As darkness falls upon the Wilderness, and the fire of the outposts, provoked by every movement of the patrols, gradually dies away, we may seek the explanation of the Federal movements.  On finding that his enemy, instead of “ingloriously flying,” was advancing to meet him, and advancing with confident and aggressive vigour, Hooker’s resolution had failed him.  Waiting till his force was concentrated, until the Second and Third Corps had crossed at United States Ford, and were close to Chancellorsville, it was not till eleven o’clock on the morning of May 1 that he had marched in three great columns towards Fredericksburg.  His intention was to pass rapidly through the Wilderness, secure the open ground about Tabernacle Church, and there, with ample space for deployment, to form for battle, and move against the rear of Marye’s Hill.* (* O.R. volume 25 page 324.) But before his advanced guards got clear of the forest defiles they found the Confederates across their path, displaying an unmistakable purpose of pressing the attack.  Hooker at once concluded that Lee was marching against him with nearly his whole force, and of the strength of that force, owing to the weakness of his cavalry, he was not aware.  The news from the Stafford Heights was disquieting.  As soon as the fog had lifted, about nine o’clock in the morning, the signal officers and balloonists had descried long columns of troops and trains marching rapidly towards Chancellorsville.* (* O.R. volume 25 pages 323, 336.) This was duly reported by the telegraph,* (* Ibid page 326.  The telegraph, however, appears to have worked badly, and dispatches took several hours to pass from Falmouth to Chancellorsville.) and it was correctly inferred to signify that Lee was concentrating against the Federal right.  But at the same time various movements were observed about Hamilton’s Crossing; columns appeared marching from the direction of Gurney’s Station; there was much traffic on the railway, and several deserters from Lee’s army declared, on being examined, that Hood’s and Pickett’s divisions had arrived from Richmond.* (* Ibid page 327.) The statements of these men—­who we may suspect were not such traitors as they appeared—­were confirmed by the fact that Sedgwick, who was without cavalry, had noticed no diminution in the force which held the ridge before him.

It is easy, then, to understand Hooker’s decision to stand on the defensive.  With a prudent foresight which does him much credit, before he marched in the morning he had ordered the position about Chancellorsville, covering his lines of retreat to United States and Ely’s Fords, to be reconnoitred and intrenched, and his front, as Lee said, was undoubtedly very strong.  He would assuredly have done better had he attacked vigorously when he found the Confederates advancing.  His sudden retrograde movement, especially as following the swift and successful manoeuvres which had turned Lee’s position, could not fail to have a discouraging