WHAT WAS PHYSICS LIKE slightly more than half a century ago? One readily thinks of such famous names as J. J. Thomson, Ernest Rutherford, Marie Curie, Max Planck, Niels Bohr, H. A. Lorentz, Albert Einstein, et al., but these are the highlights of hindsight. For the background of perhaps lesser, but nevertheless significant and interesting efforts, we usually must look to the contemporary literature, since histories of science rarely have room for elaborate descriptions of a period.
During 1910, the physicist Hantaro Nagaoka represented Japan at two international scientific congresses in Brussels and one in Vienna. This visit to Europe gave him an opportunity to observe the latest researches in the various centers of physics and to renew many acquaintances from his student days in Germany. He called at Manchester before continuing to the continent, and the letter he later wrote to Rutherford is both a description of the state of physics through the eyes of an acute observer and a “thank you” to Rutherford.