Jackson received the required permission, and started off at once by a secluded road, keeping Fitz Hugh Lee's brigade of cavalry between his column and the Union army to shield his march from observation.
At 2 A.M., Hooker sent orders for the First Corps, under Reynolds, to which I belonged, to take up its bridges and join him by way of United States Ford, and by 9 A.M.we were on our way.
The first sound of battle came from some guns posted on the eminence from which Hancock had retreated the day before.

A battery there opened fire on the army trains which had been parked in the open plain in front of the Chancellorsville House, and drove them pell mell to the rear.
At dawn Hooker rode around, accompanied by Sickles, to inspect his lines.

He approved the position generally, but upon Sickles' recommendation he threw in a division of the Third Corps between the Eleventh and Twelfth, as he thought the interval too great there.
As soon as Jackson was en route, Lee began to demonstrate against our centre and left, to make Hooker believe the main attack was to be there, and to prevent him from observing the turning column in its progress toward the right.

A vigorous cannonade began against Meade, and a musketry fire was opened on Couch and Slocum; the heaviest attack being on Hancock's position, which was in advance of the main line.
In spite of every precaution, Jackson's column as it moved southward was seen to pass over a bare hill about a mile and a half from Birney's front, and its numbers were pretty accurately estimated.
General Birney at once reported this important fact at General Hooker's headquarters.

It is always pleasant to think your adversary is beaten, and Hooker thought at first Jackson might be retreating on Gordonsville.