Brigonius found Tullio sitting in his own tent. Tullio had moved his household and his aides here for the building season; it was a place where he could watch over the progress of both the stone Wall to the east and the turf to the west. Some of his officers were here, including his close adviser the bucket-headed decurion Annius, and also his household slave. Karus and Xander were here, sitting with Lepidina, who looked bored. When Brigonius joined them they were winding down what sounded like a wide-ranging discussion of problems to do with the Wall, a conversation fuelled by wine served by the slave.

As usual Tullio was surrounded by heaps of paperwork. The army’s system of assignments was quite complicated, Brigonius had learned, with detachments being sent all over the province, and perhaps only half or two-thirds of the nominal strength of a given unit actually being in its home base at any time. But as a soldier of Rome, in your unit’s Acts your duties were recorded daily. It was the army’s meticulous record-keeping that enabled the commanders to know exactly not just where each soldier was supposed to be but where he actually was. And to maintain this vast mountain of recording whole teams of clerks were required, an army within the army.

But today the discussion concerned the Wall.

‘A fort every mile, two turrets every mile,’ Xander said firmly. ‘That’s the design. That’s what we are building.’

‘And I’m telling you,’ Tullio said, ‘that it can’t be done. You see, your design is all very well. I’m all for design. My cock would tumble out of my underpants without design. What I’m talking about now is fact, legionaries out there right now putting stones and turf blocks on the ground, one on top of the other. And if you try to follow your every-mile rule rigidly, Xander, you find yourself planting forts at the bottom of a gully where you can’t open the gates, or at the top of a crest where if you did open the gates you would fall out.’

‘Roman roads run straight,’ Karus said, himself faintly mocking. ‘Up hill and across valley; everybody knows that. Are you saying you can’t build a simple Wall to the same standard?’

Tullio ignored him. ‘And it’s not just the position of the forts. I’m hearing grumbles from the legionary tribunes who’ve been up on inspection from Eburacum. If an assault were to come, how are they supposed to deploy through those toy-town gates?’

Xander said stiffly, ‘I carefully computed the width and frequency of the gates to ensure—’

Annius said, ‘Yes, but the local farmers have to use them too. What are we going to say to the legate of the sixth when he finds himself queuing up behind a flock of sheep?’