the hour of four
`` Fifteen minutes more , '' sighed Dal . `` They 'll seem like fifteen years , though , Bob , '' commented Jimmy . A reaction , in the shape of silence , came upon the Khaki Boys -- `` five Brothers '' as they called themselves , for they had become that since their participation in the World War . Tensely and quietly they waited in the trench for the hands of time to move to the hour of four . This was the `` zero '' period , when in a wave of men and steel , or lead and high explosives , the Americans would go over the top , in an endeavor to dislodge the Germans from a strong position . Only a few hours before , after each had written a letter home , the missives having been sent back of the lines to be posted , the five lads had solemnly shaken hands at parting . The two sergeants -- James Blaise and Roger Barlow -- went to a distant part of the intricate trench system , while the two corporals , Robert Dalton and Ignace Pulinski and Sergeant Franz Schnitzel were together in a ditch near the middle of the barbed wire entanglements .