The army must either advance or retire; information which had just reached the Confederate general rendered one of these two proceedings indispensable.

The information referred to had been obtained by General Stuart.

The activity and energy of this officer, especially in gaining intelligence, now proved, as they proved often afterward, of the utmost importance to Lee.

Stuart had been directed by General Lee to make an attack, with a cavalry force, on the Orange and Alexandria Railroad, in the enemy's rear; he had promptly carried out his orders by striking the Federal communications at Catlett's Station, had destroyed there all that he found, and torn up the railroad, but, better than all, had captured a box containing official papers belonging to General Pope.

These papers, which Stuart hastened--marching day and night, through storm and flood--to convey to General Lee, presented the clearest evidence of the enemy's movements and designs.