In 1939, Schiff published a paper that was prompted by a “question in General Relativity” posed to him by Oppenheimer about the properties of the magnetic field he would observe from a circular orbit outside a pair of oppositely rotating, uniformly electrically charged, uniformly rotating, concentric spherically shells of different radii, where both orbit and shells had the same origin in an inertial frame and rotated about the same axis through the origin. Schiff resorts to Mach’s principle in his response. His resolution to a “paradox” posed by Oppenheimer appears cryptic in places and has since led to a number of alternative expositions in the literature, few of which are mutually consistent. In Sect. 33.1 of Chap. 33 we analyse Schiff’s arguments and in Sect. 33.2 offer a reformulation of the rotating 2-shell problem from the perspective of a Maxwell-Minkowski paradigm in which Einsteinian gravitation plays no role. It concludes that, while there is no paradox, an exact analytic solution to a well-posed charged, rotating 2-shell problem is elusive.