But now the long hours were catching up to him. The fog increased his doubt.
"We're sure this grove is the root of our troubles?" he asked the centurion Longinus, who lay on the crest of the ridge next to him.
"So our spy said. We're never sure of anything in life, praefectus."
"I don't want to attack the wrong people."
"Right and wrong aren't easily sorted north of the Wall. The tribesman who befriends you one day will slit your throat the next, and the tribe that pledges allegiance in summer will attack in winter. It's all blood feud, cattle raid, and magic to them. If druids are there, though, they're Rome's enemies: enemies for all time. They hate and fear us because we rob them of power."
"I know all this. I just want to be certain."
"Certainty is for the dead." The centurion was impatient. None of the soldiers liked following a man who was indecisive. It created fear.
"I read they can foretell the future," Marcus remarked. "When he was just a soldier in the ranks, Diocletian once tried to shortchange a barmaid, and a druidess in the tavern chided him for being cheap. He joked that if he ever became emperor, he'd be more generous, and she scolded him for his jest and predicted he would become emperor-but only after he'd slain a boar."
"So he went on a hunt?" Longinus had never heard this story.
"He forgot the prediction. But before he assumed the purple, he had to kill the prefect of the Praetorian Guard. The man's name was Aper: the boar."
Longinus laughed. "Maybe she was just lucky. If your druids are really so prescient, we'd see them running from the trees!"
So Marcus rolled away from the edge of the ridge and stood straight, a glittering, vengeful angel. As always, early morning in Britannia was crisp, the May grass high and green, the trees exploding with leaves. Everything was wet and silvered with dew. The cavalry had left their lances crisscrossed in the grass because they'd be useless in the trees, and they created a Euclidian geometry on the hill. It seemed a day for poetry, not war. But if Marcus were to prevail in his ambitions, he must prove himself on the Wall, and to do so would require action like today's, delivering a message that was clear and unmistakable. Here he would avenge the insult to his bride. Here he would prove himself to Galba Brassidias. To his father. To his uncles. To his young wife.
Would Clodius do his part?
"Let the boy command one wing," Galba had privately advised. "He'll either win or be killed, and solve the problem either way."
It was the kind of brutal judgment the senior tribune seemed to make with ease. There seemed no philosophy to Galba, no hesitation, no remorse. No depth, no complexity. Yet the man exercised an influence over the soldiers that Marcus envied.
The praefectus waved, and they mounted, the horses snorting at this prospect of action, the rasping of drawn swords giving the praefectus a chill like fingernails drawn across a slate tablet. The automatic obedience to his orders still surprised him. No wonder Galba loved it! Longinus had suggested penetrating the grove on foot, given the difficulty cavalry had in dense forest, but Marcus was expecting a rout and a chase. Burdened by heavier armor, the army had long learned how useful the horse was in chasing down barbarians. The enemy, in turn, had learned the wisdom of skulking in forest or rock fields, where a cavalry charge couldn't overrun them. So be it: the druids would simply be either herded onto open ground, or trapped in their grove. Woods could be threaded. The Petriana trained weekly on negotiating thick ground.
"Signal to the other wing," he ordered. "Set the trap."
A pennant waved from the crest of their hill and got its answer from the opposite side of the vale. A signaler pressed his lips to the long lituus horn, using his free hand on the back of his head to push his lips against the metal with the necessary force, blowing with cheeks inflated. Its call echoed across the valley, low and warning, and birds flew up from the trees. Then they started down the hill, their rumble fracturing the morning's quiet. It was a slide of dun and silver, a jingling half-moon of men closing around the grove of oak, and as they thundered down the hill the sun broke from the horizon and lit the top of the mist with golden fire, like a promise of discovery. From within the forest another horn sounded, low and warning.
The Celts! The barbarians must be there as promised.
The Romans crashed through the edge of the wood and slowed, the trees dividing them like a sieve. Men lost sight of all but their closest comrades as they walked their mounts through the forest, pushing toward its center. Under the canopy it was still gray and foggy, the trees like ghosts. Mounts awkwardly skidded into gullies thick with the previous year's leaves and scrambled up muddy banks. As they penetrated, the cavalrymen began to lose any sense of direction, simply urging their horses forward in line with the sound of their comrades, wending this way and that on faint game trails-and indeed, their intention was to flush human game. They tensed and waited for a cry, an arrow, or the crack of branches signaling attack from above, but none came. The forest held its breath.
Marcus pulled up a moment to study the trees, his helmet heavy on his forehead. The oaks were huge, their limbs twisted as if in arthritic misery, their girth greater than the columns of Rome. They seemed so old as to be immune from time. There was power in this wood, and it fed barbarian boldness.
The trees themselves were his enemy.
From his right there was a shout and scream, cut short. A kill! He gripped his own sword tighter, but no challenge came. The wood ahead remained empty. He glanced to each side, his men cursing at the slapping branches and insulting each other as mounts stumbled. It was reassuring to hear the obscenities.
Suddenly a fugitive broke like a startled quail and darted away, a decurion whooping and galloping in pursuit. The quarry was agile, but the chase was short: a weaving horse, a stumbling Celt, and then the Roman running the barbarian into a tree, leaving his sword to pin the fugitive's torso so violently that its handle quivered from the impact. The man thrashed like a fish for a moment and then hung still. He was gray-haired and robed, Marcus saw. A druid? The decurion trotted back and dismounted to wrest free his weapon, and the body fell to the forest floor. Then the Roman wiped his blade and remounted.
They pressed on.
The cavalry reached a ditch, broad and old, its bottom black water. It curved left and right, appearing to make a huge circle around the center of the forest.
"Sacred water, praefectus," Longinus said. "Look, a dike."
On the far side of the ditch was an earthen berm that also formed a circle. If the Celts were going to resist, it would surely be here, at the boundary of their holiest trees. But no, there were no defenders. There was no one at all. The horsemen splashed through the still water and rode easily up and over the grassy earth of the inner ring. Their rank tightened.