1. A CABLE RELAY OF RELATIVELY LARGE POWER HANDLING CAPABILITY COMPRISING: A PAIR OF FIXED CONTACTS ATTACHED RESPECTIVELY TO AND SUPPORTED BY A PAIR OF SPACED APART COLLINEAR ELECTRICAL CABLE ENDS AND PROVIDED WITH ENGAGEABLE CONTACT SURFACES AT THEIR ADJACENT ENDS, A SHORTING BAR ADAPTED TO ENGAGE SAID CONTACT SURFACES FOR COMPLETING AN ELECTRICAL CIRCUIT THROUGH SAID FIXED CONTACTS, REMOTELY ACTUATED MEANS FOR MOVING SAID SHORTING BAR INTO SUBSTANTIALLY SIMULTANEOUS ENGAGEMENT WITH SAID CONTACT SURFACES FOR CONNECTING SAID FIXED CONTACTS IN RESPONSE TO REMOTE ACTUATION OF SAID LAST MENTIONED MEANS, A VACUUMIZED ENVELOPE SUPORTED ON SAID COLLINEAR ELECTRICAL CABLE ENDS AND ENCLOSING SAID SHORTING BAR AND THE ADJACENT ENDS OF SAID FIXED CONTACTS, AND MEANS WITHIN THE ENVELOPE TO EFFECT DISENGAGEMENT OF THE SHORTING BAR FROM THE FIXED CONTACTS UPON DEENERGIZATION OF SAID REMOTELY ACTUATED MEANS.