one o'clock
The guns opened at the crack of day . For seven hours the waves of blood ebbed and flowed . At noon there was a lull . At one o'clock a puff of white smoke flashed from Seminary Ridge . The signal of the men in gray had pealed its death call . Along two miles on this crest they had planted a hundred and fifty guns . Suddenly two miles of flame burst from the hills in a single fiery wreath .