An early German cathode tube design. The owner of this tube could float free and alive in the air, without wings, and see through metal cabinets to read the secret papers stacked in coherent layers, inside. However, once this skill became common and available to all, it lost a lot of its cache. Now, flying people with xray eyes are considered a bit boorish.     Spinning disks scanned mourners left behind by the dead, changing their pictures to sounds, which were transmitted through telephone wires.