"The Quantum Postulate and the Recent Development of Atomic Theory" in "Nature".

Bohr, Niels. "The Quantum Postulate and the Recent Development of Atomic Theory" in "Nature", Macmillan & Co, London, 1928, vol. 121, pp. 580-590, offered in the full volume of 1044, lxiipp, covering January-June, complete. Bound in a very sturdy cloth. Very nice, clean copy. VG  "Complementarity was not an arbitrary creation of Bohr s mind, but the precise expression, won after patient efforts demanding a tremendous concentration, of a state of affairs entirely grounded in nature s laws, one that, according to Bohr s familiar exhortation, had to be learned only from nature. It consecrated the recognition of a statistical from of causality as the only possible link between phenomena presenting quantal individuality, but made it plain that the statistical mode of description of quantum mechanics was perfectly adapted to these phenomena and gave an exhaustive account of all their observable aspects. From the epistemological point of view, the discovery of the new type of logical relationship that complementarity represents is a major advance that radically changes our whole view of the role and meaning of science. In contrast with the nineteenth-century ideal of a description of the phenomena from which every reference to their observation would be eliminated, we now have the much wider and truer prospect of an account of the phenomena in which due regard is paid to the conditions under which they can actually be observed thereby securing the full objectivity of the description, since the description is based on purely physical operations intelligible and verifiable by all observers. The role of the classical concepts in this description is obviously essential, since those concepts are the only ones adapted to our capabilities of observation and unambiguous communication."--Complete DSB online. [++] Also appearing in this volume are three Nobel Prize-producing papers by Raman (with K. S. Krishnan), on pp 501-2; "A Change of Wave-length in Light Scattering" on p. 619; and with Krishnan again, "The Optical Analogue of the Compton Effect", p. 711. ("Raman and K. S. Krishnan then undertook to isolate the effect under impeccable experimental conditions. They employed complementary light filters placed in the paths of the incident and scattered light, respectively, and observed a new type of secondary radiation from the scattering of focused beams of sunlight in both carefully purified liquid and dust-free air. They reported this discovery in a letter to Nature in February 1928. Raman then refined the experiment by using a mercury arc as the source of light; the effect was thus clearly seen for the first time on 28 February 1928 and was reported to the Science Congress at Bangalore the following month."--Complete DSB online.…