Pompeii

POMPEII

ROBERT HARRIS

Random House New York

AUTHOR’S NOTE

The Romans divided the day into twelve hours. The first,hora prima, began at sunrise. The last,hora duodecima, ended at sunset.

The night was divided into eight watches—Vespera, Prima fax, Concubia,andIntempesta before midnight;Inclinatio, Gallicinium, Conticinium, andDiluculum after it.

The days of the week were Moon, Mars, Mercury, Jupiter, Venus, Saturn, and Sun.

Pompeii takes place over four days.

Sunrise on the Bay of Naples in the fourth week of AugustA.D. 79 was at approximately 06:20 hours.

MARS

22 August

Two days before the eruption

CONTICINIUM

[04:21 hours]

A strong correlation has been found between the

magnitude of eruptions and the length of the preceding

interval of repose. Almost all very large, historic eruptions have

come from volcanoes that have been dormant for centuries.

—JACQUES-MARIE BARDINTZEFF, ALEXANDER R. McBIRNEY

VOLCANOLOGY (SECOND EDITION)

They left the aqueduct two hours before dawn, climbing by moonlight into the hills overlooking the port—six men in single file, the engineer leading. He had turned them out of their beds himself—all stiff limbs and sullen, bleary faces—and now he could hear them complaining about him behind his back, their voices carrying louder than they realized in the warm, still air.

“A fool’s errand,” somebody muttered.

“Boys should stick to their books,” said another.

He lengthened his stride.

Let them prattle, he thought.

Already he could feel the heat of the morning beginning to build, the promise of another day without rain. He was younger than most of his work gang, and shorter than any of them: a compact, muscled figure with cropped brown hair. The shafts of the tools he carried slung across his shoulder—a heavy, bronze-headed axe and a wooden shovel—chafed against his sunburned neck. Still, he forced himself to stretch his bare legs as far as they would reach, mounting swiftly from foothold to foothold, and only when he was high above Misenum, at a place where the track forked, did he set down his burdens and wait for the others to catch up.

He wiped the sweat from his eyes on the sleeve of his tunic. Such shimmering, feverish heavens they had here in the south! Even this close to daybreak, a great hemisphere of stars swept down to the horizon. He could see the horns of Taurus, and the belt and sword of the Hunter; there was Saturn, and also the Bear, and the constellation they called the Vintager, which always rose for Caesar on the twenty-second day of August, following the Festival of Vinalia, and signaled that it was time to harvest the wine. Tomorrow night the moon would be full. He raised his hand to the sky, his blunt-tipped fingers black and sharp against the glittering constellations—spread them, clenched them, spread them again—and for a moment it seemed to him that he was the shadow, the nothing; the light was the substance.

From down in the harbor came the splash of oars as the night watch rowed between the moored triremes. The yellow lanterns of a couple of fishing boats winked across the bay. A dog barked and another answered. And then the voices of the laborers slowly climbing the path beneath him: the harsh local accent of Corax, the overseer—“Look, our new aquarius is waving at the stars!”—and the slaves and the free men, equals, for once, in their resentment if nothing else, panting for breath and sniggering.

The engineer dropped his hand. “At least,” he said, “with such a sky, we have no need of torches.” Suddenly he was vigorous again, stooping to collect his tools, hoisting them back onto his shoulder. “We must keep moving.” He frowned into the darkness. One path would take them westward, skirting the edge of the naval base. The other led north, toward the seaside resort of Baiae. “I think this is where we turn.”

“He thinks,” sneered Corax.

The engineer had decided the previous day that the best way to treat the overseer was to ignore him. Without a word he put his back to the sea and the stars, and began ascending the black mass of the hillside. What was leadership, after all, but the blind choice of one route over another and the confident pretense that the decision was based on reason?

The path here was steeper. He had to scramble up it sideways, sometimes using his free hand to pull himself along, his feet skidding, sending showers of loose stones rattling away in the darkness. People stared at these brown hills, scorched by summer brushfires, and thought they were as dry as deserts, but the engineer knew different. Even so, he felt his earlier assurance beginning to weaken, and he tried to remember how the path had appeared in the glare of yesterday afternoon, when he had first reconnoitered it. The twisting track, barely wide enough for a mule. The swaths of scorched grass. And then, at a place where the ground leveled out, flecks of pale green in the blackness—signs of life that turned out to be shoots of ivy reaching toward a boulder.

After going halfway up an incline and then coming down again, he stopped and turned slowly in a full circle. Either his eyes were getting used to it, or dawn was close now, in which case they were almost out of time. The others had halted behind him. He could hear their heavy breathing. Here was another story for them to take back to Misenum—how their new young aquarius had dragged them from their beds and marched them into the hills in the middle of the night, and all on a fool’s errand . There was a taste of ash in his mouth.

“Are we lost, pretty boy?”

Corax’s mocking voice again.

He made the mistake of rising to the bait: “I’m looking for a rock.”

This time they did not even try to hide their laughter.

“He’s running around like a mouse in a pisspot!”

“I know it’s here somewhere. I marked it with chalk.”

More laughter—and at that he wheeled on them: the squat and broad-shouldered Corax; Becco, the long-nose, who was a plasterer; the chubby one, Musa, whose skill was laying bricks; and the two slaves, Polites and Corvinus. Even their indistinct shapes seemed to mock him. “Laugh. Good. But I promise you this: either we find it before dawn or we shall all be back here tomorrow night. Including you, Gavius Corax. Only next time make sure you’re sober.”

Silence. Then Corax spat and took a half step forward and the engineer braced himself for a fight. They had been building up to this for three days now, ever since he had arrived in Misenum. Not an hour had passed without Corax trying to undermine him in front of the men.

And if we fight, thought the engineer, he will win—it’s five against one—and they will throw my body over the cliff and say I slipped in the darkness. But how will that go down in Rome—if a second aquarius of the Aqua Augusta is lost in less than a fortnight?

For a long instant they faced each other, no more than a pace between them, so close that the engineer could smell the stale wine on the older man’s breath. But then one of the others—it was Becco—gave an excited shout and pointed.

Just visible behind Corax’s shoulder was a rock, marked neatly in its center by a thick white cross.

Attilius was the engineer’s name—Marcus Attilius Primus, to lay it out in full, but plain Attilius would have satisfied him. A practical man, he had never had much time for all these fancy handles his fellow countrymen went in for. (“Lupus,” “Panthera,” “Pulcher”—“Wolf,” “Leopard,” “Beauty”—who in hell did they think they were kidding?) Besides, what name was more honorable in the history of his profession than that of the gens Attilia, aqueduct engineers for four generations? His great-grandfather had been recruited by Marcus Agrippa from the ballista section of Legion XII “Fulminata” and set to work building Rome’s Aqua Julia. His grandfather had planned the Anio Novus. His father had completed the Aqua Claudia, bringing her into the Esquiline Hill over seven miles of arches, and laying her, on the day of her dedication, like a silver carpet at the feet of the emperor. Now he, at twenty-seven, had been sent south to Campania and given command of the Aqua Augusta.

A dynasty built on water!

He squinted into the darkness. Oh, but she was a mighty piece of work, the Augusta—one of the greatest feats of engineering ever accomplished. It was going to be an honor to command her. Somewhere far out there, on the opposite side of the bay, high in the pine-forested mountains of the Apenninus, the aqueduct captured the springs of Serinus and bore the water westward—channeled it along sinuous underground passages, carried it over ravines on top of tiered arcades, forced it across valleys through massive siphons—all the way down to the plains of Campania, then around the far side of Mount Vesuvius, then south to the coast at Neapolis, and finally along the spine of the Misenum peninsula to the dusty naval town, a distance of some sixty miles, with a mean drop along her entire length of just two inches every one hundred yards. She was the longest aqueduct in the world, longer even than the great aqueducts of Rome and far more complex, for whereas her sisters in the north fed one city only, the Augusta’s serpentine conduit—the matrix, as they called it: the motherline—suckled no fewer than nine towns around the Bay of Neapolis: Pompeii first, at the end of a long spur, then Nola, Acerrae, Atella, Neapolis, Puteoli, Cumae, Baiae, and finally Misenum.

And this was the problem, in the engineer’s opinion. She had to do too much. Rome, after all, had more than half a dozen aqueducts: if one failed the others could make up the deficit. But there was no reserve supply down here, especially not in this drought, now dragging into its third month. Wells that had provided water for generations had turned into tubes of dust. Streams had dried up. Riverbeds had become tracks for farmers to drive their beasts along to market. Even the Augusta was showing signs of exhaustion, the level of her enormous reservoir dropping hourly, and it was this that had brought him out onto the hillside in the time before dawn when he ought to have been in bed.

