Obituary

Michael Idvorsky Pupin (A´90, F´15, HM´28, past-president and member for life) professor emeritus in active residence, Columbia University, New York, N. Y., died March 12, 1935. One of the leading scientists at the time of his death, he came to the United States in 1874 as a penniless boy intent on securing a higher education, but whose first job was driving mules for a Delaware farmer. Doctor Pupin was born at Idvor, Banat, Hungary (now in Yugoslavia) October 4, 1858. In 1879 he entered Columbia University, and was graduated with the degree of bachelor of arts in 1883. He afterward studied mathematics at the University of Cambridge, England, and physics at the University of Berlin, Germany, holding while in Berlin the John Tyndall fellowship of Columbia University. After receiving the degree of doctor of philosophy at Berlin in 1889 he became instructor of mathematical physics at Columbia University, and adjunct professor of mechanics in 1892. In 1901 he was appointed professor of electromechanics, and 2 years later director of the Phoenix Research Laboratory of Columbia University, a position which he held until he retired from active service in 1929. Doctor Pupin made important contributions to knowledge in a-c theory, the passage of electricity through gases, long distance communication, and other subjcts. In a paper published in 1896 he first described the nature of secondary X ray radiation, and in 1902 he sold patents covering his inventions in electrical tuning, so important in radio broadcasting, to the Marconi Company. Previous to this he had accomplished the rectification of high frequency electrical waves, the description being published in 1899. Rapid X ray photography by the use of a fluorescent screen was invented and described by Doctor Pupin in 1896. The chief invention credited to him is the principle of loading telephone or telegraph lines by lumped inductance, his “loading coils” compensating by their inductance for the capaci- ance between the 2 wires of the circuit. Doctor Pupin also proposed a rule for the placement of these inductances along the line. In this way transmission over long open wire or cable lines was greatly improved. Doctor Pupin received numerous honors for his work, and was awarded some 18 honorary degrees. Among the medals he received are the Cresson medal of the Franklin Institute, 1902; the Prix Herbert of the French Academy, 1916; the medal of the Institute of Radio Engineers, 1924; the Edison medal of the Institute, 1925; and the John Fritz medal, 1932. Doctor Pupin was a past-president of the Institute of Radio Engineers, a past-chairman of the Engineering Foundation, and a member of many other societies. He was a manager of the Institute, 1892–95, a vice president, 1895–97 and 1901–03, and president, 1925–26, in addition serving on a number of Institute committees. Several books and numerous papers have been written by him, many of his papers having been presented before the Institute.