As far as medical mysteries go, they don't get much bigger than that of "Dr. Anonymous," a mystery that spans two centuries and includes some the biggest names in the history of medicine. This mystery's final unraveling, by a cardiologist at Weill Cornell Medical College, was the result of a quarter-century of historical research, and not just a bit of luck.

"The strange case of 'Dr. Anonymous' is a tale of discovery, of medical history, of bibliomania and serendipity," said Dr. Paul Kligfield, who told how he solved the mystery in a lecture of the Heberden Society at Weill Cornell in New York City Oct. 22.

The tale begins with William Heberden himself, the namesake of the society, a London physician who was among the most famous of the late 18th century. In 1772 Heberden published "Some Account of the Disorder of the Breast" in the Medical Transactions of the College of Physicians of London. Heberden's description of angina pectoris, or heart attack, was the first in the history of medicine, and it was so well written that subsequent historians have described it as "the most concise and precise original description of disease in the history of medicine."

Soon thereafter, Heberden received an anonymous letter that described the correspondent's own chest pain in extraordinary detail. (It was so clear that Kligfield can diagnose it today -- ventricular arrhythmia with postextrasystolic potentiation.) The anonymous author expressed fear that he would soon die suddenly and offered his body to Heberden for autopsy.

Indeed, three weeks later, the correspondent died; his will requested that Herberden be notified. Heberden later reported the results of the autopsy by a local physician in Medical Transactions in 1785.

Over the next 200 years, scholars unearthing the history of cardiology and heart attack speculated about who the anonymous correspondent -- who became known as "Dr. Anonymous" -- might have been. Guesses abounded, but no one could definitively identify the person.

That was until 1982, when Kligfield serendipitously found a first edition copy of Medical Transactions, which included a reprint of the entire Heberden-"Dr. Anonymous" correspondence, while he was nosing around a bookshop in London.

Under the closing salutation "Unknown" in this particular copy of Medical Transactions, "Mallet/formerly of Exeter" was neatly written in an 18th-century hand. Looking deeper, Kligfield searched the obituaries of The London Evening Post for a Mallet who had died three weeks after the date of the original letter.

Sure enough, the May 7-9, 1772, edition of the Post listed the death of "Mr. John Mallet, formerly of Exeter, merchant." Eventually, Kligfield tracked Mallet to a cemetery in central London. He also found a 1770 edition of "Baldwin's Complete Guide," essentially a "Who's Who" of 18th-century London, which listed "John Mallet, formerly of Exeter" as a prominent merchant who lived on Aldersgate Street, not far from the cemetery in which he was buried. As Kligfield discovered, it turns out that for all his storied history in the annals of cardiology, "Dr. Anonymous" was no doctor at all.

The Heberden Society was established in 1975 as a means for promoting interest in the history of medicine.

Gabriel Miller is a freelance writer in New York City.