From the leather pouch on his belt Attilius withdrew a small block of polished cedar with a chin rest carved into one side of it. The grain of the wood had been rubbed smooth and bright by the skin of his ancestors. His great-grandfather was said to have been given it as a talisman by Vitruvius, architect to the Divine Augustus, and the old man had maintained that the spirit of Neptune, god of water, lived within it. Attilius had no time for gods. Boys with wings on their feet, women riding dolphins, greybeards hurling bolts of lightning off the tops of mountains in fits of temper—these were stories for children, not men. He placed his faith instead in stones and water, and in the daily miracle that came from mixing two parts of slaked lime to five parts of puteolanum—the local red sand—conjuring up a substance that would set underwater with a consistency harder than rock.

But still—it was a fool who denied the existence of luck, and if this family heirloom could bring him that . . . He ran his finger around its edge. He would try anything once.

He had left his rolls of Vitruvius behind in Rome. Not that it mattered. They had been hammered into him since childhood, as other boys learned their Virgil. He could still recite entire passages by heart.

“These are the growing things to be found which are signs of water: slender rushes, wild willow, alder, chaste berry, ivy, and other things of this sort, which cannot occur on their own without moisture . . .”

“Corax over there,” ordered Attilius. “Corvinus there. Becco, take the pole and mark the place I tell you. You two: keep your eyes open.”

Corax gave him a look as he passed.

“Later,” said Attilius. The overseer stank of resentment almost as strongly as he reeked of wine, but there would be time enough to settle their quarrel when they got back to Misenum. For now they would have to hurry.

A gray gauze had filtered out the stars. The moon had dipped. Fifteen miles to the east, at the midpoint of the bay, the forested pyramid of Mount Vesuvius was becoming visible. The sun would rise behind it.

“This is how to test for water: lie face down, before sunrise, in the places where the search is to be made, and with your chin set on the ground and propped, survey these regions. In this way the line of sight will not wander higher than it should, because the chin will be motionless . . .”

Attilius knelt on the singed grass, leaned forward, and arranged the block in line with the chalk cross, fifty paces distant. Then he set his chin on the rest and spread his arms. The ground was still warm from yesterday. Particles of ash wafted into his face as he stretched out. No dew. Seventy-eight days without rain. The world was burning up. At the fringe of his eye line he saw Corax make an obscene gesture, thrusting out his groin—“Our aquarius has no wife, so he tries to fuck Mother Earth instead!”—and then, away to his right, Vesuvius darkened and light shot from the edge of it. A shaft of heat struck Attilius’s cheek. He had to bring up his hand to shield his face from the dazzle as he squinted across the hillside.

“In those places where moisture can be seen curling and rising into the air, dig on the spot, because this sign cannot occur in a dry location . . .”

You saw it quickly, his father used to tell him, or you did not see it at all. He tried to scan the ground rapidly and methodically, shifting his gaze from one section of the land to the next. But it all seemed to run together—parched browns and grays and streaks of reddish earth, already beginning to waver in the sun. His vision blurred. He raised himself on his elbows and wiped each eye with a forefinger and settled his chin again.

There!

As thin as a fishing line it was—not “curling” or “rising” as Vitruvius promised, but snagging, close to the ground, as if a hook were caught on a rock and someone were jerking it. It zigzagged toward him. And vanished. He yelled and pointed—“There, Becco, there!”—and the plasterer lumbered toward the spot. “Back. Yes. There. Mark it.”

He scrambled to his feet and hurried toward them, brushing the red dirt and black ash from the front of his tunic, smiling, holding the magical block of cedar aloft. The three had gathered around the place and Becco was trying to jam the pole into the earth, but the ground was too hard to sink it far enough.

Attilius was triumphant. “You saw it? You must have seen it. You were closer than I.”

They stared at him blankly.

“It was curious, did you notice? It rose like this.” He made a series of horizontal chops at the air with the flat of his hand. “Like steam coming off a cauldron that’s being shaken.”

He looked from one to another, his smile fixed at first, then shrinking.

Corax shook his head. “Your eyes are playing tricks on you, pretty boy. There’s no spring up here. I told you. I’ve known these hills for twenty years.”

“And I’m telling you I saw it.”

“Smoke.” Corax stamped his foot on the dry earth, raising a cloud of dust. “A brushfire can burn underground for days.”

“I know smoke. I know vapor. This was vapor.”

They were shamming blindness. They had to be. Attilius dropped to his knees and patted the dry red earth. Then he started digging with his bare hands, working his fingers under the rocks and tossing them aside, tugging at a long, charred tuber which refused to come away. Something had emerged from here. He was sure of it. Why had the ivy come back to life so quickly if there was no spring?

He said, without turning round, “Fetch the tools.”

“Aquarius—”

“Fetch the tools!”

They dug all morning, as the sun climbed slowly above the blue furnace of the bay, melting from yellow disk to gaseous white star. The ground creaked and tautened in the heat, like the bowstring of one of his great-grandfather’s giant siege engines.

Once, a boy passed them, dragging an emaciated goat by a rope halter toward the town. He was the only person they saw. Misenum itself lay hidden from view just beyond the cliff edge. Occasionally its sounds floated up to them—shouts of command from the military school, hammering and sawing from the shipyards.

Attilius, an old straw hat pulled low over his face, worked hardest of all. Even when the others crept off occasionally to sprawl in whatever patches of shade they could find, he continued to swing his ax. The shaft was slippery with his sweat and hard to grip. His palms blistered. His tunic stuck to him like a second skin. But he would not show weakness in front of the men. Even Corax shut up after a while.

The crater they eventually excavated was twice as deep as a man’s height, and broad enough for two of them to work in. And there was a spring there, right enough, but it retreated whenever they came close. They would dig. The rusty soil at the bottom of the hole would turn damp. And then it would bake dry again in the sunlight. They would excavate another layer and the same process would recur.

Only at the tenth hour, when the sun had passed its zenith, did Attilius at last acknowledge defeat. He watched a final stain of water dwindle and evaporate, then flung his ax over the lip of the pit and hauled himself after it. He pulled off his hat and fanned his burning cheeks. Corax sat on a rock and watched him. For the first time Attilius noticed he was bareheaded.

He said, “You’ll boil your brains in this heat.” He uncorked his waterskin and tipped a little into his hand, splashed it onto his face and the back of his neck, then drank. It was hot—as unrefreshing as swallowing blood.

“I was born here. Heat doesn’t bother me. In Campania we call this cool.” Corax hawked and spat. He tilted his broad chin toward the hole. “What do we do with this?”

Attilius glanced at it—an ugly gash in the hillside, great mounds of earth heaped all around it. His monument. His folly. “We’ll leave it as it is,” he said. “Have it covered with planks. When it rains, the spring will rise. You’ll see.”

“When it rains, we won’t need a spring.”

A fair point,Attilius had to concede.

“We could run a pipe from it,” he said thoughtfully. He was a romantic when it came to water. In his imagination, a whole pastoral idyll suddenly began to take shape. “We could irrigate this entire hillside. There could be lemon groves up here. Olives. It could be terraced. Vines—”

“Vines!” Corax shook his head. “So now we’re farmers! Listen to me, young expert from Rome. Let me tell you something. The Aqua Augusta hasn’t failed in more than a century. And she isn’t going to fail now. Not even with you in charge.”

“We hope.” The engineer finished the last of his water. He could feel himself blushing scarlet with humiliation, but the heat hid his shame. He planted his straw hat firmly on his head and pulled down the brim to protect his face. “All right, Corax, get the men together. We’ve done here for the day.”

He collected his tools and set off without waiting for the others. They could find their own way back.

He had to watch where he put his feet. Each step sent a scattering of lizards rustling away into the dry undergrowth.It’s more Africa than Italy, he thought, and when he reached the coastal path, Misenum appeared beneath him, shimmering in the haze of heat like an oasis town, pulsing—or so it seemed to him—in time with the cicadas.

The headquarters of the western imperial fleet was a triumph of man over nature, for by rights no town should exist here. There was no river to support her, few wells or springs. Yet the Divine Augustus had decreed that the empire needed a port from which to control the Mediterranean, and here she was, the embodiment of Roman power: the glittering silver disks of her inner and outer harbors, the golden beaks and fantail sterns of fifty warships glinting in the late-afternoon sun, the dusty brown parade ground of the military school, the red-tiled roofs and the whitewashed walls of the civilian town rising above the spiky forest of masts in the shipyard.

