These works would double the Confederate strength in case of battle in front of them; and, believing himself already outnumbered, the Federal commander was naturally loath to deliver battle until reenforced.

The faulty disposition of his army, divided by a stream crossed by few bridges, has been accounted for in like manner--he so disposed the troops, expecting reenforcements.

But Jackson's energy delayed these.
Washington was in danger, it was supposed, and General McDowell did not come.

It thus happened that General McClellan awaited attack instead of making it, and that his army was so posted as to expose him to the greatest peril.
A last point is to be noted in vindication of this able soldier.
Finding, at the very last moment, that he could expect no further assistance from the President or General Halleck, he resolved promptly to withdraw his exposed right wing and change his base of operations to James River, where at least his communications would be safe.

This, it seems, had been determined upon just before the Confederate attack; or, if he had not then decided, General McClellan soon determined upon that plan.
To pass now to the Confederate side, where all was ready for the great movement.