‘Really?’ Cato muttered. ‘We’ll find out soon enough. Come on.’

He turned and led his optio towards the exit from the camp. As he reached the edge of the small clearing Cato turned to call out to the others over his shoulder.

‘No one leaves the camp. Stay alert.’

Cato strode down the track into the swamp, mentally mapping the tracks he had used since they had found the camp. If Metellus was making for the farm then he would most likely take the track they had followed the day they killed the pig. It had been one of the few patrols Metellus had been out on. Cato had worried that the man’s disrespectful attitude might have caused problems, and had confined him to the camp as often as possible. There was a quicker way to the farm, a narrow track that almost disappeared into the marsh in places. It was hard to follow, but if Cato and Figulus hurried they might yet reach the farm before Metellus, and stop him from doing anything foolish.

So he hurried on, sacrificing the usual wary caution with which he had moved through this dismal landscape to the need for speed. The sun shone from a clear sky overhead and the swirling clouds of insects that hovered amongst the reeds closed round the sweating Romans as they waded through small stretches of the thick foul-smelling mud between lengths of the track that snaked through the marsh.

‘What do they eat when Roman’s off the menu?’ Figulus muttered as he angrily swatted a horsefly that was gorging itself on his neck.

Cato glanced back. ‘If we don’t stop Metellus in time, then there’ll be a lot more Romans on the menu. Come on!’

They had been going for nearly two hours, when Cato realised that the landscape around him was wholly unfamiliar. From the position of the sun, he knew they must be headed in roughly the right direction, but they should have come across the farm long before now. They must have missed it, passed it by, and failed to find Metellus. It was with a sinking heart that Cato was helping his optio out of a deep patch of mud when he glanced back the way they had come and froze.

‘What is it, sir?’

Cato just stared for a moment longer and then pointed. ‘Look there . . .’

Figulus stepped up on to the earth bank and straightened, following the direction indicated by his centurion. At first he didn’t see anything unusual, then a faint smudge blossomed in the distance.

‘I see it.’

As they watched the smoke thickened into a thin grey column that trailed up into the clear sky. The base of the column pointed unerringly to its source.

Cato glanced round at the sun, still well above the horizon. ‘There’s still an hour or two of light left. Too much. We have to get back, quick as we can.’