Ten thousand sailors and another ten thousand citizens were crammed into a narrow strip of land with no fresh water to speak of. Only the aqueduct had made Misenum possible.

He thought again of the curious motion of the vapor, and the way the spring had seemed to run back into the rock. A strange country, this. He looked ruefully at his blistered hands.

“A fool’s errand.”

He shook his head, blinking his eyes to clear them of sweat, and resumed his weary trudge down to the town.

HORA UNDECIMA

[17:42 hours]

A question of practical importance to forecasting is how much time elapses between an injection of new magma and an ensuing eruption. In many volcanoes, this time interval may be measured in weeks or months,

but in others it seems to be much shorter, possibly days or hours.

—VOLCANOLOGY(SECOND EDITION)

At the Villa Hortensia, the great coastal residence on the northern outskirts of Misenum, they were preparing to put a slave to death. They were going to feed him to the eels. It was not an unknown practice in that part of Italy, where so many of the huge houses around the Bay of Neapolis had their own elaborate fish farms. The new owner of the Villa Hortensia, the millionaire Numerius Popidius Ampliatus, had first heard the story as a boy—of how the Augustan aristocrat Vedius Pollio would hurl clumsy servants into his eel pond as a punishment for breaking dishes—and he would often refer to it admiringly as the perfect illustration of what it was to have power. Power, and imagination, and wit, and a certainstyle .

So when, many years later, Ampliatus, too, came to possess a fishery—just a few miles down the coast from Vedius Pollio’s old place at Pausilypon—and when one of his slaves also destroyed something of rare value, the precedent naturally came back into his mind. Ampliatus had been born a slave himself; this was how he thought an aristocrat ought to behave.

The poor fellow was duly stripped to his loincloth, had his hands tied behind his back, and was marched down to the edge of the sea. A knife was run down both of his calves, to draw an attractive amount of blood, and he was also doused with vinegar, which was said to drive the eels mad.

It was late afternoon, very hot.

The eels had their own large pen, built well away from the other fishponds to keep them segregated, reached by a narrow concrete gangway extending out into the bay. These eels were morays, notorious for their aggression, their bodies as long as a man’s and as wide as a human trunk, with flat heads, wide snouts, and razor teeth. The villa’s fishery was a hundred fifty years old and nobody knew how many lurked in the labyrinth of tunnels and in the shady areas built into the bottom of the pond. Scores, certainly; probably hundreds. The more ancient eels were monsters and several wore jewelry. One, which had a gold earring fitted to its pectoral fin, was said to have been a favorite of the Emperor Nero.

The morays were a particular terror to this slave because—Ampliatus savored the irony—it had long been his responsibility to feed them, and he was shouting and struggling even before he was forced onto the gangway. He had seen the eels in action every morning when he threw in their meal of fish heads and chicken entrails—the way the surface of the water flickered, then roiled as they sensed the arrival of the blood, and the way they came darting out of their hiding places to fight over their food, tearing it to pieces.

At the eleventh hour, despite the sweltering heat, Ampliatus himself promenaded down from the villa to watch, attended by his teenaged son, Celsinus, together with his household steward, Scutarius, a few of his business clients (who had followed him from Pompeii and had been hanging around since dawn in the hope of dinner), and a crowd of about a hundred of his other male slaves who he had decided would profit by witnessing the spectacle. His wife and daughter he had ordered to remain indoors: this was not a sight for women. A large chair was set up for him, with smaller ones for his guests. He did not even know the errant slave’s name. He had come as part of a job lot with the fishponds when Ampliatus had bought the villa, for a cool ten million, earlier in the year.

All manner of fish were kept, at vast expense, along the shoreline of the house—sea bass, with their woolly-white flesh; gray mullet, which required high walls around their pond to prevent them leaping to freedom; flatfish and parrot fish and giltheads; lampreys and congers and hake.

But by far the most expensive of Ampliatus’s aquatic treasures—he trembled to think how much he had paid for them, and he did not even much like fish—were the red mullet, the delicate and whiskered goatfish, notoriously difficult to keep, whose colors ran from pale pink to orange. And it was these that the slave had killed—whether by malice or incompetence, Ampliatus did not know, nor care, but there they were: clustered together in death as they had been in life, a multihued carpet floating on the surface of their pond, discovered earlier that afternoon. A few had still been alive when Ampliatus was shown the scene, but they had died even as he watched, turning like leaves in the depths of the pool and rising to join the others. Poisoned, every one. They would have fetched six thousand apiece at current market prices—one mullet being worth five times as much as the miserable slave who was supposed to look after them—and now they were fit only for the fire. Ampliatus had pronounced sentence immediately: “Throw him to the eels!”

The slave was screaming as they dragged and prodded him toward the edge of the pool. It was not his fault, he was shouting. It was not the food. It was the water. They should fetch the aquarius.

The aquarius!

Ampliatus screwed up his eyes against the glare of the sea. It was hard to make out the shapes of the writhing slave and of the two others holding him, or of the fourth, who held a boat hook like a lance and was jabbing it into the doomed man’s back—mere stick figures, all of them, in the haze of the heat and the sparkling waves. He raised his arm in the manner of an emperor, his fist clenched, his thumb parallel with the ground. He felt godlike in his power, yet full of simple human curiosity. For a moment he waited, tasting the sensation, then abruptly he twisted his wrist and jammed his thumb upward. Let him have it!

The piercing cries of the slave teetering on the side of the eel pond carried up from the seafront, across the terraces, over the swimming pool, and into the silent house where the women were hiding.

Corelia Ampliata had run to her bedroom, thrown herself down on the mattress, and pulled her pillow over her head, but there was no escaping the sound. Unlike her father, she knew the slave’s name—Hipponax, a Greek—and also the name of his mother, Atia, who worked in the kitchens, and whose lamentations, once they started, were even more terrible than his. Unable to bear the screams for more than a few moments, she sprang up again and ran through the deserted villa to find the wailing woman, who had sunk against a column in the cloistered garden.

Seeing Corelia, Atia clutched at her young mistress’s hem and began weeping at her slippered feet, repeating over and over that her son was innocent, that he had shouted to her as he was being carried away—it was the water, the water, there was something wrong with the water. Why would nobody listen to him?

Corelia stroked Atia’s gray hair and tried to make such soothing noises as she could. There was little else that she could do. Useless to appeal to her father for clemency—she knew that. He listened to nobody, least of all to a woman, and least of all women to his daughter, from whom he expected an unquestioning obedience—an intervention from her would only make the death of the slave doubly certain. To Atia’s pleas she could only reply that there was nothing she could do.

At this, the old woman—in truth she was in her forties, but Corelia thought of slave years as being like dog years, and she appeared at least sixty—suddenly broke away and roughly dried her eyes on her arm.

“I must find help.”

“Atia, Atia,” said Corelia gently, “who will give it?”

“He shouted for the aquarius. Didn’t you hear him? I shall fetch the aquarius.”

“And where is he?”

“He may be at the aqueduct down the hill, where the watermen work.”

She was on her feet now, trembling but determined, staring around her wildly. Her eyes were red, her dress and hair disordered. She looked like a madwoman and Corelia saw at once that no one would pay her any attention. They would laugh at her, or drive her off with stones.

“I’ll come with you,” she said, and as another terrible scream rose from the waterfront Corelia gathered up her skirts with one hand, grabbed the old woman’s wrist with the other, and together they fled through the garden, past the empty porter’s stool, out of the side door, and into the dazzling heat of the public road.

The terminus of the Aqua Augusta was a vast underground reservoir, a few hundred paces south of the Villa Hortensia, hewn into the slope overlooking the port and known, for as long as anyone could remember, as the Piscina Mirabilis—the Pool of Wonders.

Viewed from the outside, there was nothing particularly wonderful about her and most of the citizens of Misenum passed her without a second glance. She appeared on the surface as a low, flat-roofed building of red brick, festooned with pale-green ivy, a city block long and half a block wide, surrounded by shops and storerooms, bars and apartments, hidden away in the dusty back streets above the naval base.

Only at night, when the noise of the traffic and the shouts of the tradesmen had fallen silent, was it possible to hear the low, subterranean thunder of falling water, and only if you went into the yard, unlocked the narrow wooden door, and descended a few steps into the piscina itself was it possible to appreciate the reservoir’s full glory. The vaulted roof was supported by forty-eight pillars, each more than fifty feet high—although most of their length was submerged by the waters of the reservoir—and the echo of the aqueduct hammering into the surface was enough to shake your bones.

