August 10, 2023
Eighteen years before anyone understood what an electron was or that they existed, back when the current was thought to be an incompressible fluid, Edwin Hall, while working on his dissertation, discovered that when applying a current along a thin gold leaf attached to a glass slide, there was no voltage read perpendicular to the current. Still, when the gold leaf slide was placed between the poles of a magnet, a transverse voltage appeared. He believed this phenomenon to be a new electromotiveT...