Scipio looked sceptical. ‘To operate such machines would take valuable men away from the front line, men who could kill more of the enemy with their bare hands than with this contraption.’
‘They wouldn’t be legionaries. They’d be recruits of the third or fourth class, unsuited to front-line action. They’d be a specialised maniple of fire-throwers.’
Scipio pursed his lips. ‘You might use it against the wooden palisades of the Celts, but it wouldn’t be much use against a stone wall. You’d have to get close enough to project the fire over the ramparts, and then you’d be within easy range of the defenders’ arrows and javelins. As a battlefield weapon the burning naphtha falling on men would cause terrible injury, I’d grant you that, but assault under interlocked shields, the testudo, would provide a barrier, and by advancing rapidly the attacking force would soon be in relative safety, under the arc of fire.’ Scipio put his hands on his hips, thinking. ‘I can see its use in naval warfare, providing the wind was in the right direction and you didn’t burn your own ships. But for land warfare, I’d be on the centurion’s side with this one. It would be little more than a spectacle. Come on, let’s get back to the table before he arrives.’
‘Wait a moment,’ Ennius said, agitated. ‘We’ve only been thinking about a crude version, and I’d agree with you. That’s precisely why it didn’t go anywhere three hundred years ago. But my idea is different. Suppose you seal up one end of the tube, leaving only a small hole at the base to introduce the flame. And supposing you then pack the naphtha down the tube, and drop a stone or lead ball down on top of it, of a width to fit snugly in the tube and keep the gases from blowing out around it. The Greek scientists in Alexandria showed me that volatile substances can burn more violently when they are compressed into a small space. With this tube, it would not be the fire that was the weapon, but the missile. A heavy ball projected out of the tube at sufficient velocity could damage wooden walls, even stone ones. Smaller projectiles could be used on the battlefield: spheres of lead or iron, weighing less than a pound each. Thrown at high speed such a ball could decapitate a man, or tear him in half. As individual weapons, the fire tubes might not make much difference to the outcome of a battle. But massed together, fired in volleys like arrows or javelins, they could unleash hell. Even armoured men could be knocked down and killed by the shock of impact.’
Scipio stared at him. ‘Well, have you tried it?’
Ennius looked down, suddenly dejected. ‘The ball only goes part-way up the tube. The force of the naphtha isn’t powerful enough. I need a mixture that would really explode.’
Fabius cocked his ear. Over the months he had become attuned to the distinctive step of the centurion and the bang of his staff. And there it was. Thump thump bang. Thump thump bang. Soon there would be the clank of armour, the rattle of decorations on the breastplate. ‘Quick,’ he whispered to Scipio. ‘The centurion!’
Scipio clapped his hands and everyone hurried back to assemble around the table, all of them peering intently at the battle diorama. Ennius brushed the soot off himself as best he could and threw a cloth over the pots by the fireplace, then joined them. Scipio touched the small bronze gorget hanging from his neck that was the insignia of authority over the others given to him by the centurion, and straightened his sword. Fabius sniffed the air cautiously, and his heart sank. The smell of rotten eggs from the sulphur was unmistakable. The centurion was bound to notice it, and Ennius would be down doing duty with Hannibal the elephant for the next month.
He thought about Ennius’ concoction. Suddenly he remembered Julia, the ceremony she was attending today with her mother. The lictors who led the Vestal Virgins to the temple would throw clouds of coal dust into the air, and then thrust burning tapers into it. The dust would ignite, crackling and sparkling in a rainbow of colours. He glanced at Ennius, but then thought again. The last thing he wanted was for Ennius to blow up the Gladiator School. And Ennius needed to learn his place; there was a reason why the centurion came down harshly on him. Before he carried his experiments further, Ennius would need to earn his credentials in blood on the battlefield like the rest of them. Then, and only then, would men like the centurion listen to him. Fabius put the thought from his mind, and turned back to the door, tensing and coming to attention as he saw the figure who was standing there. Now the day’s training would really begin.
Marcus Cornelius Petraeus, primipilus of the first legion on three campaigns, was the most decorated soldier in the Roman army. Standing in the doorway, he looked as old and hard as an ancient olive tree, his legs and arms knotted masses of muscles and veins, his face creased and bronzed. In his left hand he carried a gilded bronze helmet capped with the crista transversa, the crest of the centurion made up of eagle feathers, and in his right hand he bore the other insignia of a centurion, the vine staff. Over his short-cropped white hair he wore the grass wreath of the corona obsidionalis, the highest Roman military decoration, awarded to him in Macedonia for killing his own tribune after the man had faltered, and for then taking over his maniple to lead it to victory. On his muscled breastplate were other decorations, the embellishments of more than forty years of war. Every time Fabius saw him at that doorway it was as if he were confronting an apparition from their hallowed past, as if the war god Mars himself had walked into the classroom. His battle credentials were second to none: the centurion had fought alongside Fabius’ own father and Scipio’s adoptive grandfather against Hannibal at Zama in North Africa, the very battle they had been war-gaming on the table in front of them.
They all knew that the centurion had intended to question them on the order of battle. From the corner of his eye Fabius could see the young arrival Gaius Paullus nervously mouthing the formation names to himself, knowing that Scipio had briefed him to answer the first questions. But then Petraeus curled his lip, sniffing. ‘What’s that reek?’ he growled. His voice was hoarse, and his accent was the rough country dialect of the Alban Hills. He smelled the air again, crinkling his nose. Ennius coughed, and looked down. Fabius closed his eyes, expecting the worst. The centurion grunted, sniffing loudly again. ‘Did someone break wind?’ His eyes alighted on Gulussa. ‘You haven’t been eating raw camel again, have you, Gulussa? I well remember your father Masinissa feeding it to us the evening before the battle of Zama. Later that night our tent stank like a sulphur mine. If someone had lit a fire, the tent would have ignited and risen into the air like a Greek firework.’ He guffawed, and waved his arm at the diorama. ‘That’s what you don’t learn here. The blood and guts of war. The smell of victory.’
Fabius let his breath out slowly. Ennius was off the hook, but they all knew that the new arrival Gaius Paullus was about to have his day of reckoning. He had been standing rigidly to attention, staring at the centurion. When Petraeus was like this, nostalgic about past battles, his hand clenching his staff, he was like a man stoking himself up for an evening in the taverns; only it was not the prospect of wine that was making his eyes gleam, but the prospect of blood. Today was the day of the month when criminals due for capital punishment were paraded into the arena, and the boys were allowed to use weapons on live victims. Today, Gaius Paullus would become a killer, if he had the stomach for it. Scipio knew the centurion would be as ruthless with Gaius Paullus as he had been with each of the others when he had first made them push cold iron into the chest of a living man.