The engineer could stand here, listening and lost in thought, for hours. The percussion of the Augusta sounded in his ears not as a dull and continuous roar but as the notes of a gigantic water organ: the music of civilization. There were air shafts in the piscina’s roof, and in the afternoons, when the foaming spray leaped in the sunlight and rainbows danced between the pillars—or in the evenings, when he locked up for the night and the flame of his torch shone across the smooth black surface like gold splashed on ebony—in those moments, he felt himself to be not in a reservoir at all, but in a temple dedicated to the only god worth believing in.

Attilius’s first impulse on coming down from the hills and into the yard at the end of that afternoon was to check the level of the reservoir. It had become his obsession. But when he tried the door he found it was locked and then he remembered that Corax was carrying the key on his belt. He was so tired that for once he thought no more about it. He could hear the distant rumble of the Augusta—she was running: that was all that counted—and later, when he came to analyze his actions, he decided he could not really reproach himself for any dereliction of duty. There was nothing he could have done. Events would have worked out differently for him personally, that was true—but that hardly mattered in the larger context of the crisis.

So he turned away from the piscina and glanced around the deserted yard. The previous evening he had ordered that the space be tidied and swept while he was away, and he was pleased to see that this had been done. There was something reassuring to him about a well-ordered yard. The neat stacks of lead sheets, the amphorae of lime, the sacks of puteolanum, the ruddy lengths of terra-cotta pipe—these were the sights of his childhood. The smells, too—the sharpness of the lime; the dustiness of fired clay left out all day in the sun.

He went into the stores, dropped his tools on the earth floor, and rotated his aching shoulder, then wiped his face on the sleeve of his tunic and reentered the yard just as the others trooped in. They headed straight for the drinking fountain without bothering to acknowledge him, taking turns to gulp the water and splash their heads and bodies—Corax, then Musa, then Becco. The two slaves squatted patiently in the shade, waiting until the free men had finished. Attilius knew he had lost face during the course of the day. But still, he could live with their hostility. He had lived with worse things.

He shouted to Corax that the men could finish work for the day, and was rewarded with a mocking bow, then started to climb the narrow wooden staircase to his living quarters.

The yard was a quadrangle. Its northern side was taken up by the wall of the Piscina Mirabilis. To the west and south were storerooms and the administrative offices of the aqueduct. To the east was the living accommodation: a barracks for the slaves on the ground floor and an apartment for the aquarius above it. Corax and the other free men lived in the town with their families.

Attilius, who had left his mother and sister behind in Rome, thought that in due course he would probably move them down to Misenum as well and rent a house, which his mother could keep for him. But for the time being he was sleeping in the cramped bachelor accommodation of his predecessor, Exomnius, whose few possessions he had had moved into the small spare room at the end of the passage.

What had happened to Exomnius? Naturally, that had been Attilius’s first question when he arrived in the port. But nobody had had an answer, or, if they had, they weren’t about to pass it on to him. His enquiries were met by sullen silence. It seemed that old Exomnius, a Sicilian who had run the Augusta for nearly twenty years, had simply walked out one morning more than two weeks ago and had not been heard of since.

Ordinarily, the department of the Curator Aquarum in Rome, which administered the aqueducts in regions one and two (Latium and Campania) would have been willing to let matters lie for a while. But given the drought, and the strategic importance of the Augusta, and the fact that the senate had adjourned for its summer recess in the third week of July and half its members were at their holiday villas around the bay, it had been thought prudent to dispatch an immediate replacement. Attilius had received the summons on the ides of August, at dusk, just as he was finishing off some routine maintenance work on the Anio Novus. Conducted into the presence of the Curator Aquarum himself, Acilius Aviola, at his official residence on the Palatine Hill, he had been offered the commission. Attilius was bright, energetic, dedicated—the senator knew how to flatter a man when he wanted something—with no wife or children to detain him in Rome. Could he leave the next day? And, of course, Attilius had accepted at once, for this was a great opportunity to advance his career. He had said farewell to his family and had caught the daily ferry from Ostia.

He had started to write a letter to them. It lay on the nightstand next to the hard wooden bed. He was not very good at letters. Routine information—I have arrived, the journey was good, the weather is hot—written out in his schoolboy’s hand was the best he could manage. It gave no hint of the turmoil he felt within: the pressing sense of responsibility, his fears about the water shortage, the isolation of his position. But they were women—what did they know?—and besides, he had been taught to live his life according to the Stoic school: to waste no time on nonsense, to do one’s job without whining, to be the same in all circumstances—intense pain, bereavement, illness—and to keep one’s lifestyle simple: the camp bed and the cloak.

He sat on the edge of the mattress. His household slave, Phylo, had put out a jug of water and a basin, some fruit, a loaf, a pitcher of wine, and a slice of hard white cheese. He washed himself carefully, ate all the food, mixed some wine into the water, and drank. Then, too exhausted even to remove his shoes and tunic, he lay down on the bed, closed his eyes, and slipped at once into that hinterland between sleeping and waking that his dead wife endlessly roamed, her voice calling out to him—pleading, urgent: “Aquarius! Aquarius!”

His wife had been just twenty-two when he watched her body

consigned to the flames of her funeral pyre. This woman was younger—eighteen, perhaps. Still, there was enough of the dream that lingered in his mind, and enough of Sabina about the girl in the yard for his heart to jump. The same darkness of hair. The same whiteness of skin. The same voluptuousness of figure. She was standing beneath his window and shouting up.

“Aquarius!”

The sound of raised voices had drawn some of the men from the shadows and by the time he reached the bottom of the stairs they had formed a gawping half-circle around her. She was wearing a loose white tunica, open wide at the neck and sleeves—a dress to be worn in private, which showed a little more of the milky plumpness of her bare white arms and breasts than a respectable lady would have risked in public. He saw now that she was not alone. A slave attended her—a skinny, trembling, elderly woman, whose thin gray hair was half pinned up, half tumbling down her back.

She was breathless, gabbling—something about a pool of red mullet that had died that afternoon in her father’s fishponds, and poison in the water, and a man who was being fed to the eels, and how he must come at once. It was hard to catch all her words.

He held up his hand to interrupt her and asked her name.

“I am Corelia Ampliata, daughter of Numerius Popidius Ampliatus, of the Villa Hortensia.” She announced herself impatiently and, at the mention of her father, Attilius noticed Corax and some of the men exchange looks. “Are you the aquarius?”

Corax said, “The aquarius isn’t here.”

The engineer waved him away. “I am in charge of the aqueduct, yes.”

“Then come with me.”

She began walking toward the gate and seemed surprised when Attilius did not immediately follow. The men were starting to laugh at her now. Musa did an impersonation of her swaying hips, tossing his head grandly: “ ‘Oh, aquarius, come with me!’ ”

She turned, with tears of frustration glinting in her eyes.

“Corelia Ampliata,” said Attilius patiently and not unkindly, “I may not be able to afford to eat red mullet, but I believe them to be seawater fish. And I have no responsibility for the sea.”

Corax grinned and pointed. “Do you hear that? She thinks you’re Neptune!”

There was more laughter. Attilius told them sharply to be quiet.

“My father is putting a man to death. The slave was screaming for the aquarius. That is all I know. You are his only hope. Will you come or not?”

“Wait,” said Attilius. He nodded toward the older woman, who had her hands pressed to her face and was crying, her head bowed. “Who is this?”

“She’s his mother.”

The men were quiet now.

“Do you see?” Corelia reached out and touched his arm. “Come,” she said quietly. “Please.”

“Does your father know where you are?”

“No.”

“Don’t interfere,” said Corax. “That’s my advice.”

And wise advice,thought Attilius, for if a man were to take a hand every time he heard of a slave being cruelly treated, he would have no time to eat or sleep. A seawater pool full of dead mullet? That was nothing to do with him. He looked at Corelia. But then again, if the poor wretch was actuallyasking for him . . .

Omens, portents, auspices.

Vapor that jerked like a fishing line. Springs that ran backward into the earth. An aquarius who vanished into the hot air. On the pastured lower slopes of Mount Vesuvius, shepherds had reported seeing giants. In Herculaneum, according to the men, a woman had given birth to a baby with fins instead of feet. And now an entire pool of red mullet had died in Misenum, in the space of a single afternoon, of no apparent cause.

A man must make such sense of it as he could.

