1. AN ELECTRICAL CONNECTOR OF THE TYPE IN WHICH PERMANENT ELECTRICAL CONTINUITY IS ESTABLISHED BETWEEN SPACED ELECTRODES IN RESPONSE TO THE APPLICATION OF HEAT TO FUSIBLE MATERIAL; SAID CONNECTOR COMPRISING A CENTRE ELECTRODE, TWO END ELECTRODES; MEANS SUPPORTING SAID CENTRE AND END ELECTRODES IN SPACED RELATIONSHIP FROM EACH OTHER AND FROM SAID CENTRE ELECTRODE SO AS TO DEFINE A CAVITY; MEANS INSULATING SAID END ELECTRODES FROM SAID CENTRE ELECTRODE; FUSIBLE MATERIAL DISPOSED ON SAID ELECTRODES; RESISTANCE MEANS THERMALLY CONNECTED TO SAID ELECTRODES FOR HEATING SAID FUSIBLE MATERIAL; AND MEANS FOR SUBDIVIDING SAID CAVITY INTO TWO CHAMBERS, EACH CONTAINING FUSIBLE MATERIAL, AND PREVENTING FLOW OF FUSIBLE MATERIAL FROM ONE CHAMBER OF THE OTHER; THE SPACING OF SAID ELECTRODES BEING