The Union army had been numerous enough to outflank him.
Dick was quite sure of success now.

They had lost two of the most precious of all days instead of one, but they had closed the gap on the north, through which Lee's army might march in an attempt to escape.

It was likely, too, that the last of Jackson's men would come that way and the Union force would cut them off from Lee.

Two entire army corps were now beyond the Antietam, and they should be able to do anything.
The Winchester regiment lay in deep woods, and the great division although it had rested nearly all the day was quiet in the night.

But some ardent souls could not rest.