He scratched his ear. “How far away is this villa?”

“Please. A few hundred paces. No distance at all.” She tugged at his arm, and he allowed himself to be pulled along. She was not an easy woman to resist, this Corelia Ampliata. Perhaps he ought at least to walk her back to her family? It was hardly safe for a woman of her age and class to be out in the streets of a naval town. He shouted over his shoulder to Corax to follow, but Corax shrugged—“Don’t interfere!” he repeated—and then Attilius, almost before he realized what was happening, was out of the gate and into the street, and the others were lost from sight.

It was that time of day, an hour or so before dusk, when the people of the Mediterranean begin emerging from their houses. Not that the town had lost much of its heat. The stones were like bricks from a kiln. Old women sat on stools beside their porches, fanning themselves, while the men stood at the bars, drinking and talking. Thickly bearded Bessians and Dalmatians, Egyptians with gold rings in their ears, redheaded Germans, olive-skinned Greeks and Cilicians, great muscled Nubians as black as charcoal and with eyes bloodshot by wine—men from every country of the empire, all of them desperate enough, or ambitious enough, or stupid enough, to be willing to trade twenty-five years of their lives at the oars in return for Roman citizenship. From somewhere down in the town, near the harbor front, came the piping notes of a water organ.

Corelia was mounting the steps quickly, her skirts gathered up in either hand, her slippers soft and soundless on the stone, the slave woman running on ahead. Attilius loped behind them. “ ‘A few hundred paces,’ ” he muttered to himself, “ ‘no distance at all’—yes, but every foot of the way uphill!” His tunic was glued to his back by his sweat.

They came at last to level ground and before them was a long high wall, dun-colored, with an arched gate set into it, surmounted by two wrought-iron dolphins leaping to exchange a kiss. The women hurried through the unguarded entrance, and Attilius, after a glance around, followed—plunging at once from noisy, dusty reality into a silent world of blue that knocked away his breath. Turquoise, lapis lazuli, indigo, sapphire—every jeweled blue that Mother Nature had ever bestowed—rose in layers before him, from crystal shallows, to deep water, to sharp horizon, to sky. The villa itself sprawled below on a series of terraces, its back to the hillside, its face to the bay, built solely for this sublime panorama. Moored to a jetty was a twenty-oared luxury cruiser, painted crimson and gold, with a carpeted deck to match.

He had little time to register much else, apart from this engulfing blueness, before they were off again, Corelia in front now, leading him down, past statues, fountains, watered lawns, across a mosaic floor inlaid with a design of sea creatures and out onto a terrace with a swimming pool, also blue, framed in marble, projecting toward the sea. An inflatable ball turned gently against the tiled surround, as if abandoned in midgame. He was suddenly struck by how deserted the great house seemed and when Corelia gestured to the balustrade, and he laid his hands cautiously on the stone parapet and leaned over, he saw why. Most of the household was gathered along the seashore.

It took a while for his mind to assemble all the elements of the scene. The setting was a fishery, as he had expected, but much bigger than he had imagined—and old, by the look of it, presumably built in the decadent last years of the republic, when keeping fish had first become the fashion—a series of concrete walls, extending out from the rocks, enclosing rectangular pools. Dead fish dappled the surface of one. Around the most distant, a group of men was staring at something in the water, an object that one of them was prodding with a boat hook—Attilius had to shield his eyes to make them out—and as he studied them more closely he felt his stomach hollow. It reminded him of the moment of the kill at the amphitheater—the stillness of it, the erotic complicity between crowd and victim.

Behind him, the old woman started making a noise—a soft ululation of grief and despair. He took a step backward and turned toward Corelia, shaking his head. He wanted to escape from this place. He longed to return to the decent, simple practicalities of his profession. There was nothing he could do here.

But she was in his way, standing very close. “Please,” she said. “Help her.”

Her eyes were blue, bluer even than Sabina’s had been. They seemed to collect the blueness of the bay and fire it back at him. He hesitated, set his jaw, then turned and reluctantly looked out to sea again.

He forced his gaze down from the horizon, deliberately skirting what was happening at the pool, let it travel back toward the shore, tried to appraise the whole thing with a professional eye. He saw wooden sluice gates. Iron handles to raise them. Metal lattices over some of the ponds to keep the fish from escaping. Gangways. Pipes.Pipes.

He paused, then swung around again to squint at the hillside. The rising and falling of the waves would wash through metal grilles, set into the concrete sides of the fish pools, beneath the surface, to prevent the pens becoming stagnant. That much he knew. Butpipes —he cocked his head, beginning to understand—the pipes must carry freshwater down from the land, to mix with the seawater, to make it brackish. As in a lagoon. An artificial lagoon. The perfect conditions for rearing fish. And the most sensitive of fish to rear, a delicacy reserved only for the very rich, were red mullet.

He said quietly, “Where does the aqueduct connect to the house?”

Corelia shook her head. “I don’t know.”

It would have to be big,he thought.A place this size . . .

He knelt beside the swimming pool, scooped up a palmful of the warm water, tasted it, frowning, swilled it round in his mouth like a connoisseur of wine. It was clean, as far as he could judge. But then again, that might mean nothing. He tried to remember when he had last checked the outflow of the aqueduct. Not since the previous evening, before he went to bed.

“At what time did the fish die?”

Corelia glanced at the slave woman, but she was lost to their world. “I don’t know. Perhaps two hours ago?”

Two hours!

He vaulted over the balustrade onto the lower terrace beneath and started to stride toward the shore.

Down at the water’s edge, the entertainment had not lived up

to its promise. But then nowadays, what did? Ampliatus felt

increasingly that he had reached some point—age, was it, or wealth?—when the arousal of anticipation was invariably more exquisite than the emptiness of relief. The voice of the victim cries out, the blood spurts, and then—what? Just another death.

The best part had been the beginning: the slow preparation, followed by the long period when the slave had merely floated, his face just above the surface—very quiet now, not wanting to attract any attention from what was beneath him, concentrating, treading water. Amusing. Even so, time had dragged in the heat, and Ampliatus had started to think that this whole business with eels was overrated and that Vedius Pollio was not quite as stylish as he had imagined. But no: you could always rely on the aristocracy! Just as he was preparing to abandon the proceedings, the water had begun to twitch and then—plop!—the face had disappeared, like a fisherman’s plunging float, only to bob up again for an instant, wearing a look of comical surprise, and then vanish altogether. That expression, in retrospect, had been the climax. After that, it had all become rather boring and uncomfortable to watch in the heat of the sinking afternoon sun.

Ampliatus took off his straw hat, fanned his face, looked around at his son. Celsinus at first appeared to be staring straight ahead, but when you looked again you saw his eyes were closed, which was typical of the boy. He always seemed to be doing what you wanted. But then you realized he was only obeying mechanically, with his body: his attention was elsewhere. Ampliatus gave him a poke in the ribs with his finger and Celsinus’s eyes jerked open.

What was in his mind? Some Eastern rubbish, presumably. He blamed himself. When the boy was six—this was twelve years ago—Ampliatus had built a temple in Pompeii, at his own expense, dedicated to the cult of Isis. As a former slave, he would not have been encouraged to build a temple to Jupiter, Best and Greatest, or to Mother Venus, or to any of the other most sacred guardian deities. But Isis was Egyptian, a goddess suitable for women, hairdressers, actors, perfume-makers, and the like. He had presented the building in Celsinus’s name, with the aim of getting the boy onto Pompeii’s ruling council. And it had worked. What he had not anticipated was that Celsinus would take it seriously. But he did and that was what he would be brooding about now, no doubt—about Osiris, the sun god, husband to Isis, who is slain each evening at sundown by his treacherous brother, Set, the bringer of darkness. And how all men, when they die, are judged by the Ruler of the Kingdom of the Dead, and if found worthy are granted eternal life, to rise again in the morning like Horus, heir of Osiris, the avenging new sun, bringer of light. Did Celsinus really believe all this girlish twaddle? Did he really think that this half-eaten slave, for example, might return from his death at sundown to wreak his revenge at dawn?

Ampliatus was turning to ask him exactly that when he was distracted by a shout from behind him. There was a stir among the assembled slaves and Ampliatus shifted further round in his chair. A man whom he did not recognize was striding down the steps from the villa, waving his arm above his head and calling out.

