He knew. He had known all along. Both men were now glaring at me, the impostor.

So Fulvius had had told Diogenes his nephew worked as an informer. It could even be my fault that getting these scrolls removed from the Library then packed up and shipped tonight had become so urgent: my father could well have reported that Helena had a.s.sured him I was close to uncovering the scams at the Museion. told Diogenes his nephew worked as an informer. It could even be my fault that getting these scrolls removed from the Library then packed up and shipped tonight had become so urgent: my father could well have reported that Helena had a.s.sured him I was close to uncovering the scams at the Museion.

Now I was in trouble. The box-maker had grasped the situation. He stood up. In his right hand appeared a small knife that he must use for box-making; its narrow, shiny blade looked hideously sharp. 'What did you bring him here for?' he demanded accusingly 'To get him away and deal with him,' Diogenes replied.

The workshop and its rectangular doorway were about six feet wide; with the shutter half pulled, Diogenes filled most of the doorway, blocking escape that way. He had no weapons on show, but looked tough enough not to need one. He yanked the shutter further towards him. I was now trapped indoors with them, and any cries for help would be well m.u.f.fled.

This was no time to hesitate. I half turned, hoping for the possible one chance - yes, at the back of the workshop, uneven wooden stairs ran up. I bounded up them fast, fully aware this could put me in a worse trap. I came through a hatch into the dark living-room-c.u.m-bedroom such places often have, where the workman can live cheaply with his family. I grabbed the bed. One built into the wall would have failed me, but this one was free-standing. I shoved it hard clown the hatchway, jamming the legs as best I could so it blocked the stairs. There was another way up, little more than a vertical ladder. It brought me one floor higher, in among old boxes and box-making materials. At first I thought I was stuck. But we were in Alexandria; the place had access to the roof. The door was barred, but I managed to free it. I pushed my way out into fresh air, under the night sky.

I could hear Diogenes and the box-maker coming up hard behind me. Nothing for it but to shin over a parapet wall on to the next roof. I ran straight across and clambered through some kind of reed screen. I kept going. From then on, the buildings were separate, but along the street they were so close together I could take a breath and leap. So I continued from one house to another - not always easy. People had gardens up there; I fell into giant flowerpots. They stored furniture; I hurt my legs on chairs and beds. I startled moths. A stork flew up and frightened me. At the far end were select apartments where family occupiers led leisured evening lives. At one, enormous women sat out on long, battered cushions, drinking from small copper cups and chattering. When I flew down among them like an ungainly owlet trying out his wings, the shocked ladies squealed, exuding sour breath and raucous laughter. But they heard my pursuers coming and at once blew out several oil lamps so they could hide me quickly among their husky-scented soft furnishings. I lay there trying not to choke. Diogenes and his companion thumped on to the roof and were sent on their way with extravagant curses.

Emerging, I faced a tricky moment with a crowd of excited women who appeared to think the G.o.ds had sent me as a mercurial gigolo. But amidst many giggles and painful pinches, they sent me down a narrow stair, which let me out at street level. It must be the way they admitted their lovers, I thought (admiring the stamina of men who could deal with such heavies). But they were women with good hearts, quick to grasp an emergency. I had thanked them genuinely.

I emerged in a dark alley. It smelt the way they all do, with some extra strong Egyptian whiffs. I had no idea where I was. I recognised nothing. I saw n.o.body from whom I could ask directions, even if I dared trust them. My pursuers could at any moment burst from some other doorway.

Suddenly, a cat meowed. I started. 'Get lost, filthy moggie. I'm a Roman; you're not sacred to me.' I flattened back against a wall, breathing hard.

While I listened for trouble, I thought grimly about Vespasian and my supposed 'mission' as his agent. In fact I had no mission, not in the paid sense. My reasons for visiting Egypt were exactly as I had told everyone: Helena wanted to see the Colossus of Rhodes, and the Pyramids and Sphinx; because of her pregnancy we had had to travel as soon as possible. Uncle Fulvius had made us a convenient offer to stay with him. The Emperor meanwhile was completing his new overspill Forum, called the Forum of Peace; in it would stand a new Temple of Peace, while dominating the temple forecourt would be two beautiful public libraries, one Greek, one Latin. All Vespasian had said to me was: 'If you are in Alexandria, Falco, take a look at how the Great Library works.' There was no mention of scrolls. I reckoned he had not thought ahead as far as making acquisitions for his new buildings; it was, of course, a good moment for an entrepreneur to turn up in Rome offering cheap books.

