200 years old. Their age discouraged any interest from Scotland Yard, but piqued the curiosity of historians and the Institute of Archaeology. The bones' age meant they may have been buried in the basement around the same time that Franklin was living in the house.

The Doctor Did It

Did America put a serial killer on the $100 bill? Almost certainly not. Continued study of the bones revealed that some of the bones had been sawed through. Others bore the marks of a scalpel. A few of the skulls had been drilled into. The evidence pointed not to murder by Franklin, but anatomical study by his friend William Hewson.

Hewson had been a student of the anatomist William Hunter until the two had a falling out and Hewson broke away to continue his studies on his own. Anatomy was still in its infancy, but the day's social and ethical mores frowned upon it. Dissection of human bodies was prohibited by law A steady supply of human bodies was hard to come by legally, so Hewson, Hunter, and the field’s other pioneers had to turn to grave robbing — either paying professional “resurrection men” to procure cadavers or digging them up themselves — to get their hands on specimens.

Researchers think that 36 Craven was an irresistible spot for Hewson to establish his own anatomy lab. The tenant was a trusted friend, the landlady was his mother-in-law, and he was flanked by convenient sources for corpses. Bodies could be smuggled from graveyards and delivered to the wharf at one end of the street, or snatched from the gallows at the other end. When he was done with them, Hewson simply buried whatever was left of the bodies in the basement, rather than sneak them out for disposal elsewhere and risk getting caught and prosecuted for dissection and grave robbing.

How involved was Franklin, then? No one knows for sure. As far as the Friends of Benjamin Franklin House will speculate, Franklin could have known what was going in the house, but didn’t participate. He was, after all, more interested in physics than medicine. It’s also possible that he wasn’t using the house during the dissections and had no idea this was happening. The Friends have found some evidence that Franklin let Hewson have use of the whole house for a while and lived up the street with the landlady during that time.

The year Franklin left England and returned to North America, Hewson fell victim to his scientific pursuits, accidentally cutting himself while dissecting a putrid body and dying from an infection.

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