The principles of engineering were simple, universal, impersonal—in Rome, in Gaul, in Campania—which was what Attilius liked about them. Even as he ran, he was envisaging what he could not see. The mainline of the aqueduct would be up in that hill at the back of the villa, buried a yard beneath the surface, running on an axis north to south, from Baiae down to the Piscina Mirabilis. And whoever had owned the villa when the Aqua Augusta was built, more than a century ago, would almost certainly have run two spurs off it. One would disgorge into a big cistern to feed the house, the swimming pool, the garden fountains: if there was contamination on the matrix, it might take as long as a day for it to work through the system, depending on the size of the tank. But the other spur would channel a share of the Augusta’s water directly down to the fishery to wash through the various ponds: any problem with the aqueduct and the impact there would be immediate.

Ahead of him, the tableau of the kill was beginning to assume an equally clear shape: the master of the household—Ampliatus, presumably—rising in astonishment from his chair, the spectators now with their backs turned to the pool, all eyes on him as he sprinted down the final flight of steps. He ran onto the concrete ramp of the fishery, slowing as he approached Ampliatus but not stopping.

“Pull him out!” he said as he ran past him.

Ampliatus, his thin face livid, shouted something at his back and Attilius turned, still running, trotting backward now, holding up his palms: “Please. Just pull him out.”

Ampliatus’s mouth gaped open, but then, still staring intently at Attilius, he slowly raised his hand—an enigmatic gesture, which nevertheless set off a chain of activity, as though everyone had been waiting for exactly such a signal. The steward of the household put two fingers to his mouth and whistled at the slave with the boat hook, and made an upward motion with his hand, at which the slave swung round and flung the end of his pole toward the surface of the eel pond, hooked something, and began to drag it in.

Attilius was almost at the pipes. Closer to, they were larger than they had looked from the terrace. Terra-cotta. A pair. More than a foot in diameter. They emerged from the slope, traversed the ramp together, parted company at the edge of the water, then ran in opposite directions along the side of the fishery. A crude inspection plate was set into each—a loose piece of pipe, two feet long, cut crossways—and as he reached them he could see that one had been disturbed and not replaced properly. A chisel lay nearby, as if whoever had been using it had been disturbed.

Attilius knelt and jammed the tool into the gap, working it up and down until it had penetrated most of the way, then twisted it, so that the flat edge gave him enough space to fit his fingers underneath the cover and lever it off. He lifted it away and pushed it over, not caring how heavily it fell. His face was directly over the running water and he smelled it at once. Released from the confined space of the pipe, it was strong enough to make him want to retch. An unmistakable smell of rottenness. Of rotten eggs.

The breath of Hades.

Sulfur.

The slave was dead. That much was obvious, even from a distance. Attilius, crouching beside the open pipe, saw the remains hauled out of the eel pond and covered with a sack. He saw the audience disperse and begin traipsing back up to the villa, at the same time as the gray-headed slave woman threaded her way between them, heading in the opposite direction, down toward the sea. The others avoided looking at her, left a space around her, as if she had some virulent disease. As she reached the dead man she flung up her hands to the sky and began rocking silently from side to side. Ampliatus did not notice her. He was walking purposefully toward Attilius. Corelia was behind him and a young man who looked just like her—her brother, presumably—and a few others. A couple of the men had knives at their belts.

The engineer returned his attention to the water. Was it his imagination or was the pressure slackening? The smell was certainly much less obvious now that the surface was open to the air. He plunged his hands into the flow, frowning, trying to gauge the strength of it, as it twisted and flexed beneath his fingers, like a muscle, like a living thing. Once, when he was a boy, he had seen an elephant killed at the Games—hunted down by archers and by spearmen dressed in leopard skins. But what he remembered chiefly was not the hunt but rather the way the elephant’s trainer, who had presumably accompanied the giant beast from Africa, had crouched at its ear as it lay dying in the dust, whispering to it. That was how he felt now. The aqueduct, the immense Aqua Augusta, seemed to be dying in his hands.

A voice said, “You are on my property.”

He looked up to find Ampliatus staring down at him. The villa’s owner was in his middle fifties. Short, but broad-shouldered and powerful. “My property,” Ampliatus repeated.

“Your property, yes. But the emperor’s water.” Attilius stood, wiping his hands on his tunic. The waste of so much precious liquid, in the middle of a drought, to pamper a rich man’s fish, made him angry. “You need to close the sluices to the aqueduct. There’s sulfur in the matrix and red mullet abominate all impurities.That ”—he emphasized the word—“is what killed your precious fish.”

Ampliatus tilted his head back slightly, sniffing the insult. He had a fine, rather handsome face. His eyes were the same shade of blue as his daughter’s. “And you are who, exactly?”

“Marcus Attilius. Aquarius of the Aqua Augusta.”

“Attilius?” The millionaire frowned. “What happened to Exomnius?”

“I wish I knew.”

“But surely Exomnius is still the aquarius?”

“No. As I said, I am now the aquarius.” The engineer was in no mood to pay his respects. Contemptible, stupid, cruel—on another occasion, perhaps, he would be delighted to pass on his compliments, but for now he did not have the time. “I must get back to Misenum. We have an emergency on the aqueduct.”

“What sort of emergency? Is it an omen?”

“You could say that.”

He made to go, but Ampliatus moved swiftly to one side, blocking his way. “You insult me,” he said. “On my property. In front of my family. And now you try to leave without offering any apology?” He brought his face so close to Attilius’s that the engineer could see the sweat beading above his thinning hairline. He smelled sweetly of crocus oil, the most expensive unguent. “Who gave you permission to come here?”

“If I have in any way offended you—” began Attilius. But then he remembered the wretched bundle in its shroud of sacking and the apology choked in his throat. “Get out of my way.”

He tried to push his way past, but Ampliatus grabbed his arm and someone drew a knife. Another instant, he realized—a single thrust—and it would all be over.

“He came because of me, father. I invited him.”

“What?”

Ampliatus wheeled around on Corelia. What he might have done, whether he would have struck her, Attilius would never know, for at that instant a terrible screaming started. Advancing along the ramp came the gray-headed woman. She had smeared her face, her arms, her dress, with her son’s blood and her hand was pointing straight ahead, the first and last of her bony brown fingers rigidly extended. She was shouting in a language Attilius did not understand. But then he did not need to: a curse is a curse in any tongue, and this one was directed straight at Ampliatus.

He let go of Attilius’s arm and turned to face her, absorbing the full force of it, with an expression of indifference. And then, as the torrent of words began to slacken, he laughed. There was silence for a moment, then the others began to laugh as well. Attilius glanced at Corelia, who gave an almost imperceptible nod and gestured with her eyes to the villa—I shall be all right,she seemed to be saying,go —and that was the last that he saw or heard, as he turned his back on the scene and started mounting the path up to the house, two steps, three steps at a time, running on legs of lead, like a man escaping in a dream.

HORA DUODECIMA

[18:48 hours]

Immediately before an eruption, there may be a marked increase

in the ratios S/C, SO₂/CO₂, S/Cl, as well as the total amount of

HCl. . . . A marked increase in the proportions of mantle

components is often a sign that magma has risen into a

dormant volcano and that an eruption may be expected.

—VOLCANOLOGY(SECOND EDITION)

An aqueduct was a work of man, but it obeyed the laws of nature. The engineers might trap a spring and divert it from its intended course, but once it had begun to flow, it ran, ineluctable, remorseless, at an average speed of two and a half miles per hour, and Attilius was powerless to prevent it polluting Misenum’s water.

He still carried one faint hope: that somehow the sulfur was confined to the Villa Hortensia; that the leak was in the pipework beneath the house; and that Ampliatus’s property was merely an isolated pocket of foulness on the beautiful curve of the bay.

That hope lasted for as long as it took him to sprint down the hill to the Piscina Mirabilis, to roust Corax from the barracks where he was playing a game of bones with Musa and Becco, to explain what had happened, and to wait impatiently while the overseer unlocked the door to the reservoir—at which moment it evaporated completely, wafted away by the same rank smell that he had detected in the pipe at the fishery.

“Dog’s breath!” Corax blew out his cheeks in disgust. “This must have been building up for hours.”

“Two hours.”

“Two hours?” The overseer could not quite disguise his satisfaction. “When you had us up in the hills on your fool’s errand?”

“And if we had been here? What difference could we have made?”

Attilius descended a couple of the steps, the back of his hand pressed to his nose. The light was fading. Out of sight, beyond the pillars, he could hear the aqueduct disgorging into the reservoir, but with nothing like its normal percussive force. It was as he had suspected at the fishery: the pressure was dropping, fast.

