Niels Bohr (1885-1962), Danish physicist and Nobel laureate. Bohr made numerous contributions to physics during his career, but it was his work on the structure of atoms that won him the 1922 Nobel Prize. Following Ernest Rutherford's discovery of the nucleus, Bohr described the atom as a small, positively charged nucleus surrounded by waves of electrons with discrete (quantised) energies. Though associated with the Manhattan Project in World War II, he dedicated his later life to peaceful applications of atomic physics. This portrait is from the Bain News Service, one of America's oldest news picture agencies, which holds images dating from the 1890s to the 1930s.