Geiger Counter

   Hans Wilhelm Geiger (1882-1945) introduced the first successful counter of individual alpha rays through an instrument known as the Geiger counter. Geiger was bom at Neustadt-an-der-Hardt, Germany. His father was a prominent rabbi and one of the leaders of Reformed Judaism. The son did not follow in his father's footsteps, but instead elected to pursue the study of science. He attended the universities at Munich and Erlangen, and obtained a doctorate in 1906 for work on electrical discharges in gases. He then took up a position at the University of Manchester, where he worked with Ernest Rutherford from 1907 to 1912. With Rutherford's assistance, Geiger developed an instrument for detecting alpha particles, which became the basis of the modern Geiger counter. He then returned to Germany, where he held important university positions for the rest of his days.

   In association with Wilhelm Miiller, Geiger produced what is now known as the Geiger-Muller counter, a gas-filled counting tube combined with an electronic device capable of reading and measuring the rate of radioactive substances. Ionizing particles penetrate the tube and pulsate the gas; hence the clicking sound.

   The Geiger counter, as it is generally called, is used for prospecting and for locating nuclear radiation. But more important, it is used by physicians to locate malignancies, and in that role has saved manylives.