He called up to the Greek slave, Polites, who was waiting at the top of the steps, that he wanted a few things fetched—a torch, plans of the aqueduct’s mainline, and one of the stoppered bottles from the storeroom, which they used for taking water samples. Polites trotted off obediently and Attilius peered into the gloom, glad that the overseer could not see his expression, for a man was his face; the face the man.

“How long have you worked on the Augusta, Corax?”

“Twenty years.”

“Anything like this ever happen before?”

“Never. You’ve brought us all bad luck.”

Keeping one hand on the wall, Attilius made his way cautiously down the remaining steps to the reservoir’s edge. The splash of water falling from the mouth of the Augusta, together with the smell and the melancholy light of the day’s last hour, made him feel as if he were descending into hell. There was even a rowboat moored at his feet: a suitable ferry to carry him across the Styx.

He tried to make a joke of it, to disguise the panic that was fastening hold of him. “You can be my Charon,” he said to Corax, “but I don’t have a coin to pay you.”

“Well, then—you are doomed to wander in hell forever.”

That was funny. Attilius tapped his fist against his chest, his habit when thinking, then shouted back up toward the yard, “Polites! Get a move on!”

“Coming, aquarius!”

The slim outline of the slave appeared in the doorway, holding a taper and a torch. He ran down and handed them to Attilius, who touched the glowing tip to the mass of tow and pitch. It ignited with awumph and a gust of oily heat. Their shadows danced on the concrete walls.

Attilius stepped carefully into the boat, holding the torch aloft, then turned to collect the rolled-up plans and the glass bottle. The boat was light and shallow-bottomed, used for maintenance work in the reservoir, and when Corax climbed aboard it dipped low in the water.

I must fight my panic,thought Attilius.I must be the master.

“If this had happened when Exomnius was here, what would he have done?”

“I don’t know. But I tell you one thing. He knew this water better than any man alive. He would have seen this coming.”

“Perhaps he did, and that was why he ran away.”

“Exomnius was no coward. He didn’t run anywhere.”

“Then where is he, Corax?”

“I’ve told you, pretty boy, a hundred times: I don’t know.”

The overseer leaned across, untied the rope from its mooring ring, and pushed them away from the steps, then turned to sit facing Attilius and took up the oars. His face in the torchlight was swarthy, guileful, older than his forty years. He had a wife and a brood of children crammed into an apartment across the street from the reservoir. Attilius wondered why Corax hated him so much. Was it simply that he had coveted the post of aquarius for himself and resented the arrival of a younger man from Rome? Or was there something more?

He told Corax to row them toward the center of the piscina and when they reached it he handed him the torch, uncorked the bottle, and rolled up the sleeves of his tunic. How often had he seen his father do this, in the subterranean reservoir of the Claudia and the Anio Novus on the Esquiline Hill? The old man had shown him how each of the matrices had its own flavor, as distinct from one another as different vintages of wine. The Aqua Marcia was the sweetest-tasting, drawn from the three clear springs of the River Anio; the Aqua Alsietina the foulest, a gritty lakewater, fit only for irrigating gardens; the Aqua Julia, soft and tepid; and so on. A good aquarius, his father had said, should know more than just the solid laws of architecture and hydraulics—he should have a taste, a nose, a feel for water, and for the rocks and soils through which it had passed on its journey to the surface. Lives might depend on this skill.

An image of his father flashed into his mind. Killed before he was fifty by the lead he had worked with all his life, leaving Attilius, a teenager, as head of the family. There had not been much left of him by the end. Just a thin shroud of white skin stretched taut over sharp bone.

His father would have known what to do.

Holding the bottle so that its top was facedown to the water, Attilius stretched over the side and plunged it in as far as he could, then slowly turned it underwater, letting the air escape in a stream of bubbles. He recorked it and withdrew it.

Settled back in the boat, he opened the bottle again and passed it back and forth beneath his nose. He took a mouthful, gargled, and swallowed. Bitter, but drinkable, just about. He passed it to Corax, who swapped it for the torch and gulped the whole lot down in one go. He wiped his mouth with the back of his hand. “It’ll do,” he said, “if you mix it with enough wine.”

The boat bumped against a pillar and Attilius noticed the widening line between the dry and damp concrete—sharply defined, already a foot above the surface of the reservoir. She was draining away faster than the Augusta could fill her.

Panic again.Fight it.

“What’s the capacity of the piscina?”

“Two hundred and eighty quinariae.”

Attilius raised the torch toward the roof, which disappeared into the shadows about fifteen feet above them. So that meant the water was perhaps thirty-five feet deep, the reservoir two-thirds full. Suppose it now held two hundred quinariae. At Rome, they worked on the basis that one quinaria was roughly the daily requirement of two hundred people. The naval garrison at Misenum was ten thousand strong, plus, say, another ten thousand civilians.

A simple enough calculation.

They had water for two days. Assuming they could ration the flow to perhaps an hour at dawn and another at dusk. And assuming the concentration of sulfur at the bottom of the piscina was as weak as it was at the top. He tried to think. Sulfur in a natural spring was warm, and therefore rose to the surface. But sulfur when it had cooled to the same temperature as the surrounding water—what did that do? Did it disperse? Or float? Or sink?

Attilius glanced toward the northern end of the reservoir, where the Augusta emerged. “We should check the pressure.”

Corax began to row with powerful strokes, steering them expertly around the labyrinth of pillars toward the falling water. Attilius held the torch in one hand and with the other he unrolled the plans, flattening them out across his knees with his forearm.

The whole of the western end of the bay, from Neapolis to Cumae, was sulfurous—he knew that much. Green translucent lumps of sulfur were dug from the mines in the Leucogaei Hills, two miles north of the aqueduct’s mainline. Then there were the hot sulfur springs around Baiae, to which convalescents came from across the empire. There was a pool called Posidian, named after a freedman of Claudius, that was hot enough to cook meat. Even the sea at Baiae occasionally steamed with sulfur, the sick wallowing in its shallows in the hope of relief. It must be somewhere in this smoldering region—where the sibyl had her cave and the burning holes gave access to the underworld—that the Augusta had become polluted.

They had reached the aqueduct’s tunnel. Corax let the boat glide for a moment, then rowed a few deft strokes in the opposite direction, bringing them to halt precisely beside a pillar. Attilius laid aside the plans and raised the torch. It flashed on an emerald sheen of green mold, then lit the giant head of Neptune, carved in stone, from whose mouth the Augusta normally gushed in a jet-black torrent. But even in the time it had taken to row from the steps the flow had dwindled. It was scarcely more than a trickle.

Corax gave a soft whistle. “I never thought I’d live to see the Augusta dry. You were right to be worried, pretty boy.” He looked at Attilius and for the first time there was a flash of fear across his face. “So what stars were you born under, that you’ve brought this down on us?”

The engineer was finding it difficult to breathe. He pressed his hand to his nose again and moved the torch above the surface of the reservoir. The reflection of the light on the still black water suggested a fire in the depths.

It was not possible, he thought. Aqueducts did not just fail—not like this, not in a matter of hours. The matrices were walled with brick, rendered with waterproof cement, and surrounded by a concrete casing a foot and a half thick. The usual problems—structural flaws, leaks, lime deposits that narrowed the channel—all these needed months, even years to develop. It had taken the Claudia a full decade gradually to close down.

He was interrupted by a shout from the slave, Polites: “Aquarius!”

He half turned his head. He could not see the steps for the pillars, which seemed to rise like petrified oaks from some dark and foul-smelling swamp. “What is it?”

“There’s a rider in the yard, aquarius! He has a message that the aqueduct has failed!”

Corax muttered, “We can see that for ourselves, you Greek fool.”

Attilius reached for the plans again. “Which town has he come from?” He expected the slave to shout back Baiae or Cumae. Puteoli at the very worst. Neapolis would be a disaster.

But the reply was like a punch in the stomach: “Nola!”

The messenger was so rimed with dust he looked more ghost than man. And even as he told his story—of how the water had failed in Nola’s reservoir at dawn and of how the failure had been preceded by a sharp smell of sulfur that had started in the middle of the night—a fresh sound of hooves was heard in the road outside and a second horse trotted into the yard.

The rider dismounted smartly and offered a rolled papyrus. A message from the city fathers at Neapolis. The Augusta had gone down there at noon.

Attilius read it carefully, managing to keep his face expressionless. There was quite a crowd in the yard by now. Two horses, a pair of riders, surrounded by the gang of aqueduct workers who had abandoned their evening meal to listen to what was happening. The commotion was beginning to attract the attention of passersby in the street, as well as some of the local shopkeepers. “Hey, waterman!” shouted the owner of the snack bar opposite, “what’s going on?”

