With his own knowledge of chemistry and metallurgy, as well as the help of chemist Paul Beck Goddard, Cornelius attempted to perfect the daguerreotype. Around October 1839, Cornelius took a portrait of himself outside of the family store. In our digital age, self-portraits are literally taken a million times every day. But Robert Cornelius had to stare motionless for over five minutes when he took his own picture. The daguerreotype produced shows an off center portrait of a man with crossed arms and tousled hair. This self-portrait of Robert Cornelius is one of the first photographs of a human to be produced.
|An early self-portrait of inventor and businessman Robert Cornelius, taken in 1839. Image courtesy of the Library of Congress.|
Shortly before he died in 1893, Cornelius told Julius Sachse, a Philadelphia photographer and future editor the American Journal of Photography, that he had taken portraits as early as October, 1839. No corroborating evidence was found until 1975, when Murphy D. Smith, librarian at the American Philosophical Society, found a photograph of Goddard dated on the back December 6, 1839, the date Cornelius and Goddard introduced their invention to the Society.
(via Wikipedia and PA History)