POPOV, Aleksandr Stepanovich (1859-1906). Pribor dlia obnaruzhenia i registrirovania elektricheskikh kolebanii [An Apparatus for Detecting and Recording Electrical Oscillations] [dropped-head title], extracted from: Zhurnal russkago fisiko-kimicheskago obshchestva volume XXVIII, part 1. St Petersburg: V. Demakov, 1896.
8° (223 x 151mm). Volume XXVIII, part 1 title and contents leaves, pp.1-14 and part 1, section 1 contents and section 2 resumé leaf. Diagrammatic illustrations. (A few ink-marks, neatly repaired marginal tears on leaves 1/1-7, that on 1/1 slightly affecting text, final leaf on guard.) Modern synthetic leather gilt, titled in gilt on the upper cover, printed wrappers for volume XXVIII, part 7 with advertisement for part 1 dated 28 February 1896 listing Popov's article bound in (wrappers slightly marked). Provenance: early correction in pencil on p.11.
FIRST EDITION. THE FIRST PUBLISHED ACCOUNT OF A COMMERCIALLY PRACTICAL RADIO RECEIVER, which predates published reports of Marconi's experiments. After studying physics and mathematics at St Petersburg University, Popov became a lecturer at the naval Torpedo School at Kronstadt, which provided opportunities for experimental electrical research that the universities could not offer. Following Hertz's discovery of the possibility of transmitting electromagnetic waves, Popov became interested in the subject, using the coherer (a device to detect electromagnetic waves) designed by Oliver Lodge. Lodge's coherer was a tube containing loosely packed metallic powder which, once activated, needed to be agitated to re-form the powder, before it could detect the next signal. Pavlov designed an apparatus which would ring an electric bell once a signal was received: the spring-loaded hammer would strike the bell, and as it returned would strike the coherer and agitate the powder, resetting it to receive the next signal. This apparatus is described in the present article (which illustrates the electrical circuit on p. 8), published in January 1896. Thus, the continuous reception of signals -- and hence practical radio communication -- was possible, and 'by the beginning of 1896 Popov had substantially improved his receiver and had obtained important results in transmitting and receiving signals' (DSB XI, p.93). Quite separately, Marconi had been pursuing similar techniques in the West, and in June 1896 submitted the patent-application for his radio apparatus. The patent was granted in 1897, and the published diagram of his apparatus shows clear similarities to Popov's. Since that time, the question of who first invented a practical radio communications system has remained unresolved: Marconi's claim is generally accepted in the West (but undermined by the lack of published evidence), and Popov's in Russia.