We must be winning, I remember thinking. We must be winning, because all these useless mouths are following us.

I related the whole scene to Thaïs, to pass the time, because she was in the eighth month and distinctly unhappy. I don’t think any woman, no matter how well beloved, loves her heaviest month, and for Thaïs, one of the world’s beauties, to have to face Barsines every morning over sherbet – Banugul on her way out to riding with the king . . .

Thaïs was only human.

But that morning, I remember that she heard me out and sent for Barsines. I had no inkling of what she was after, so I went about my work.

It became clear in an hour that we needed a new source of timber and a great deal more rock. Helios showed me the numbers, and begged me to get Diades an audience with the king. Or even with Hephaestion.

Diades was afraid it was over. Everyone was.

I took both of them with me, picked up Perdiccas and Craterus for support, and marched the lot of them to Alexander’s pavilions, where the hypaspitoi admitted us without delay.

Astibus caught up with me as we crossed the Aegema’s parade square. ‘He has the Persian slut with him,’ he said. ‘One of them. The Greek one.’ He shrugged.

In fact, I’d have sworn that Astibus was jealous.

I brushed him off and we went to the door of Alexander’s pavilion. Hephaestion was standing outside, which never happened. I made to speak to him, but he raised a hand brusquely, and then – lest I be offended – cupped his ear.

He was listening.

‘I am not interested in your protestations of love,’ Barsines said. The words floated out of the tent, and her magnificent voice was as hard as rock.

Alexander sounded plaintive – a tone of voice I had only ever heard him use with his mother. ‘I seek only to please you,’ he said.

She laughed. ‘Then take Tyre,’ she said.

Alexander was haughty. ‘I will choose to take it or not to take it as my strategy dictates.’

‘When a woman changes her mind on a whim, she does not pretend it is a strategy,’ Barsines shot back.

‘You go too far,’ Alexander spat.

Gods, he sounded just like a man. Not at all like a god.

Even the sentries were smiling.

‘You know nothing of war, nothing of strategy and nothing of how my mind works,’ he continued.

Barsines’ voice was a steel sword in a silk sheath. ‘My lord, I know none of these things. I only know that if my husband, Memnon, had set his mind to take this city, he would have taken it.’

Silence fell.

After a long, long hundred heartbeats, the most beautiful woman on the face of earth swept by me. She flashed me a small smile.

I turned my party around and marched them back out of the royal precinct.

‘Not a good time,’ I suggested to Helios and Diades, who were both deeply shaken.

But several hours later, as I went over Helios’s notes on wood consumption, Hephaestion poked his head into the command tent and grinned.

‘Back on,’ he said. He had the good grace to shake his head – he’d wanted to end the siege, but he was as much of a hero-mad fool as Alexander, and he did occasionally like to see the king taken down a peg.

And just like that, we were back to work.

We spent two weeks gathering new materials from new sources, and after the Athenian feast of Plunteria, we were back to work on the mole, and it went faster than before, because there was a broad base of gravel and rubble just below the surface to receive our work. It took us just two weeks to push the base of the mole out to where it had been before, and then we had a new enemy with which to contend. Because a stade short of the walls, the underwater ridge we’d used as the basis of our mole ran out, and we were now flinging rubble into deep water. It sank away out of sight, and after five days, we didn’t see any change.

Divers measured the distance to the bottom and said that it was over ten man-heights deep.

Diades rode away for three days while we stockpiled baskets and rubble and large stones, and he returned, gathered all the oxen and rode away again with a large force of Hetaeroi.

We worked. Alexander worked with us, and Hephaestion. Parmenio took ‘his’ half of the army and marched away south to clear more coastline. There was a rumour that Alexander had ordered him north, to reconquer Ionia, and Parmenio had refused the duty. Thaïs was days from delivery, and she wasn’t paying any attention at all.

Diades returned with four hundred great trees, all with their limbs and branches intact.

He had a plan, and it wasn’t what I expected at all. I sent him fifty men with bronze axes, and he sent them back. And then, in one long day and night, he threw all four hundred trees into the water at the end of the mole.

And we levered several thousand talents of gravel and rubble on top of them.

The Tyrians pounded us with their machines, because we were within a stade of the wall. But despite the work of their machines, we got the trees in the water. We’d pin each one we put in with rubble, and then put in another. We worked fast, and men died – men were pinned in the water by trees, or pinned to the mole by arrows. When it got dark, we worked by firelight.

The Tyrians landed parties on the beach behind us in tar-blacked boats and killed men going with empty baskets for more rubble. But I had ordered my phylarchs to come out each night in armour, and Craterus and Perdiccas did the same, and after the third night, the rest of the phalanx taxiarchs did the same, and the enemy raids slackened off.

The fourth night after the trees went into the water, I was leading a work crew on the edge of the mole itself. Every night, Diades begged us to work one more night without the protection of siege towers. His reasoning was excellent – as long as we could keep it up, we had men working on the whole forward edge of the mole – perhaps a stades wide, or the width of a hundred men lying on their backs, head to toe. As soon as we put up the towers and the wall, everything slowed down, and we had all seen how the mole narrowed because men didn’t like to work directly beneath the towers, which drew the most fire – so every few days, the width men worked got a little narrower. It was like tunnelling, in reverse.

The Tyrians came at us in boats – straight on. Thirty boats fired arrows into us – the thickest salvo of arrows yet, even in the dark, and my men fell. But another dozen boats full of marines rushed the head of the mole.

I had forty men in armour – all phylarchs, all veterans. I told the workmen to run as soon as I saw the boats come forward. Then the rest of us locked our shields.

It was ironic – in a deeply Olympian way – that we outnumbered the Tyrians about fifteen to one, but that there on the mole, they outnumbered us at least ten to one.

I remember it because it was bad fighting on bad footing, but also because I gave one of my best battlefield speeches. Remember, they weren’t all my men – we all took shifts, so I had men from every taxeis.

I said: ‘Remember that every man you kill here cannot face you from the top of their wall when the mole is done. Remember that we have thirty thousand Macedonians behind us, and we have only to hold these bastards for five minutes and we’ll have done a finer thing than any men have since the siege started. And remember,’ I shouted, as the boats grated against the mole, ‘that the only choice besides victory is death. I am betting victory is better!’

I received a heartening cheer. The worst feeling in the world is going into action with men who have no heart. These men cheered, and that gave the Tyrian marines pause. Then they started to form up.

‘Charge!’ I called to my own. Always better to be going forward, especially in the dark.

Our charge shattered them, even at odds of one to ten. About a third of them were out of their boats, and the arrows had stopped. What – did they think I’d just stand there and let them unload?