‘Neither did I.’ Macro grabbed his arm. ‘Come on. Let’s go.’ Macro led the way as they ran back to the depot. As soon as they were through the gate he sent one of the sentries to summon the tribune and Tincommius. As the man ran off down the lane towards the royal enclosure Macro turned to his subordinate.

‘Get the Wolves formed up by the gate. I’ll rouse the Boars and join you as soon as I can.’

‘Yes, sir.’

Cato sprinted towards the headquarters building and burst through the door into the admin hall. Catching sight of one of the garrison’s trumpeters, he shouted at the man to get his instrument and follow him to the main gate of Calleva. The man arrived on the walkway breathless from running under the weight of the curved brass horn, and having to climb the ladders to join his commander. Cato slapped his thigh impatiently as he waited for the man to catch his breath. At last he spat to clear his mouth, drew in a deep breath and blew into his mouthpiece. The strident notes of the assembly call rang out over the town and the men of the Wolf Cohort hurried towards the sound.

Over in the depot another signal rang out and, glancing round, Cato saw the men of the Boar Cohort tumbling out of their tents to assemble on the parade ground. The squat figure of Macro emerged from the headquarters building, helmet glinting in the first rays of the sun beneath the red flare of his transverse crest. He was fully armoured and ready for action. With a pang of self-contempt Cato realised that he had left his armour in his quarters, and he turned to the nearest man and sent him to fetch it.

Beneath the walkway the gates groaned as they were swung inwards. The first men appeared in the muddy street below and Cato leaned over the parapet to shout his orders down to Figulus.

‘Form the cohort up on the road inside the gate!’

As the Roman instructors bustled the men into position and began to form the cohort into a marching column Cato looked over the wall towards the distant spires of smoke rising into the sky, perhaps four or five miles away. The air was quite still this morning and it was possible to distinguish several separate sources of the smoke: the individual supply wagons fired by the attackers, Cato reasoned. As the last men hurried into line the native he had sent to fetch his equipment arrived on the walkway, panting from his exertions. Cato frowned when he saw that the man had not brought him a fresh tunic, but there was no helping that now, and he pulled the shoulder padding over his head and reached for the heavy mass of his chain mail.

‘Will there be a fight, Centurion?’ the man asked as he fastened the buckle of Cato’s sword belt.