The Atrebatan warrior selected a youth, scarcely more than a boy, whom Cato recognised as one of the mule herders from the depot. The boy shrank back, shaking his head, but his captor grabbed him roughly by the hair as he slipped the knot that bound the boy to the rest of the prisoners. With a savage wrench the warrior hauled the boy out of the column and dragged him, writhing and screaming for mercy, towards the prone form of the first victim. Macro stood still, but Cato could watch no more, and turned away. He hurried to the ladder and swung himself down into the enclosure. As he reached the ground he heard the sickening crunch of a blow being landed and the boy’s scream cut through the morning air like a knife thrust deep into Cato’s guts.

All morning it went on, and the broken bodies stretched across the street. There was no pause in the screams and cries of the Romans now that so many of them had been crippled and left to suffer the agony of their shattered limbs. Macro made himself stay on the gate, silent and unyielding in the face of Tincommius’ regular demands for surrender. And each time, when Macro refused to reply, the next captive was dragged forward, in full view of the defenders on the gate, and beaten savagely on the legs until they broke. To add emphasis to the process Tincommius ordered the warrior with the club to begin breaking arms as well and once he had broken both shins he began on their elbow joints.

For Cato, even well away from the gateway, there was no respite from the horror, as the screaming continued unabated. No one in the royal enclosure spoke. Most sat staring at the ground, visibly shaken every time a new victim added his cries to the shrill, nerve-shredding chorus. Some men spent the time sharpening their swords with vigorous rasping strokes of their whetstones that did little to drown out the hellish din from over the wall. Finally, Cato could stand it no more and climbed up to join Macro. The older officer had not moved, and stared down the street with a fixed, implacable expression. He spared himself only the briefest of glances at Cato.

‘What is it?’

‘I’m worried about how much more of this the men can take . . . sir.’ Cato nodded discreetly towards the men in the enclosure. ‘It’s wearing ‘em down.’

‘Wearing you down, you mean,’ Macro sneered. ‘If you can’t stomach this, then what are you doing in that uniform?’

‘Sir!’ Cato protested, shocked by Macro’s vehemence. ‘I . . . I . . .’

‘You what? Go on, say it.’