about four o'clock
During the night and the next day the _ Porpoise _ forged on underneath the waves . Washington relieved Mr. Henderson in the conning tower and reported the machinery to be working well . `` Keep her headed due south , '' was the order of the inventor , and the colored man did so . It was about four o'clock one morning that Washington felt a slight jar to the submarine . `` Hope we ai n't goin ' to hit no more battleships , '' he said . He glanced at the speed-indicating gage . To his surprise it stood at zero .