1. A MAGNETICALLY CONTROLLED SWITCHING DEVICE COMPRISING AT LEAST A PAIR OF CONTACT MEMBERS EACH HAVING A CONTACT SURFACE ADJACENT TO A MATING CONTACT SURFACE OF THE OTHER SAID MEMBER; BIASING MEANS INDIVIDUAL TO SAID MEMBERS FOR CAUSING A FIRST FLUX TO FLOW THROUGH SAID MEMBERS; IN THE SAME DIRECTION; FLUID GUIDE MEANS FOR DIRECTING A SECOND MAGNETIC FLUX TO SAID ADJACENT CONTACT SURFACES; FIRST CONTROL MEANS MAGNETICALLY COUPLED TO SAID GUIDE MEANS AND EFFECTIVE WHEN ONLY ONE OF SAID BIASING MEANS IS ENERGIZED FOR CAUSING A SECOND FLUX TO FLOW ALONG SAID GUIDE AND THROUGH SAID MEMBERS IN OPPOSITE DIRECTIONS TO OVERCOME SAID FIRST FLUX AND TO INHIBIT THE MATING OF SAID CONTACT SURFACES; AND SECOND CONTROL MEANS MAGNETICALLY COUPLED TO SAID GUIDE MEANS AND EFFECTIVE WHEN BOTH SAID BIASING MEANS ARE CONCURRENTLY ENERGIZED FOR CAUSING A THIRD FLUX WHICH IN VECTORIAL ADDITION WITH SAID SECOND FLUX PRODUCES SUBSTANTIALLY ZERO FLUX FLOW ALONG SAID GUIDE TO SAID ADJACENT CONTACT SURFACES ENABLING SAID SURFACES TO MATE UNDER CONTROL OF SAID FIRST FLUX.