Back in the 1910s and 1920s, Victor Appleton wrote a series of books for boys which featured Tom Swift. In one of them, "Tom Swift and the Caves of Ice" I think it was, Tom uses a new invention in which some small batteries are placed in a tube with an electric bulb and a reflector and lens at one end. A switch then allows the user to turn the electric torch on and off. It was amazing. But a lot of that stuff was just science fiction, eh?