In meyer documents you can find the tube cell arrangement with two tube sets where the inner tubes are soldered together in a disk. And in this same drawing he describe by little arrows that one outer tube is positive and the other is negative.
If you get to read all the patents that cited meyer and the patents they also cited and so one is easier to understand why meyer talked its about movement and deflection of electrons.
If you remember well physics, Inside a hollow conductor the field is zero, a dielectric don't have moveable electrons, the field outside of a capacitor is zero,
