Then disaster struck. The mule team nearest the far bank, unable to take the noise and the rushing water any more, bolted for dry land. Caught unawares by the sudden lurch their driver was hauled off his seat on the cart and swept downstream, the reins still around his wrists. The power of the current caused the reins to yank the terrified beasts to their right, toppling them and their wagon. The whole lot swept into the first line of legionaries, plucking eight from the rope as it crashed through them and on into the second line. The men on the second rope had time to see it coming. They dropped their packs and pila in order to hold on with both hands. The cart, the thrashing mules and their comrades cascaded into the legionaries, entangling them in a mesh of limbs, reins and wheel spokes. They held on for dear life and for a moment the whole avalanche slowed, straining the rope. The men to the front of the mess scrambled as fast as they could for the safety of the bank, whilst those behind shouted at their comrades to let go, but to no avail. With a sickening inevitability the weight on the rope wrenched the tree to which it was tied on the far bank from the ground, its roots already loosened by years of erosion. The rope with its cargo of men and debris arced out into the current towards the last of the pack-mules on the third rope. The unfortunate creatures were knocked off balance and away downstream taking those from the fourth rope with them, their handlers saving themselves by dropping their leads and clinging with both hands to the still secure ropes.
Vespasian watched as Corbulo and Gallus raced around trying to restore order to the crossing, but his attention was soon drawn away by the mounting noise of his men and their opponents. The Thracians were only two hundred paces away. With Corbulo busy down at the crossing it would now be down to him to issue the signals. He knew the theory from his lessons with Sabinus, all those months ago. He had seen them work in training on the march from Italia, but he had never seen them given for real. He knew that the timing was everything.
The archers to their front let off three quick long-range volleys bringing down nearly eighty of the tightly packed war band, but doing nothing to halt their advance.
‘Open ranks!’ he shouted at the cornicen. The low notes of the G-shaped instrument rumbled over the field, its deep tone audible to all over the din of battle cries. Immediately every other man of each century stepped behind his comrade to the right, creating passages for the now retreating archers to run through.
‘Close ranks!’ The cornicen sounded a different call and the manoeuvre was reversed.
Unencumbered by body armour the Thracians increased their speed steadily. They were a hundred paces out. Vespasian knew it would come soon.
‘Shields up!’ Again the cornu sounded. The rear three ranks raised their semi-cylindrical rectangular shields and stepped forward to hold them over the heads of the men in front of them. They created a patchwork roof that, if firmly supported, would keep those beneath safe from javelin, arrow or slingshot.
At forty paces from the Roman line the Thracians let out a huge roar and hurled their javelins. Hundreds of the iron-tipped missiles soared into the air and then arced down towards the three centuries and the cavalry to their flanks. With a thunderous clatter, like hail on an ox-hide drum, they rained down on to the waiting shields of the legionaries, thumping into the leather-covered two-inch-thick wood. The temporary roof held firm, with only the occasional scream indicating the inexperience of some rookie who had fatally let down his comrade to the front. The few gaps were immediately closed.
‘Shields down!’ Another blast from the cornu and the men lowered their shields, snapping off any javelins still embedded in them.
‘Pila ready!’ Shields and left legs went forward; right arms flew back with hands gripping the smooth wooden shafts of the lead-weighted pila.
On either side the cavalry commanders had both timed their charges to perfection. Giving the order on the release of the javelin volley they charged underneath it. They had smashed through and cut off the disordered flanks of the Thracians, who had not had the time to rearm themselves with their most fearsome weapon, the rhomphaia: a sleek three-foot-long iron blade, razor sharp and slightly curved back at the tip, attached to a two-foot, ash-wood handle.
With both flanks now isolated and fighting their own private cavalry-infantry battles, the main body came on, throwing down their shields; they would be of no use to them now for what they had in mind. Each man reached behind his head and with a sweeping movement unsheathed his rhomphaia, The Thracians broke into a reckless sprint wielding these terrifying weapons with both hands above their heads. Maddened by battle lust they screamed as they charged, bearded faces contorted with rage. Long cloaks billowed out behind them; heavy calf-length leather boots pounded down the grass.
Trying to remain calm Vespasian watched the approaching surge of hatred, counting to himself. This was the most crucial order and it had to be timed to perfection.
With twenty paces to impact he bellowed, ‘Release pila!’
The cornu sounded. The Thracians had travelled another five paces by the time the legionaries responded to the signal. As one, the three centuries hurled their heavy weapons at a low trajectory towards incoming wall of unprotected flesh. At the moment of release each man drew his gladius from the sheath on his right side and then put his weight on to his left leg and crouched behind his shield. Those in the rear ranks pressed their shields on to the backs of their comrades in front. They braced for impact.
Ten paces from the Roman line more than two hundred pila slammed into the howling stampede. Men were thrown backwards as if yanked from behind by an invisible rope. The barbed points of pila passed clean through their ribs, hearts and lungs, bursting out through their backs in sprays of hot crimson blood. Faces disintegrated as the lead balls at the base of the shafts punched holes through heads, exploding grey matter over the already blood-spattered bodies of those following behind.
But still they came on, leaping over their dead or wounded comrades, heedless of their own safety. Screaming their defiance at their iron-clad adversaries, they hurtled towards the rigid wall of shields, bringing the blades of their rhomphaiai hissing down through the air, trying to slice through the helmets of the men behind.
At the point of impact the Roman front rank pushed their shields forward and up. The bronze-reinforced rims took the impact of the rhomphaiai, snapping handles and notching blades with clouds of sparks. Iron shield bosses thumped into the chests of the warriors as they crashed into the solid Roman line, winding some and throwing others off balance.
The line held.
Then the short pointed swords, designed to stab and gut, thrust out from between the shields at groin height and commenced their lethal work. The bellows of rage turned into shrieks of pain and anguish as the iron blades pushed up through the vitals of the now stationary Thracian front line. Bellies split open, spilling their steaming contents over the feet of both attacker and defender alike. Genitals were severed, arteries opened and blood flowed freely.
The press of their rear ranks prevented the Thracians from using their rhomphaiai to full effect. They were used to more open combat, typical of their inter-tribal battles, where there was room to swing the weapon, lopping off the heads and arms of their opponents, or sweeping the legs from under them. Here they were of little account.
The battle turned into a scrum of pushing and stabbing. A couple of the inexperienced legionaries stabbed too far and felt an icy flash of pain. They quickly withdrew their arms to find only a blood-spurting stump, and went down screaming. The men behind trampled over them knowing that to leave a gap would be fatal for them all.