For the first two decades of his scientific career, Wilhelm Conrad Röntgen (1845-1923) studied a fairly diverse variety of topics, including the specific heats of gases, the Faraday effect in gases, magnetic effects associated with dielectric materials, and the compressibility of water. He is most famous, however, for his discovery in 1895 of X rays, which had a revolutionary effect not only on physics but also on a number of other areas, particularly medicine, and for this he was awarded the first Nobel Prize in physics in 1901.

Wilhelm Conrad Röntgen was born in Lennep, Germany, on March 27, 1845. He was the only child of Friedrich Conrad Röntgen and the former Charlotte Frowein. His father was a textile merchant who came from a long line of metal workers and cloth merchants. His mother had been born in Lennep but then moved with her family to...