PUPIN, MICHAEL IDVORSKY

born Oct. 4, 1858, Idvor, Hung. died March 12, 1935, New York, N.Y., U.S. American physicist who devised a means of greatly extending the range of long-distance telephone communication by placing loading coils (of wire) at predetermined intervals along the transmitting wire. The son of illiterate parents who encouraged his education, Pupin in 1890 became an instructor in mathematical physics at Columbia University, New York City. Six years later he discovered that atoms struck by X rays emit secondary X-ray radiation. He also invented a means for taking short-exposure X-ray photographs. In 1901 the Bell Telephone Company and some German telephone interests acquired the patent for his invention of long-distance telephony. Pupin received the 1924 Pulitzer Prize in biography for his autobiographical work From Immigrant to Inventor (1923).