The soldiers carrying the bucinas heard the command and did not wait for it to be relayed to them. They pursed their lips and raised their mouthpieces and blew. Three strident notes blasted out across the battlefield. The signal was repeated and before the last note died away the two columns of legionaries began to advance, fighting their way forward along the sides of the Nubian horde, out beyond the buckling line of the Roman units holding the centre. Beyond them the cavalry cohorts also advanced, in echelon as they covered the flanks of the Roman army.

At first the Nubians appeared to be unconcerned by the columns of legionaries extending around the edge of the host. Those in the centre were still convinced that victory was in their grasp; they fought like lions to break through the Roman line once again. Cato saw a silken banner rippling from side to side above the centre of the Nubian ranks and he realised that Prince Talmis had come forward in person to urge his troops to shatter the slender force that still held them back.

The flanking cohorts tramped forward until the last century had linked up with the main battle line. Then they stopped. A command was passed down the line and each cohort turned inward to face the sides of the massed warriors of the Nubian army. Another command echoed along each of the extended wings and the legionaries formed their shields into an unbroken wall. Then they advanced, pressing the enemy back before them and cutting down all those who came within reach of their short swords.

While the legionaries closed the trap, the auxiliary cavalry charged forward, cheering as loudly as they could as they made for the enemy horsemen still formed up some distance behind their infantry. If the enemy’s nerve held, no amount of noise and raw courage would save the outnumbered auxiliaries from eventual defeat. Cato had calculated that their sacrifice would buy enough time for the rest of the Nubian army to be defeated. However, as he watched, the Nubian horsemen and the camel riders began to break away from their formations, individually at first, then in small groups, streaming away across the landscape to the south.

‘Bloody hell,’ Junius exclaimed bitterly. ‘What do they think they’re doing? The cowardly dogs!’

Cato nodded. Only a handful of the Nubians stood their ground and were quickly cut down by the mounted auxiliaries. The suddenness of their victory went to the heads of some of the Roman horsemen and they set off in pursuit before their officers could stop them. However, most began to trot back to form up on their standards, and they turned to form a line across the rear of the mass of Nubian infantry still attempting to overwhelm the centre of the Roman line.