As Dick and his young comrades lay down to sleep this march, the greatest of Stonewall Jackson's famous turning movements, had begun already. Jackson was on his horse, Little Sorrel, his old slouch hat drawn down over his eyes, his head bent forward a little, and the great brain thinking, always thinking. His face was turned to the North. Just a little behind Jackson rode one of his most trusted aides, Harry Kenton, a mere youth in years, but already a veteran in service. Not far away was the gallant young Sherburne at the head of his troop of cavalry, and in the first brigade was the regiment of the Invincibles led by Colonel Leonidas Talbot and Lieutenant Colonel Hector St. Hilaire. Never had the two colonels seemed more prim and precise, and not even in youth had the fire of battle ever burned more brightly in their bosoms. Jackson meant to pass around his enemy's right, crossing the Bull Run Mountain at Thoroughfare Gap, then strike the railway in Pope's rear. Longstreet, one of the heaviest hitters of the South, meanwhile was to worry Pope incessantly along the line of the Rappahannock, and when Jackson attacked they were to drive him toward the northeast and away from McClellan. The hot August night was one of the most momentous in American history, and the next few days were to see the Union in greater danger than it has ever stood either before or since. Perhaps it was not given to the actors in the drama to know it then, but the retrospect shows it now. The North had not attained its full fighting strength, and the genius of the two great Southern commanders was at the zenith, while behind them stood a group of generals, full of talent and fearless of death. Jackson had been directly before Sulphur Springs where Dick lay with the division to which he belonged. But Jackson, under cover of the darkness, had slipped away and the division of Longstreet had taken its place so quietly that the Union scouts and spies, including Shepard himself, did not know the difference. Jackson's army marched swiftly and silently, while that of Pope slept. The plan of Lee was complicated and delicate to the last degree, but Jackson, the mainspring in this organism, never doubted that he could carry it out. His division soon left the rest of the army far behind, as they marched steadily on over the hills, the fate of the nation almost in the hollow of their hands.