The fighting raged furiously at this critical point and for a considerable time its result was in doubt, with the chances strongly in favor of the Federals. Three times the tide of battle ebbed and flowed across the disputed field, both sides fighting with a courage and obstinacy that were scarcely to have been expected of troops so little inured to the work of war.

When the struggle was at its fiercest, and at the moment when the promise of it seemed to be that the Federals would overwhelm and crush their sorely outnumbered adversaries, a strong detachment of Johnston's troops from the Valley, long delayed on their railroad journey, reached the field. Their orders were of the vaguest, but they plainly saw an overmastering Federal force pressing the Confederates very hard in their immediate presence. So, following the Napoleonic instruction to go to the point of heaviest firing the officers commanding the arriving Confederates went at once into the thick of the fight.

It was the work of a brief time for these fresh men to envelop the advancing Federal right wing and crush it to pulp.

In the meanwhile the sorely beset left wing of the Confederates had been enabled to hold its ground and save itself for a time from complete disaster, only by the obstinate courage of a brigade of Virginians under General Thomas Jonathan Jackson—a West Pointer who had long ago resigned from the old army to become a professor in the Virginia Military Institute, and who had now become a brigadier-general of Virginia volunteers. He had already so completely won the hearts and dominated the minds of his men that—raw volunteers as they were—they had no thought of faltering or flinching in the presence of any danger, so long as their chieftain bade them stand fast. One after another the battalions with which they had touched elbows were beaten back before a leaden hailstorm, or torn to shreds by cannon fire at murderously short range, or fairly forced to the rear by bayonet-armed phalanxes, while their own brigade line was steadily withering under the destructive fire. But they were under inspiration of a leader whom they loved and whose courage was inspired by a religious faith as unfaltering as that of any Mussulman fanatic, and so they stood steadfast in spite of all. They looked for their orders only to that great, calm, passionless leader, and from him alone they took their impulse. Scarcely at any time during a war that abounded in illustrations of heroism, was there, on either side, a more conspicuous example of the courage that endures, than that which was afforded by Jackson and his Virginians at that most critical moment of the first great battle. It excited admiration and inspired others with courage even in that hour of seemingly hopeless defeat. General Bee, who was destined a few minutes later to become a martyr to his own courage, seeing it, cried out to his wavering men: "There stands Jackson like a stone wall," and appealed to them to emulate the example of their comrades and "rally on the Virginians." From that hour to this the title "Stonewall" has clung to the fame and memory of Jackson more closely than his own proper name has done.

Under the fierce onset of Johnston's fresh men, supported by rallying brigades that had for a time faltered and yielded ground, and reinforced from the Confederate right, the Federal assailing column was quickly crushed and forced to retire, the Confederates pressing hotly upon their heels.

Then occurred that insane panic in the Federal army which has never been explained or accounted for except upon the insufficient ground that its victims were men without discipline and wholly unused to war. The explanation leaves much to be desired. The men who yielded to that panic impulse had already on that day proved themselves brave fellows, quite capable of doing soldiers' work right gallantly. They had fought with vigor, determination and high courage through long and bloody hours. They had been the assailants where assault required a greater courage than defense and they had done their soldierly work altogether well. They had been baffled of victory in the crowning hour of the battle, but they perfectly knew that their columns still outnumbered those of their adversary, and they must have known that in an orderly withdrawal from the scene of the conflict they were not in the least degree likely to be destructively assailed in their turn. Nothing was more unlikely indeed, than that the Confederates, having exhausted their freshness of vigor in the battle and having achieved their immediate purpose by repelling their enemy's assault, would in their turn advance upon that enemy, still outnumbering them, if he had withdrawn in good order and taken up a strong defensive position at Centreville, only a few miles away. Had the Federal Army done that, preserving its cohesion and presenting a determined front, it is indeed certain that the Confederates would not have cared to convert their successful defense into a more than doubtful offense; and even had that happened through Confederate over-confidence, the opportunity of the Federals to convert their own defeat into a conspicuous victory would have been as tempting as any that an army could desire.

Later in the war after the two armies had been molded into effectiveness by the stern discipline of service, some such course as this would undoubtedly have been pursued. But at Manassas the event was startlingly different. No sooner did the Federal troops that had fought so gallantly on the right of their line find their assault repelled and themselves forced back than all cohesion, all discipline, all soldierly qualities went out of them. They broke ranks and fled in a positively demented panic, which unfortunately proved to be instantly and universally contagious. The whole army fell into confusion. Even those parts of it which had successfully held their own in severe conflicts throughout the battle hours broke ranks and ran as an unorganized mob might at the advance of a force of regulars armed with bayonets.

The Confederates, flushed with unexpected victory achieved in the moment of defeat, pursued them with all the quick-moving forces available, chief among these being Stuart's small body of Virginia cavalry.

There was a report current in the Federal army that J. E. B. Stuart had under his command thirty thousand of the finest and most desperately daring horsemen that had been known in the world since the days of the Mamelukes. As a matter of fact, he had under his orders five or six hundred young Virginians. They knew how to ride their horses, they knew how to use their revolvers, and they knew in some degree at least how to handle their sabers. They had been trained to all that all their lives and perfected in it at the camp of instruction at Ashland. But beyond that they had no skill and no superiority and it was their constant wonder after the battle of Manassas, that during the chase they almost nowhere met the cavalry of the other side. They met and quickly dispersed artillery and infantry, but nowhere did they encounter men of their own arm of the service. They had met and fought horsemen in the Valley of Virginia—for Stuart had been with Johnston there—but they encountered none such now.

The simple fact is that the Union army was in an insane panic and utterly disorganized. The sole thought of every man in it was to escape with a whole skin if that should be in any way possible. The cavalry men having horses under them put spurs to their steeds and led instead of protectingly following a confused and confusing retreat upon Washington. Artillery men cut their horses out of their gun carriages and caissons, mounted them, and fled bareback at such speed as the horses could make.