On 7 May 1895, Popov presented the paper ""On the Relation of Metallic Powders to Electric Oscillations"", which described his lightning detector, to the Russian Physical and Chemical Society in St. Petersburg. Most Eastern sources regard Popov's lightning detector as the first radio receiver, and the 7th of May has been celebrated since 1945 in the Russian Federation as "Radio Day". However, there is no evidence Popov sent any type of message on that occasion. The first account of "communication" by Popov was a demonstration on 24 March 1896 at the Physical and Chemical Society, when some accounts say the Morse code message "ГЕНРИХ ГЕРЦ" ("HEINRICH HERTZ" in Russian) was received from a transmitter 250 meters away and transcribed on the blackboard by the Society president. Historian Charles Susskind in 1962 concluded that Popov did not use radio waves for actual wireless communication before mid-1896.