ring of fire
131Duquesne Spy Ring — The 33 convicted members of the Duquesne spy ring (FBI print). The Duquesne Spy Ring is the largest espionage case in United States history that ended in convictions. A total of thirty three members of a German espionage network headed by… …
132Toroidal ring model — The toroidal ring model, known originally as the Parson magneton or magnetic electron, is also known as the plasmoid ring, vortex ring, or helicon ring. This physical model treated electrons and protons as elementary particles, and was first… …