No way would the Emperor pay pay me to come and look at the Great Library. The mean old beggar was making no contribution to my travel expenses and the only reason I would actually complete a report for him would be a vague hope of future grat.i.tude. Helena believed that in return for a good brief (which she had promised to write), the Emperor would give me a big thank-you. I thought he would just laugh. He had a reputation as a joker. Trying to screw payments out of Vespasian was the biggest joke on the Palatine. me to come and look at the Great Library. The mean old beggar was making no contribution to my travel expenses and the only reason I would actually complete a report for him would be a vague hope of future grat.i.tude. Helena believed that in return for a good brief (which she had promised to write), the Emperor would give me a big thank-you. I thought he would just laugh. He had a reputation as a joker. Trying to screw payments out of Vespasian was the biggest joke on the Palatine.

So for this nebulous concept - a job that had never existed - I was now being hunted down by the hostile confederate of my scheming relatives. They knew nothing about the trouble they had landed me in; they were ensconced at home with their feet up, while doting women tended them with dollops of hot broth.

I now saw what their scheme was: acquiring scrolls cut-price from the twisting Museion Director, shipping them across the sea then presenting them in Rome as an easy-buy, save your on-costs, complete package for the so-far empty libraries of the Temple of Peace. If I knew Pa and Fulvius, they would recoup seven times their investment. The grim-faced Diogenes would want a large cut - but that shifty pair would still make an enormous profit. Was any of it illegal? It was certainly illegal in intention, intention, for everyone from Philetus and Diogenes to Fulvius and Pa. for everyone from Philetus and Diogenes to Fulvius and Pa.

I was implicated as a relative. Since I was staying in the same house, it looked doubly bad. I doubted that even the eminent Minas of Karystos could get me off charges of guilt by a.s.sociation.

Furious, I walked to the end of the alley and I surveyed the street in both directions. I was hoping for a donkey that I could 'borrow' - better still, if I saw a man with a horse and cart, I would offer him a large sum to take me back to the centre; I could name somewhere he would be bound to know, the Caesarium, for instance, or the Soma, Alexander's Tomb...

But my surveillance remained unfinished. I wanted to discover what ship Diogenes was using. It could already be half laden. I also needed to stop him conniving further with Fulvius and Pa - and stop him telling them that I was on to their project. I would like to arrest Philetus and Diogenes, but saw no way to do that without involving my relations.

Walking about, at last I recognised the street where the box-maker lived. All members of the public had now dispersed; both the baths and the temple looked closed for the night. As I turned up, a second horse and cart was arriving with the two clowns I saw at the Library, bringing a whole load more of scrolls. Despondently I parked myself in the shadows. A donkey came trotting by, carrying two men who from their build and manners looked like brothers, similarly dressed in black desert robes, with head-dresses they had wound up to cover their faces as if a sandstorm threatened. They stopped and looked at the box-maker's, but rode on. n.o.body else was about now, not at street level. I could hear woozy music from behind closed shutters, and voices from inside houses or shops. People had hung up lights, though at infrequent intervals.

As I continued to watch, the two clowns loaded up the first cart with filled boxes. Once all the boxes were in place, Diogenes came out and a.s.sumed the driving seat. As the clowns began unloading loose scrolls from the second cart and carrying them indoors to be packed by the box-maker, Diogenes set off.

The horse was tired and went quite slowly. I followed on foot. At one point, cursing, I had to stop to pick a sharp stone out of my boot. As I leaned one-handed against an awning support, fiddling madly, a donkey pa.s.sed me, with two riders. It was the one I saw earlier. A while later, when the same donkey was drinking from a horse-trough, I overtook them again. The two men did not look at me; I wondered if they knew I was there. Somehow, I hoped not. I was starting to ask myself whether, just as I was tailing Diogenes, the two donkey-riders might be following both of us.

