1. A RELAY OPERATING BY ELECTROCAPILLARITY, CHARACTERISED IN THAT IT COMPRISES, IN A COMPLETELY CLOSED DUCT, AN ELECTROLYTE SEPARATED FROM AN INSULATING LIQUID BY TWO FLEXIBLE PARTITIONS, TWO ELECTRODES IN THE SAID ELECTROLYTE, AN INSULATING PARTITION DISPOSED BETWEEN THE TWO ELECTRODES AND FORMED WITH A LARGE NUMBER OF CAPILLARY PASSAGES EACH CONTAINING A BEAD OF MERCURY MOVABLE BY ELECTROCAPILLARITY IN THE DIRECTION OF EITHER OF THE FLEXIBLE PARTITIONS, CONTACTS SITUATED WITHIN THE INSULATING LIQUID IN TWO EN-