"What is it?" someone asked after a brief interval of mystificalion. "Well-this is a pile of glass plates. A beam of sunlight striking the pile at this angle will be partially reflected and partially transmitted. The reflected part will be polarized. Now we adjust the pile to reflect the beam through this thing, which is Brother Kornhoer’s idea, and let the light fall on this second pile of glass plates. The second pile is set at just the right angle to reflect almost all of the polarized beam, and transmit nearly none of it. Looking through the glass, we’d scarcely see the light. All this has been tried. But now if my hypothesis is correct, closing this switch on Brother Kornhoer’s field coil here should cause a sudden brightening of the transmitted light. If it doesn’t-" he shrugged "-then we throw out the hypothesis."