Diogenes went on in one direction, apparently aiming for the Western Harbour. He had turned north towards the ocean. Somewhere ahead must be the ca.n.a.l which I knew came through to this harbour from Lake Mareotis. To our right at the far end of its causeway stood the dark shape of the Lighthouse, topped at this time of night by the mighty glow of its signal fire, reflected out to sea but eerily lighting up the topmost turret. Diogenes turned on to Canopus Street, unmistakable in its porticoed grandeur. We were very near the Moon Gate; due to the city's orientation, this end of Canopus Street lay quite close to the sea. The horse picked up speed. I saw Diogenes glance back over his shoulder. I ducked into the portico. When I dodged back out through the columns, I had lost him.

He could not have got far. I nipped along, trying to catch him up. Very soon, I saw the cart, recognisable by its load of scroll boxes. The horse was standing still, the driver's seat was empty. Six feet away from the cart, someone else had abandoned a donkey.

My heart thumped unevenly.

XLIX.

When completely stuck, ask pa.s.sers-by. 'Did you see where this driver went?'

'That way!To the market.'

Simple.

'And the men off the donkey?'

'That way too.'

'Walking?'

'Walking.All walking.'

'Very fast?'

'Not fast.'

Never impose unnecessary complications. People often try to impede investigations. But if they don't know who you are, they will often help.

I asked the man to keep the cart and its load safe in his yard at the back of his shop. I gave him money and promised more. If he was kind-hearted he might even feed the horse. 'Someone will come tomorrow.'

'What are these?' he gestured to the scroll boxes.

'Just some old fish-wrappers.'

'Oh - dirty stories!'

He thought it was my private h.o.a.rd of p.o.r.nography. Apparently my grinning helper had met Roman travellers with scroll collections before.

I rushed after Diogenes and his two mysterious trackers. When I caught up, he was moving along briskly, but as if he was disguising the fact he was trying to get away. The men in desert clothes were following about five strides behind, one on each side of the road. I kept them all under observation until Diogenes. .h.i.t the agora.

The market lay close to the heptastadion, the Pharos causeway. It was a huge square enclosure, open to the skies, as large as you would expect in a city devoted to international commerce, which had been established by a Greek. They love their markets. Since Alexandria was a city that hardly slept, most of the stallholders were still working. A rich odour of street food hung like a smoky cloud above the area. Shouts resounded. Wheels rattled. Footloose musicians, barefoot and threadbare, pattered on hand drums and tooted peculiar pipes. It was well-lit and vibrant, somewhere that a trader who knew his way around the city, might well feel he could lose a couple of wild men in dark cloaks who were hara.s.sing him.

At first it only looked like a man moving fast between the stalls, with others perhaps trying to catch his attention so they could all go for a drink. I was bemused but game. Where they went, I followed.

Soon it became more sinister. Diogenes began to show panic. Dropping all pretence that he was just walking somewhere and had not noticed any pursuit, he knocked into the corners of a couple of the stalls; he clattered through a pile of metal cauldrons; he kicked aside giant sponges; he annoyed people; he was chased by dogs. I fixed on him. One or other of the two men in cloaks was visible from time to time. It became apparent they were stalking Diogenes as if it was a game. They could have caught him at any time, but they were teasing - they let him think he had lost them, then swooped bat-like out of nowhere, so just as his heart started to settle, he had to be off again.

I suspected Diogenes knew them. He certainly knew what they wanted. The way he had taken off, abandoning the precious scrolls, said it all. A man who had struck me as afraid of nothing was now extremely worried.

The pursuers worked well in tandem. They seemed close-bonded. Perhaps they were Rhakotis residents, or perhaps they had fished and hunted wildfowl together in the great reed-beds of Lake Mareotis. Perhaps they came from those houseboats, where the driver had told Helena and me murderous gangs lived, unchecked by the authorities.

People began to notice the chase. The few women present gathered their children and hurried away, as if they feared trouble. Men stood and watched, though guardedly. Roaming dogs were harshly ordered back. One or two then stood by their owners' stalls, barking defiantly. A man caught my arm and pulled me to a halt; he shook his head, wagging a finger to warn me not to involve myself. I broke free and heard him mutter a baleful comment as I went on.

