IT is announced that the Nobel Prize for chemistry for 1934 has been awarded to Prof. H. C. Urey, of Columbia University, New York. Prof. Urey was responsible for the search for a heavier isotope of hydrogen, and for its detection by means of its spectrum. This heavier isotope, of mass about double that of the ordinary hydrogen atom, has since been obtained in the form of its oxide, ‘heavy water’, in a pure condition, and several other compounds, for example, an ammonia in which the three hy drogen atoms are replaced by heavy hydrogen. The new element has been called deuterium, and has been the subject of intensive investigation during the last two years. Unlike the isotopes of heavier ele ments, its properties differ in a marked and interesting way from those of ordinary hydrogen, and apart from its intrinsic interest, deuterium has already been put to several uses as an implement of research in various fields of chemistry and physics. Just as the discovery of the element radium by Mme. Curie, a chemist, opened out a new physics, so it may be expected that the discovery of deuterium by the present Nobel laureate in chemistry will have important conse quences for physics as well as chemistry.