The Black Inventor Who Made Bell's Phone & Edison's Bulb Work The incredible untold story of Lewis Latimer - son of escaped slaves who saved both the telephone AND the light bulb! In 1876, he worked all night to file Bell's telephone patent just hours before a rival, then revolutionized Edison's failing light bulbs with durable carbon filaments that lasted weeks instead of days. Edison was so impressed he hired Latimer as his chief patent investigator and made him the only Black member of the el