I saw a flash of red: soldiers. They were making their way towards Diogenes, though more curious than purposeful. A man with a great basket of apples barged into their way, perhaps deliberately, and sent fruit bowling crazily in all directions; the soldiers just stood there while he let out a cascade of complaint. If Diogenes spotted the military, he made no attempt to appeal for help. He was near enough, but instead moved on. One of his pursuers appeared, but Diogenes grabbed the awning ropes of a tunic stall, heaving over the whole edifice to block the man; entangled in garments, he let Diogenes flee. I jumped over a display of ceramic bowls, tripped on wet vegetable leaves, dodged around the end of a long row of ornament stalls, forcing a path through the crowds as best I could. When I lost sight of Diogenes, I kept going forwards and I had him in clear sight when he made what seemed to me a big mistake: ducking his head and running at a lope, he left the market on the seaward side. He set off down the enormous causeway, the heptastadion. I was so close at that point, I even yelled his name. He looked back, his face anxious, then turned away and speeded up.

The heptastadion looked long enough in daylight; it must be almost half the distance of the city north to south. I was tired, and this chase was not of my making. I decided to return to the agora and alert the soldiers. Let them catch Diogenes. Legionaries could put a roadblock on the causeway and flush out the fugitive at their leisure.

What stopped me was a dark huddle of men outside the agora gate. The rough inhabitants of Rhakotis had answered some call; they were drifting in and suddenly I saw that the gathering was being orchestrated by the two cloaked figures who had chased Diogenes. They were gesturing in his direction as he headed out across the long mole. Poor as they were, I knew the descendants of the scroll pirates would be armed - and vicious. Uncle Fulvius said they were considered very dangerous. When the first few began to make a move, I turned back and on to the causeway.

With no real plan - was I warning him, helping him or hunting him down myself? - I too began running down the heptastadion after Diogenes.

It was a serious hike. The mole was a man-made granite structure, easily as long as its name said: seven stades. At least it was good underfoot. On it ran a decent road, well built to take the fuel convoys for the Pharos and the many daily tourists. Now, in the dark, it seemed almost deserted. Diogenes took it steadily. So did I. So too did the desperadoes behind us. To anybody watching from the sh.o.r.e, or from the packed vessels in the huge Western and Eastern Harbours, we must have looked strung out like a group of athletes in a Pan-Athenian race stadium. We adopted that steady, long-distance pace marathon runners have, saving ourselves at this stage, n.o.body yet making his move to overtake.

It was a wonderful night. A cool breeze was in our faces, the sky now dark overhead but fizzing with a mult.i.tude of tiny stars. Thousands of ships were moored to right and left of us, dark hulks whose rigging made interminable noises, their b.u.mboats splashing and b.u.mping against them in the gently lapping harbour waters. Occasional cries sounded from the dark sh.o.r.e or indignant seabirds let out squawks as their privacy was disturbed. It was too late for casual strollers. If there were lovers or fishermen out there in the gloom, they lay low and kept quiet. On the far side of the Eastern Harbour, I made out buildings faintly lit - the palaces, administrative quarters and other monuments where no one made economies in lamp oil. Any junkets, recitals or concerts would now have ended. Only night-watchmen would be walking the silent marble corridors, though perhaps in some lonely room, by light from a fine wax candelabrum, the Prefect wrote his interminable reports on nothing, to let the Emperor believe he did some work.

I could have been a clerk. I could have allocated sacks and scrawled on dockets. I really could have been a poet. I would have been a poor man, with starving children, but danger would never have approached me...

I stopped thinking.

Down seven stadiums' length we ran, until breathing hurt my chest and my legs felt as heavy as waterlogged wood. I reached Pharos Island. Everywhere was dark. I could no longer see Diogenes. The road forked. Somewhere to the left was a Temple of Poseidon, the great sea G.o.d of Greece and Rome, guarding the Western Harbour's entrance. To the right lay another temple, that of Isis Pharea, the Egyptian protectress of ships. Beyond her, was stationed the Lighthouse, forming the mighty endstop. I went right. The Lighthouse, which must be manned at night, seemed the less lonely destination.

Pharos Island was a curved rocky outcrop, far enough beyond the city to feel like a wild citadel out in the thundering seas that famously beat upon the long, low sh.o.r.es of Egypt. Here, Homer said, Menelaus and Helen were beached during their journey home after the fall of Troy; at that time they found only a lonely fishing village on the island, with seals basking on the rocks. Apart from the Lighthouse, the place seemed uninhabited now, though I could not bank on it.

