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Claim 1

AN APPARTUS COMPRISING, IN COMBINATION; AN ADAPTER SECTION, A BODY SECTION AND AN INTERMEDIATE VALVE SECTION INTERPOSED WITHIN AND BETWEN SAID ADAPTER AND SAID BODY, SAID ADAPTER SECTION HAVING AN INLET PASSAGE TO SAID INTERMEDIATE VALVE SECTION AND AN OUTLET PASSAGE FROM SAID VALVE SECTION, SAID BODY SECTION COMPRISING TWO PAIRS OF BREAKER PLATES, TWO SCREEN PACKS EACH OF WHICH IS SUPPORTED BETWEN THE BREAKER PLATES OF A PAIR OF SAID TWO PAIRS OF BREAKER PLATES AND INDEPENDENT MEANS FOR ACCESS AND CHAING SAID SCREEN PACKS, SAID BODY SECTION HAVING A PAIR OF INDEPENDENT FLOW INLET PASSAGES FROM SAID VALVE SECTION TO SAID SCREENS PACKS AND A PAIR OF INDEPENDENT FLOW OUTLET PASSAGES FROM SAID SCREEN PACKS TO SAID VALVE SECTION, SAID VALVE SECTION COMPRISING A SINGLE VALVE BODY HAVING A VALVE INLET PORT IN COMMUNICATING RELATIONSHIP WITH SAID ADAPTER INLET PASSAGE, A VAVLE OUTLET PORT IN COMMUNICATING RELATIONSHIP WITH SAID ADAPTER OUTLET PASSAGE, TWO VALVE OUTLET PORTS IN COMMUNICATING RELATIONSHIP WITH SAID BODY FLOW INLET PASSAGES AND AND TWO VALVE INLET PORTS IN COMMUNICATING RELATIONSHIP WITH SAID BODY FLOW OUTLET PASSAGES; A VALVE STEM JOURNALED THEREIN, SAID STEM HAVING (1) TWO ESSENTIALLY DUPLICATE, SIMILARLY ORIENTED, AXIALLY DISPLACED TRANSVERSE INLET AND OUTLET SLOTS, (2) AN AXIALLY DISPLACED DUMP SLOT DIAMETRICALLY OPPOSITE SAID INLET SLOT WHICH EXTENDS AXIALLY INTERMEDIATE SAID INLET SLOT AND OUTLET SLOT AND WHICH IS ADAPTED TO COMMUNICATE WITH AN ATMOSPHERIC DRAIN, AND (3) A BYPASS HOLE, ESSENTIALLY PARALLEL TO AND IN THE SAME TRANSVERSE PLANE AS SAID OUTLET SLOT, SAID INLET SLOT BEING IN THE SAME TRANSVERSE PLANE AS SAID VALVE INLET PORT AND SAID TWO VALVE OUTLET PORTS AND SAID OUTLET SLOT BEING IN THE SAME TRANSVERSE PLANE AS SAID VALVE OUTLET PORT AND SAID TWO VALVE INLET PORTS; AND MEANS FOR ROTATING SAID STEM