infantry were conspicuously weak, for though plentiful, they had none of the drill of Alexander's Foot Companions. But Darius did not expect that the engagement would be won on foot.

Within this broad problem of encirclement, specific details were reported by scouts and needed close attention. In the centre of the Persian line, where by tradition a Persian king would take up his own position, Darius had stationed some fifteen Indian elephants whose trumpeting and tusking would scare off any frontal charge by Macedonian horses and riders who had never seen or smelt their like before. Some distance from the Persian front stakes and snags had been hammered into the ground as a further precaution against Alexander's cavalry, while closer to the line the plain had been levelled for a counter charge by the two hundred Persian scythed chariots. Their antique form of attack had been evaded by Greeks vith success before, but in the circumstances they posed an added danger. Their target was the phalanx as well as the cavalry, and to avoid them Alexander had best head for bumpy ground away from their level pitch. This bumpy ground, let alone a swing towards it, was likely to upset the massed sarissas of his own phalanx; like chariots diese were also most effective on smooth going.

There are few finer tributes to Alexander's intelligence than his plan to anticipate these dangers. The fundamentals of his battle line were those which he and his father had long exploited: the Foot-Companions, some 10,000 strong, held sarissas at the ready in the centre, while their unshielded right flank was protected by the 3,000 Shield Bearers, who in turn linked up with the aggressive right cavalry-wing of Companions, led by Alexander himself and preceded by some 2,000 archers, slingcrs and Agrianian javelin men for long-range skirmishing. On the left wing, the shielded flank of the Foot Companions joined directly with Parmenion and the Greek horse, who would fight their usual defensive battle as the anchor of the slanted line. The threat of outflanking and encirclement had called for special precautions. At the tip of each wing, Alexander had added mixed units of heavy cavalry and light infantry, concealing the foot soldiers among the horses and inclining the whole at an oblique angle to his already slanting front line, so that they extended backwards like flaps, behind his own forward cavalry and went some way towards guarding the flanks and rear if these forward units began to be encircled. If the encirclement continued, they were under orders to swing back to an even sharper incline, until they stood at right angles to the front line and joined, at their far end, with Alexander's second protection. This lay some distance behind the rear of the Foot Companions' rectangle and consisted of some 20,000 Greek and barbarian infantry arranged in a reserve formation, which would face about if the enemy cavalry escaped the flank guards and appeared at the gallop in the rear. This about-turn by reserves would change Alexander's army into a hollow oblong, bristling with spears to the front, rear and sides, and although there were obvious dangers if the rear units were forced back into their front-guards and robbed of any retreat, the use of reserves and a hollow formation were sophistications unusual, if not unprecedented, in Greek warfare. Designed for an outnumbered defence, it was to set an example which would not be forgotten ; specific plans against the elephants, snags and chariots would become clear in the course of the action.

After a sound but not excessive sleep Alexander gave the word for his units to take up these new positions and returned to don his armour in a manner worthy of any Homeric hero:

His shirt had been woven in Sicily, his breastplate was a double thickness of linen, taken as spoil at Issus. His iron helmet gleamed like pure silver, a work of Theophilus, while his neck-piece fitted him closely, likewise of iron, studded with precious stones. His sword was amazingly light and well-tempered, a present from a Cypriot king: he also sported a cloak, more elaborately worked than the rest of his armour. It had been dyed by Helicon, the famous weaver of Cyprus, and given to him by the city of Rhodes.

In this cosmoplitan dress he mounted one of his reserve horses and rode out to review his troops; only when the preliminaries were over would the ageing Bucephalas be led forwards.

Riding up and down the line Alexander exhorted each unit as he thought fit. To the Thessalian horsemen and the other Greeks on the far left under Parmenion's command, he had much to say, 'and when they urged him on, shouting to him to lead them against the barbarians, he shifted his lance from right hand to left and began to call on the gods, praying, so Callisthenes said, that if he were truly sprung from Zeus, they would defend and help to strengthen the Greeks'. This prayer says much for how Alexander wished himself to be seen. So far from being blasphemous or implausible, a reference to his own special descent from Zeus was the fitting climax to his harangue of Greek troops at a moment of high excitement; similarly, on the eve of battle, Julius Caesar would remind his men of his descent from the goddess Venus, whom he claimed as his family protector. Taken loosely, Alexander's words need mean no more than that Zeus was his ancestor, as for all Macedonian kings, and the same phrase could be applied, in this unexceptionable sense, to the kings of Greek Sicily or half-barbarian Cyprus. But this ancestry was undisputed, and neither Alexander nor his court historian would ever have hedged it about

with the words 'if it were truly so ..This cautious reference implies a deeper meaning, and to an audience who had lived with the rumours and flattery that had gathered since Siwah, the words would surely have been taken as hinting at direct sonship of the god. Even then they were an encouragement, not an impossibility; their guarded phrasing is not a proof that Alexander was sceptical of stories of his own divine origin. Unlike others, he realized that such delicate matters can never be considered certain. Support was given by Aristander, his tame prophet, who accompanied him along the lines, dressed in a white cloak with a crown of gold on his head: he 'pointed out an eagle', symbol of Zeus and of Alexander's own royal coinage, 'which soared above Alexander's head and directed its flight straight against the enemy'. Preparing to fight for their lives, no troops would wish to dispute that the bird in the sky was anything less momentous.

Orders and exhortations take time to be delivered, and it cannot have been long before midday that Alexander finally marched his 47,000 men down into the plain against a foe some six times their numbers, whom they had kept waiting under arms, fretful and sleepless, for the past two days. Much ingenuity has been devoted to what follows, but there were facts in the advance which only serve to discredit such attempts; no general, least of all a rival of Achilles, had remained on a vantage point to describe the overall engagement, and no historian, least of all Callisthenes, was in a position to survey the scene with the naked eye. Such a broad view would clearly be impossible: the enemy were relying on horsemen, who always charge and career in frantic competition, and the plain beneath Tell Gomel is dry and dusty. Every account agreed that the battle would end in a billowing dust-cloud. When orders could only be passed by trumpet or word of mouth to distant commanders whose line-up left them to choose between several alternative positions, this dust is a disruptive fact of the first importance: 'Anyone who has witnesscd a cavalry charge in dry weather over an Indian maidan will be able to picture what the dust at Gaugamela was like. On one such occasion, the writer remembers that visibility was reduced to four or five yards.'* In every account of the battle, ancient and modem, the dust is only allowed to intervene when the fighting is almost finished. But if the retreat was obscured by a dust-cloud, so too was the advance over exactly similar ground; like philosophers, historians of Gaugamela would do better first to raise the dust and then complain that they, like Alexander, are unable to see from the start.