At the Temple of Isis, I glanced in just in case the fugitive had sought sanctuary. All lay still. No parades of priests in long white robes, no sistrums sounding, no chants. An enormous statue of Isis, big-breasted and striding forwards, held a swelling sail in front of her to symbolise catching the winds for sailors' benefit. The dim, lonely interior began to unnerve me. I left.

Ahead of me rose the enclosure for the great tower. The Pharos itself had been built as a tall, slim eagerly sought landmark for sailors to aim at from far away, one clear point in an otherwise famously unmarked coastline. It was taller than other lighthouses, perhaps the tallest structure in the world - fully five hundred feet. The walls of its square enclosure were dwarfed by the Pharos within, though when I crept up to one of the long landward sides I found those walls were formed of enormous ramparts with huge gates and corner towers.

Helena had told me how the entrepreneur who organised the twelve years of building had sneakily outwitted a regulation that forbade leaving his personal mark. He had an inscription carved on the eastern walls; on a covering layer of plaster he proclaimed the customary praise for the Pharaoh: when the weather-beaten plaster ultimately peeled off, black twenty-inch letters said: Sostratus, son of Dexiphanes, the Cnidian, dedicated this to the Saviour G.o.ds, for the seafarers. Sostratus, son of Dexiphanes, the Cnidian, dedicated this to the Saviour G.o.ds, for the seafarers. I hoped his protection would extend to me. I hoped his protection would extend to me.

The Pharos was a civic building, frequented by workers who tended the fire and even by sightseers. Its entrance was occupied by only a couple of Roman soldiers. Diogenes had got past them. The guards were chatting with their boots on a table when I burst in. I introduced myself as an imperial agent, a.s.sured them I was neither drunk nor crazy, and warned them to expect trouble. One, named Tiberius, made an effort to appear alert.

'An unruly crowd is galloping here from Rhakotis. Call for backup!' I ordered. 'Send your oppo if you have to - can you communicate with the mainland?'

'We are are at the world's biggest signal tower!' Tiberius commented sarcastically. 'Yes, sir. We can send a message - it anybody over there is looking in our direction, we can talk to them quite chattily... t.i.tus! Find the torches. Signal at the world's biggest signal tower!' Tiberius commented sarcastically. 'Yes, sir. We can send a message - it anybody over there is looking in our direction, we can talk to them quite chattily... t.i.tus! Find the torches. Signal Send reinforcements.' Send reinforcements.' He sounded ready to help. Out here among the endless sea spray, any excitement was welcome. 'This will be my first riot! What's up in Rhakotis?' He sounded ready to help. Out here among the endless sea spray, any excitement was welcome. 'This will be my first riot! What's up in Rhakotis?'

'Not sure - lock up, if you can.'

'Oh I can lock up, tribune - though I'll be locking in the workers who mostly come from Rhakotis themselves.'

'Do your best.'

I limped through the gatehouse to the vast courtyards, where forty-foot-high statues of pharaohs and their queens in colossal pairs dominated the scene. Movement caught my eye: a dwarfish figure I thought was Diogenes. He was climbing the huge ramp into the main tower.

The entrance door was set a couple of storeys above ground level, for defensive reasons. A long ramp, supported on arches, led steeply up. When I myself reached the top, gasping, I found that a wooden bridge crossed from the ramp to the door. I was already feeling afraid of heights - and I had hardly started yet. The doorway was nearly forty feet high, its architraves faced in cla.s.sic pink Egyptian granite. The same pink granite had been used elsewhere, an aesthetic contrast to much of the rest of the building, which was composed of t.i.tanic blocks of white, grey-veined Aswan marble.

The first tier of the building was an enormous square structure, aligned to the four quarters of the compa.s.s. Looking up, I could see it was topped by a huge decorated cornice that seemed to replicate the waves that I could hear pounding the outer walls, with ma.s.sive tritons blowing their horns from each corner. This great tower tapered slightly, for stability. Above it stood a second tier, which was octagonal, and high above that, the circular fire tower, crowned with a tremendous statue. Row after row of rectangular windows must light the interior; I could not stop to count but it looked as though there might be nearly twenty floors in the first tier alone.

