The three impressive battle lines were jumbled together now, but still they faced westward, as though their general believed his object was to reach the distant Potomac. In truth the enemy lay to the south, where Jackson had collected every man he could find and was leading them through the trees against the unprotected Yankee flank. Guns hid the noise of the advancing troops. There were rebel guns firing from the western hill and Northern guns firing from higher up the Hagerstown Pike, but then, drowning even the thunder of the artillery, an almighty crash of rifle fire splintered across the sky with a sound like the very veils of heaven being ripped apart.

The second division of Yankee reinforcements had climbed from the creek. They were supposed to follow the first division, which was now isolated in the West Woods, but the second division had lagged behind and now, reaching the plateau, they could see no sign of the men they were supposed to reinforce. For a few moments they waited, their general officers seeking directions amid the chaos, but then, lacking any orders, they marched southeast toward the beckoning landmark of a white spire of a Sharpsburg church that could just be glimpsed above the trees. For a few moments the Yankees advanced across the open farmland unobserved and unhindered, but in their path was a farm lane and the lane was an attacker’s nightmare. For years heavy farm wagons had broken the lane’s dirt surface and, because the track ran gently downhill toward open ground, the rains had washed the debris away so that year after year, generation by generation, the lane had sunk ever deeper beneath the farmland’s surface so that by now a man on foot could not see over the lane’s sloping banks. The Yankees did not know it, but they were placidly advancing over sunlit pastureland toward a natural firestep that was crammed with rebels. These Confederate troops guarded the center of Lee’s line and they had not fired a shot all morning, but now, at last, they pushed their rifle barrels through the long grass that grew beneath the rail fence at the bank’s lip and aimed at the unsuspecting Yankees. They let those Yankees come real close, then pulled their triggers.

Starbuck heard that first slaughtering volley fired from the sunken lane. The sound told him that the battle was widening as more Yankees crossed the creek, but his fight was still in the northern part of the field where five thousand Yankees were readying themselves to continue their westward attack, unaware that Jackson was coming from their unguarded southern flank.

Swynyard’s brigade advanced on the right, emerging from the trees where the woods narrowed to cross a small pasture. The Hagerstown Pike was immediately to Starbuck’s right, and beyond that lay the pastureland where the rebels had resisted attack after attack from the cornfield. The pasture was rilled with bodies heaped in rows like tidelines showing where the fight had ebbed and flowed. More bodies were folded over the fences, where men had been killed as they clambered over the rails to escape the Northern advance. Starbuck’s men walked past the horror in silence. They were weary and numbed, too tired to even look at the place where they had fought so long. A Yankee artillery battery stood well out of rifle range at the pasture’s far side. The battery’s guns were firing south, and every shot propelled a jet of flame-filled smoke that spat fifty yards from the gun’s muzzle before billowing into a vaporous mist that hung in the still air. The gunners appeared not to have noticed the rebel soldiers across the turnpike, or else they had more inviting targets to the south. Starbuck watched the gunners leap aside as their huge weapons leapt back with each shot. It was, he thought, as if those gunners were fighting a quite separate battle.