Righi, Augusto. [Extract from letter to Sir Oliver Lodge from Professor Righi of Bologna], 18th June 1897. - 1897. - 1 21 x 13 cm. sheet ; Subjects--Personal Names: Hertz, Heinrich, 1857-1894. Marconi, Guglielmo, 1874-1937 Subjects--Topical Terms: Coherer.