When I went inside I found that the interior was a vast s.p.a.ce dominated by a central core that bore the weight of the upper storeys. There was what seemed to be accommodation for the keepers just inside the door. They resented disturbance, but unlike the soldiers they could pretend not to understand any languages I tried out. I could get no sense out of them.

I knew the bas.e.m.e.nt housed stores for arms and corn. This place was vast enough to house several legions, if threatened. But currently there was no permanent garrison.

Long ramps wound up the inside walls. Up those ramps, which were wide enough for four beasts abreast, trains of donkeys toiled slowly, taking combustible materials for the light - wood, with which Egypt was poorly supplied, mighty round amphorae of oil and bales of reeds as supplementary fuel. Once they reached the top of the grand spiral, they unloaded, turned around and plodded back down again.

Nothing for it. I climbed to the top of the first, square tower. It was much the largest stage. The donkeys stopped here. Men unloaded their heavy packs and took the fuel manually up the remaining distance. I climbed to the top of the first, square tower. It was much the largest stage. The donkeys stopped here. Men unloaded their heavy packs and took the fuel manually up the remaining distance.

Doors led out on to a big, railed observation platform running round the exterior. Food and drink were being sold to visitors - of whom I found more than I expected. The view was staggering. On one side was the distant sweep of the city, faintly picked out by the glimmer of thousands of tiny lights. On the other, the dark emptiness of the Mediterranean, its ominous night presence confirmed by the sounds of fierce surf breaking on the rocks far below us.

Up here were lamps, men with trays, guides spouting facts and figures, and a festival atmosphere. I had never been anywhere like it that was man-made. The Lighthouse had always been a tourist attraction. Even at night, supper parties must come out here in fine weather. Rich fathers arranged birthday and wedding celebrations. Ordinary families came sightseeing, for education, fun and striking memories. There were people up here now - not throngs, but enough to make it dangerous if Diogenes had brought trouble - enough people for me to have lost sight of him and not to know either whether his two cloaked pursuers had followed him this far.

I walked around, on the way meeting Tiberius, the tough soldier from the gatehouse, together with t.i.tus, his companion, who was carrying signal torches and what I recognised as the codebook. We failed to find Diogenes at this level, so while the soldiers cleared a s.p.a.ce on the viewing platform and began to send their message sh.o.r.eward, I left them to it, gritted my teeth and began to climb up inside the next tier.

L.

Now I was making my way up the octagon. By the time I staggered out on to the next viewing platform, I was nearly done in. For those who wanted to make this additional climb to the top of the eight-sided tower, and who could find the stamina, a smaller balcony gave a truly spectacular view. This must be over three hundred feet above the sea. It was wonderful and horrific at the same time. Anyone here needed a head for heights that I unfortunately lacked.

Far down below in the courtyard, men swarmed like insects. On the wind came faint ululating cries. I had heard such sounds in terrible places and situations - the rebellion in Britain was the worst; remembering, I shuddered. As I leaned over, way down there on the ramp to the main door, it looked as if one scarlet blob - Tiberius? - held the riot at bay, a latter-day Horatius defending the wooden bridge. If I made it out correctly, as men from Rhakotis ran across sporadically, they were whacked and tipped off the ramp. The spectacle added to the madness of this unexpected night.

On the first viewing platform below me, I saw the soldier t.i.tus diligently shepherding the public inside the tower for safety. On his own, he was not having much luck. People were milling about hopelessly, of course.

Drawn by the crackle of the great fire, I climbed into the cylindrical lantern area, just as a bunch of the stokers came pushing out in panic. Not waiting to say what disturbed them, they scattered down the octagon.

At the top, I found a frightening scene. I had entered the eerie, perpetually mobile, orange light of the beacon. A strong steady wind blew constantly, its noise lost in the roar of the fire. I was sure I could feel movement. The lantern tower was substantial but it seemed to sway.

The Pharos had stood here for three hundred and fifty years - but the Greeks and Egyptians never had a beacon fire. It was our introduction; we Romans added it, because ever-increasing night-time sea traffic required better safety features. Ca.s.sius had given my children a model lantern, which they loved and used as a nightlight. That showed the ancient design; it was topped by a pillared tower, covered by a cupola - a feature that still lived in folk memory and would probably persist. But to accommodate a ma.s.sive fire-basket, which had to be open to the skies, the round turret's root had now been dismantled. The open top of the Pharos glowed like a lurid scene from Vulcan's forge, with dark figures tending the terrific fire.

