Michael Idvorsky Pupin received his Columbia College undergraduate degree in 1883 and his PhD at the University of Berlin in 1889, returning to teach at Columbia in 1892. The subject of electrical resonance engaged his attention between 1892 and 1895, and resulted in the electrical tuning which was universally applied in all radio work. In February of 1896, following Wilhelm Roentgen's November 1895 discovery of "new kind of rays," he discovered a rapid method of X-ray photography that used a fluorescent screen between the object to the photographed and the photographic plate. This shortened the exposure time from about an hour to a few seconds, and is the method now in universal use.

In April of that year he discovered that matter struck by X-rays is stimulated to radiate other X-rays (secondary radiation), and invented an electrical resonator. Pupin received 34 patents for his inventions, and won the Pulitzer Prize in 1924 for his autobiography From Immigrant to Inventor. Columbia University's holdings include architectural drawings, blueprints and graphs, photographs, portraits, awards and diplomas. This print of an x-ray photograph, showing lead shot in a human hand, was probably taken in February, 1896.