A cry came from somewhere near the gate, picked up and echoed all along the wall. The defenders threw up their arms, raising spears and javelins, and let out a great shout.
‘Maximianus Augustus! Eternal Emperor!’
Three times they cried, then every man battered his shield rim and the noise reverberated across the valley towards the advancing enemy.
Leaning from the door of the tower, Castus stared at the columns as they approached the wall. His throat was tight, and his breath came in short stabs. Sweat was rolling down his back. He realised that he was digging his fingertips into the stone of the wall beside him. For the first time he allowed himself to wonder what he would do if the attackers reached the ramparts. He would fight – he would have to, or die in the melee. But those advancing men were his brothers, his comrades. He could see their shields now: I Flavia Gallicana in the lead. Some of those men would have fought at his side in the riverbank battle against the Bructeri. Behind them came XXII Primigenia and I Minervia. All legions he knew, men he knew.
And yet, when he glanced along the wall he was willing the archers to watch their aim, look for their marks, make every arrow count. Without even thinking, he had drawn his sword. The logic of battle was carrying him now, and his blood was hot and quick with anticipation.
The advancing columns had passed the brick heaps that marked effective archery range. Down on the rampart, a centurion of the Seventh raised his stick, then let it fall. At once bows bent all along the wall, and the slingers began to whirl their slings higher. A heartbeat, held in tension, and the first volley was released.
Arrows and shot flickered from the rampart; some fell short, but most struck the advancing shield-blocks with a loud percussive thud and rattle. The assault columns let out a great roar, amplified under the roofs of shields, and broke into a charge, trying to close the gap to the walls. Another volley of arrows – now each charging testudo bristled with black shafts. Castus was holding his breath, wide-eyed.
An arrow flicked past his face and hit the tower wall, striking sparks off the stone. Down on the rampart below him two men dropped to the walkway, struck down by slingshot. Moving up behind the assault columns, the opposing archers and slingers had begun to return the missile barrage. Edging up from his crouch, Castus heard the strum of bows from the tower chamber behind him. Then a scream, echoing from the doorway; he glanced back and saw one of the Mauretanian archers fall sprawling with an arrow in his neck. Blood pulsed from the wound, and his heels battered the flagstone floor.
Outside, the sudden charge of the assault columns had carried them across the open ground and almost up to the fortifications. Now they had to negotiate the low rubble wall and the deep ditch. Castus saw the front rank of the leading column falter as one of their men was hit and went down in the dust. The shields broke apart, men stumbling out of formation and cascading down the outer slope of the ditch. At once arrows were flicking between them as hundreds of archers on the rampart aimed down into the shattered testudo. Another man fell, then half a dozen in a heartbeat. The rest spilled forward, hefting their ladders overhead as they swarmed down into the gulley of the ditch and piled up towards the wall, yelling.
A party of archers had climbed to the tower rampart and were shooting down directly into the mass of the attackers. Castus leaned from the doorway again and looked up, just as one of them was struck by a slingshot and toppled forward over the wall. The body fell, a brief dark blur trailing red.
‘Aim for the enemy archers and slingers!’ Castus yelled into the chamber behind him. ‘The ladder-men are below the wall, you can’t hit them – aim for the archers and slingers!’ He saw Glyco staring back at him, a smudge of blood across his forehead.
The assault columns had broken formation now, the attackers clambering up out of the ditch in groups of three or four, holding their shields above their heads. Several of those down at the Rome Gate had pickaxes and crowbars, while others carried burning fire-pots to try and burn the gates. Javelins darted at them from the ramparts.
Already the first of the ladders was rising towards the wall close to where Castus was standing, a knot of men below sheltering their comrades with their shields as they wrestled the wooden lattice up into position. Two more ladders swayed up only a score of paces away. Hardly had they touched the stones when the first of the attackers was scrambling up the rungs with his shield above his head. Up on the rampart walk, the defenders were dragging one of the heavy baskets of stones and rubble and lifting it to the parapet.
Castus stared in grim fascination as the basket was manoeuvred across the ledge of the wall and began to tip. The men below were climbing fast, but not fast enough. A rush and a crash, and the weight of rubble cascaded down, knocking them screaming from the toppling ladder in a torrent of dust.
Another ladder cracked into position against the wall, and immediately it was creaking under the weight of armoured men. The defenders on the walkway bunched and crouched; this time they were lifting a single great stone between them. It looked to Castus like a column drum. Pulling his helmet laces tighter, he leaned out over the parapet, gazing down at the men hauling themselves with savage determination up the ladder. Above them the great stone was in position, the defenders shunting it across the ledge of the wall until it tilted and fell.
The plunging stone struck the leading man, crushing his skull and bursting his torso, then crashed straight down through the rungs of the ladder, shattering it. Broken bodies fell into the wreckage, clogging the ditch below.
Arrows jarred off the rampart parapet, and Castus pulled his head back quickly. The archers below the wall had learned to concentrate their shots towards the tops of the ladders, driving the defenders back and giving the climbers time to scale higher. All along the rampart walk there were bodies sprawled, writhing, limbs struck with arrows, heads broken by slingshot. There were six ladders against the wall now, and the climbers were pushing higher.
‘Out the way,’ somebody said, and a man shoved through the tower doorway. After him came the second Praetorian, Glyco.
‘You just planning to watch, dominus?’ Glyco said, glancing back at Castus with a disgusted sneer. Then he jogged down the steps to the walkway after Ursus. Castus drew a deep breath, wanting to shout after them. But what could he say? His perceptions seemed to have slowed, and everything around him shone with a bright glaze. The air was fogged with dust, whirling in the sunlight.
Something was happening on the wall, a strange pause that for a moment Castus could not understand. He leaned out again, and his breath caught.
The leading climbers had reached the tops of the ladders, but they were still a good six feet below the parapet. The ladders were too short. Castus stared, incredulous. Could they really have miscalculated the height of the walls so badly? The men at the top of each ladder were trapped by those coming up behind them, and already the defenders on the ramparts had regained the offensive, stretching out over the walls to fling stones and javelins directly down into their faces. Bodies began falling. One of the ladders tipped sideways, men cascading off it with wild screams.
Still the climbers pushed upwards. The men at the top were struggling onto the shoulders of their comrades below and stretching their hands up to try and grab at the stone parapet. Castus could see their faces, straining and sweat-drenched. He could hear them crying out, their voices maddened, cracking. Another ladder toppled, leaving a single man still dangling on the parapet until the defenders above speared him and he fell.