Sound generator for telephone tests

Philipp Reis was discouraged by a lack of recognition in professional circles. Only in 1872–73 did he return to work on the telephone, when he built a new type of receiver.The "wooden box with attuned small steel rods (music box) with electromagnets for musical telephone experiments" was given to the Berlin Reichspostmuseum, the Imperial Postal Museum, in 1886 as a gift from Léon Garnier from Friedrichsdorf.