The Shallows: What the Internet is Doing to Our Brains

by Nicholas Carr

In 1906, his moment arrived. Without quite knowing what he was doing, he took a standard two-pole vacuum tube, which sent an electric current from one wire (the filament) to a second (the plate), and he added a third wire to it, turning the diode into a triode. He found that when he sent a small electric charge into the third wire—the grid—it boosted the strength of the current running between the filament and the plate. The device, he explained in a patent application, could be adapted “for amplifying feeble electric currents.”2 De Forest’s seemingly modest invention turned out to be a world changer. Because it could be used to amplify an electrical signal, it could also be used to amplify audio transmissions sent and received as radio waves. Up to then, radios had been of limited use because their signals faded so quickly. With the Audion to boost the signals, long-distance wireless transmissions became possible, setting the stage for radio broadcasting. The Audion became, as well, a critical component of the new telephone system, enabling people on opposite sides of the country, or the world, to hear each other talk. De Forest couldn’t have known it at the time, but he had inaugurated the age of electronics.