1. A pulse counting circuit comprising a plurality of static electrical relays, each of said relays comprising a first element having first and second spaced electrodes therein, said first element being initially insulating and becoming conductive upon exposure to heat; a second element coupled to said first element, said second element having a pyrotechnical composition; electrically excited means having third and fourth terminals for initiating the reaction of said second element to produce sufficient heat to cause said first element to become conductive, said first and second spaced electrodes being insulated from each other by said first element prior to initiating the reaction of said second element and being electrically connEcted after exposure of said first element to the heat generated by said second element; means for coupling an input pulse across the third and fourth terminals of the electrical exciting means of a first of said plurality of relays and to the first electrode of the first element of said relay, means coupling the second electrode of the second element of each of said relays to the first electrode and third terminal of a succeeding relay, means coupling the fourth terminal of each succeeding relay to the fourth terminal of the preceding relay, and means for obtaining an output voltage between the second electrode and fourth terminal of each of said plurality of relays.