three o'clock
`` Strahan and I had a quiet talk early in the day , and said what we wished to each other . After that he became dreamy and absorbed in his own thoughts as we watched for signs of the enemy through hours that seemed interminable . Some laughing , jesting , and card-playing went on among the men , but in the main they were grave , thoughtful , and alert , spending the time in discussing the probabilities of this conflict , and in recalling scenes of past battles . `` Suddenly -- it could not have been much past three o'clock -- a dozen rebel batteries opened upon us , and in a second we were in a tempest of flying , bursting shells . Our guns , a few yards away , and other batteries along our line , replied . The roar of the opening battle thundered away to the right as far as we could hear . We were formed into line at once , and lay down upon the ground .