California

The American 19th century entrepreneur Thomas Edison is perhaps most famous for his development of the incandescent light bulb, but few people likely know that part of his inspiration came from an obscure fellow inventor in Connecticut named William Wallace. Edison visited Wallace’s workshop on September 8, 1878, to check out the latter’s prototype “arc light” system. Edison was impressed, but he thought he could improve on the system, which used a steam-powered dynamo to produce an incredibly bright light—much too bright for household use, more akin to outdoor floodlights. The result was the gentle glow of the incandescent bulb.