When construction crews working in Queens, New York unearthed the remains of a woman clad in a white nightgown and knee-high socks in 2011, the body was so well preserved they nearly thought to call the police for fear she was a recent homicide victim. Her coffin, however, told a different story.
Scott Warnasch, a forensic archaeologist for the city was called to the scene. Warnasch worked at the World Trade Center site after 9/11 and, with 25 years on the job, was experienced in identifying the remains of people lost in time. Metal fragments located near the burial site indicated the woman was buried more than 150 years ago, while an analysis of public census records and her unique 19th-century cast-iron coffin has helped Warnasch identify the 26-year-old African-American woman as Martha Peterson, the daughter of two prominent area figures.
Her coffin was made by a former stove manufacturer Fisk & Raymond who constructed form-fitting iron coffins only used briefly in the mid-1800s. Because wood coffins decompose and leave only bones behind, iron coffins were an expensive alternative only used by the wealthy to preserve the corpses inside unless the person had died from infectious diseases. During a time where airborne illnesses could be fatal, these airtight designs also served a much more practical purpose.

“In addition to transportation and storage, Fisk’s coffins also provided a safe way to quarantine victims of contagious diseases, while still allowing for a traditional funeral and viewing,” Warnasch explained to PBS. “In a time before extensive use of photography, the coffin’s oval glass viewing window allowed next of kin to see and confirm the identity of the occupant without encountering odor or potential diseases. A third selling point was as a deterrent to grave robbers, who stole corpses to sell to medical schools for dissection.”
For years Warnasch and his team studied the remains by conducting a “virtual” autopsy using computer software to determine her cause of death – most likely smallpox. A forensic imaging specialist created a facial reconstruction by using a CT scan of her skull, digitally fixing parts of it that were damaged, and incorporating her age and ancestry features from a database.
After more than five years of examinations, her body was laid to rest in November 2016.
Martha Peterson’s story will be shared in a PBS documentary, Secrets of the Dead: The Woman in the Iron Coffin, available for streaming on its website and app from October 4.