On my face I felt the burning heat, a blaze so fierce it was barely approachable. You wouldn't toast your lunch bap here. Sweating stokers tended the fire with long metal rakes. Behind, from my viewpoint, stood an enormous curved metal reflector. Mirror-bright, it gleamed red in the light of the beacon. From out to sea, some said a hundred miles away, this light would shine like a huge star, low on the horizon, bringing hope for anxious sailors and a dramatic statement of Alexandria's power and prestige.

To my astonishment, I made out Diogenes. Even more out of breath than me, he had staggered to the foot of a colossal statue, a leftover that had once topped the old covered tower - Zeus? Poseidon? One of the heavenly twins, Castor and Pollux? It was no moment for art appreciation. Diogenes was slumped and on the verge of collapse.

Suddenly, from behind the reflector leapt one of his tormentors. Bat-like and shrieking, the wild figure ran at the trader. Diogenes stumbled to his feet, trying to flee. Cowering away from the cloaked figure, he tipped over a low wall that contained the beacon and fell right into the roaring flames. He began to scream. Ablaze from head to foot, he floundered there; but it can only have been moments before he desperately clambered out. Intentionally or not, he launched himself towards his a.s.sailant, a fiery human torch. The man in black lost his cloak as he tried to get away. Holding up an arm to shield his face from the beacon's hot glare, he ran blind. He crashed against the outer balcony parapet. Unable to regain his balance, his momentum toppled him right over. His cry was lost as he vanished.

Diogenes fell to the ground. His clothes, hair and skin were alight. By the time I reached him, a stoker had aimed the contents of a fire-bucket over the writhing figure, but in that great heat the water sizzled uselessly. We dragged the attacker's discarded cloak over the p.r.o.ne man, then people brought more water pails. But some fool pulled the cloak away, so the flames broke out again spontaneously. At last stokers dragged up a heavy fire-mat and rolled Diogenes in it; they must have had experience or training. He was still alive when we finally put him out, but his burns were so bad he could never survive. Ghastly shreds of skin from his back and arms just fell away. I doubted he would even make the journey down to ground level.

Sickened, I crouched beside him. 'Diogenes! Can you hear me? Who were those men? What did they want you for?' He mumbled. Someone put a flask to his charred lips. Most of the liquid ran away down his neck. He struggled to speak. I strained to hear.

'Stuff you, Falco!'

He sank into unconsciousness. Despairing, I left the stokers to bring the body down.

I stumbled my way off the fire tower and back down the octagon. When I reached the public viewing platform at the top of the big main tower, it seemed deserted. I felt cold and desolate. This night had turned as sour as it could be - and still gave me no answers.

People who had been shepherded into the interior were crowding on the spiral ramps. White-faced, they gazed upwards in terror, aware that some tragedy had unfolded high above.

'Everyone stay inside, please - for your own safety. Make your way quietly down to the bottom now. Leave this to us!' One of the soldiers, t.i.tus, came out on to the platform with me. We took lamps and searched the four long sides of the observatory area. Together we found the motionless form of the man who had gone over.

t.i.tus bent. 'He's done for.' He twisted and looked up at the lantern, high above us. 'Must be what - eighty feet?' Who knows? He was guessing. 'No chance.'

'There was another man.'

'Must have scrammed.'

t.i.tus moved back. I bent to inspect the dead man's face. 'What?' 'What?'

'Know him, Falco?'

'That's unbelievable... He works at the Museion zoo.' I looked twice, but there was no doubt. It was either Chaereas or Chaeteas. That took some comprehending. Whatever had turned those two calm, competent zoo a.s.sistants into vengeful furies, hunting a man to his death? Risking their own lives to do it, too. 'I'll have to go after the one who's made a run tor it - how can I get out of the building safely? Are those rioters in the courtyard?'

'All be sorted by the time you reach the door. 't.i.tus looked over to confirm: I joined him, though with trepidation. My nerve had vanished up on these windy platforms where I had just seen two men die.