Penn Physicist’s Accidental Images Among earliest Known X-Rays
PHILADELPHIA – The University of Pennsylvania has received a collection of photographic plates containing some of the earliest known X-ray images,created accidentally by Penn physicist Arthur Goodspeed in 1890 – years before Wilhelm Conrad Röntgen‘s groundbreaking work was widely publicized. The images, revealed Tuesday, depict faint shadows created when radiation from a Crookes tube interacted with coins and photographic plates left in a lecture room.
The finding offers a rare glimpse into the nascent stages of radiology and highlights a parallel, largely unknown, exploration of X-ray technology happening concurrently with Röntgen’s celebrated experiments. While Röntgen is credited with discovering X-rays in 1895 and publishing his findings in 1896, Goodspeed’s work demonstrates that similar phenomena were being observed and documented in Philadelphia several years prior.
goodspeed and photographer William Jennings were experimenting with electrical charges to create images of coins and brass weights when the accidental images were created. After their work was complete, they stacked photographic plates and left coins nearby.Goodspeed then demonstrated Crookes tubes - glass cylinders used to study cathode rays – to jennings. Unbeknownst to them, the radiation emitted from the tube exposed the photographic plates, creating the mysterious shadows.
“He knew something happened and ‘I might want to look at this someday’ sort of thing,” said University Archivist John Bence, referring to Goodspeed’s decision to preserve the images.
At the time, the scientists couldn’t explain the markings.Simultaneously occurring, Röntgen, in Germany, was intentionally experimenting with crookes tubes and electric currents, ultimately developing a method to capture images of objects based on their differing densities. His famous 1895 image of his wife’s hand, revealing her bones and a ring, became iconic.
The newly donated images underscore the complex history of scientific discovery and the frequently enough-unforeseen paths that lead to major breakthroughs.The collection will be preserved by the University Archives and made available for research and educational purposes.
