French inventor (1844–1940) primarily known for his involvement in wireless telegraphy. ALS in French, signed “E. Branly,” one page, 4.5 x 6, January 23, 1929. Untranslated letter to “Monsieur Claude.” Accompanied by the original mailing envelope. In fine condition, with paper loss along left edge and some scattered mild toning. RR Auction COA.
