While several scientists, including Joseph Swan and Thomas Edison, have claims on the invention of the incandescent light bulb, there’s no doubt this magic lamp that produced clean, odourless light at the flick of a switch brought the world into the ‘electric’ age. But in 1906, U.S. scientist Lee De Forest added extra connections or ‘electrodes’ to the light bulb - he then found that a weak voltage applied to one electrode could control the flow of a much larger current through two others. This discovery, later dubbed the ‘triode’, launched the world into the ‘electronic’ age. Despite thermionic valves (or ‘vacuum tubes’ in the U.S.) having been superseded for more than 50
