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,