It would not take much, thought Attilius—merely the slightest breath of wind—for panic to take hold like a hillside fire. He could feel a fresh spark of it within himself. He called to a couple of slaves to close the gates to the yard and told Polites to see to it that the two messengers were given food and drink. “Musa, Becco—get hold of a cart and start loading it. Quicklime, puteolanum, tools—everything we might need to repair the matrix. As much as a couple of oxen can pull.”

The two men looked at each other. “But we don’t know what the damage is,” objected Musa. “One cartload may not be enough.”

“Then we’ll pick up extra material as we pass through Nola.”

He strode toward the aqueduct’s office, the messenger from Nola at his heels.

“But what am I to tell the aediles?”

The rider was scarcely more than a boy. The hollows of his eyes were the only part of his face not caked with dirt, the soft pink disks emphasizing his fearful look. “The priests want to sacrifice to Neptune. They say the sulfur is a terrible omen.”

“Tell them we are aware of the problem.” Attilius gestured vaguely with the plans. “Tell them we are organizing repairs.”

He ducked through the low entrance into the small cubicle. Exomnius had left the Augusta’s records in chaos. Bills of sale, receipts and invoices, promissory notes, legal stipulations and opinions, engineers’ reports and storeroom inventories, letters from the department of the Curator Aquarum and orders from the naval commander in Misenum—some of them twenty or thirty years old—spilled out of chests, across a table, and over the concrete floor. Attilius swept the table clear with his elbow and unrolled the plans.

Nola!How was this possible? Nola was a big town, thirty miles to the east of Misenum, and nowhere near the sulfur fields. He used his thumb to mark out the distances. With a cart and oxen it would take them the best part of two days merely to reach it. The map showed him as clearly as a painting how the calamity must have spread, the matrix emptying with mathematical precision. He traced it with his finger, his lips moving silently. Two and a half miles per hour! If Nola had gone down at dawn, then Acerrae and Atella would have followed in the middle of the morning. If Neapolis, twelve miles round the coast from Misenum, had lost its supply at noon, then Puteoli’s must have gone at the eighth hour, Cumae’s at the ninth, Baiae’s at the tenth. And now, at last, inevitably, at the twelfth, it was their turn.

Eight towns down. Only Pompeii, a few miles upstream from Nola, so far unaccounted for. But even without it: more than two hundred thousand people without water.

He was aware of the entrance behind him darkening, of Corax coming up and leaning against the door frame, watching him.

He rolled up the map and tucked it under his arm. “Give me the key to the sluices.”

“Why?”

“Isn’t it obvious? I’m going to shut off the reservoir.”

“But that’s the navy’s water. You can’t do that. Not without the authority of the admiral.”

“Then why don’t you get the authority of the admiral? I’m closing those sluices.” For the second time that day, their faces were barely a hand’s breadth apart. “Listen to me, Corax. The Piscina Mirabilis is a strategic reserve. Understand? That’s what it’s there for—to be shut off in an emergency—and every moment we waste arguing we lose more water. Now give me the key, or you’ll answer for it in Rome.”

“Very well. Have it your way, pretty boy.” Without taking his eyes from Attilius’s face, he removed the key from the ring on his belt. “I’ll go and see the admiral all right. I’ll tell him what’s been going on. And then we’ll see who answers for what.”

Attilius grabbed the key and pushed sideways past him, out into the yard. He shouted to the nearest slave, “Close the gates after me, Polites. No one is to be let in without my permission.”

“Yes, aquarius.”

There was still a crowd of curious onlookers in the street but they cleared a path to let him through. He took no notice of their questions. He turned left, then left again, down a steep flight of steps. The water organ was still piping away in the distance. Washing hung above his head, strung between the walls. People turned to stare at him as he jostled them out of his way. A girl prostitute in a saffron dress, ten years old at most, clutched at his arm and wouldn’t let go until he dug into the pouch on his belt and gave her a couple of copper coins. He saw her dart through the crowd and hand them to a fat Cappadocian—her owner, obviously—and as he hurried on he cursed his gullibility.

The building that housed the sluice gate was a small redbrick cube, barely taller than a man. A statue of Egeria, goddess of the water-spring, was set in a niche beside the door. At her feet lay a few stems of withered flowers and some moldy lumps of bread and fruit—offerings left by pregnant women who believed that Egeria, consort of Numa, the Prince of Peace, would ease their delivery when their time came. Another worthless superstition. A waste of food.

He turned the key in the lock and tugged angrily at the heavy wooden door.

He was level now with the floor of the Piscina Mirabilis. Water from the reservoir poured under pressure down a tunnel in the wall, through a bronze grille, swirled in the open conduit at his feet, and then was channeled into three pipes that fanned out and disappeared under the flagstones behind him, carrying the supply down to the port and town of Misenum. The flow was controlled by a sluice gate, set flush with the wall, worked by a wooden handle attached to an iron wheel. It was stiff from lack of use. He had to pound it with the heel of his hand to loosen it, but when he put his back into it, it began to turn. He wound the handle as fast as he could. The gate descended, rattling like a portcullis, gradually choking off the flow of water until at last it ceased altogether, leaving a smell of moist dust.

Only a puddle remained in the stone channel, evaporating so rapidly in the heat he could see it shrinking. He bent down and dabbed his fingers in the wet patch, then touched them to his tongue. No taste of sulfur.

He had done it now, he thought. Deprived the navy of its water, in a drought, without authority, three days into his first command. Men had been stripped of their rank and sent to the treadmills for lesser crimes. It occurred to him that he had been a fool to let Corax be the first to get to the admiral. There was certain to be a court of inquiry. Even now the overseer would be making sure who got the blame.

Locking the door to the sluice chamber, he glanced up and down the busy street. Nobody was paying him any attention. They did not know what was about to happen. He felt himself to be in possession of some immense secret and the knowledge made him furtive. He headed down a narrow alley toward the harbor, keeping close to the wall, eyes on the gutter, avoiding people’s gaze.

The admiral’s villa was on the far side of Misenum and to reach it the engineer had to travel the best part of half a mile—walking, mostly, with occasional panicky bursts of running—across the narrow causeway and over the revolving wooden bridge that separated

the two natural harbors of the naval base.

He had been warned about the admiral before he left Rome. “The commander in chief is Gaius Plinius,” said the Curator Aquarum. “Pliny. You’ll come across him sooner or later. He thinks he knows everything about everything. Perhaps he does. He will need careful stroking. You should take a look at his latest book. TheNatural History . Every known fact about Mother Nature in thirty-seven volumes.”

There was a copy in the public library at the Porticus of Octavia. The engineer had time to read no further than the table of contents.

“The world, its shape, its motion. Eclipses, solar and lunar. Thunderbolts. Music from the stars. Sky portents, recorded instances. Sky-beams, sky-yawning, colors of the sky, sky-flames, sky-wreaths, sudden rings. Eclipses. Showers of stones . . .”

There were other books by Pliny in the library. Six volumes on oratory. Eight on grammar. Twenty volumes on the war in Germany, in which he had commanded a cavalry unit. Thirty volumes on the recent history of the empire, which he had served as procurator in Spain and Belgian Gaul. Attilius wondered how he managed to write so much and rise so high in the imperial administration at the same time. The Curator said, “Because he doesn’t have a wife.” He laughed at his own joke. “And he doesn’t sleep, either. You watch he doesn’t catch you out.”

The sky was red with the setting sun and the large lagoon to his right, where the warships were built and repaired, was deserted for the evening; a few seabirds called mournfully among the reeds. To his left, in the outer harbor, a passenger ferry was approaching through the golden glow, her sails furled, a dozen oars on either side dipping slowly in unison as she steered between the anchored triremes of the imperial fleet. She was too late to be the nightly arrival from Ostia, which meant she was probably a local service. The weight of the passengers crammed on her open deck was pressing her low to the surface.

“Showers of milk, of blood, of flesh, of iron, of wool, of bricks. Portents. The earth at the center of the world. Earthquakes. Chasms. Air-holes. Combined marvels of fire and water: mineral pitch; naptha; regions constantly glowing. Harmonic principle of the world . . .”

He was moving more quickly than the water pipes were emptying and when he passed through the triumphal arch that marked the entrance to the port he could see that the big public fountain at the crossroads was still flowing. Around it was grouped the usual twilight crowd—sailors dousing their befuddled heads, ragged children shrieking and splashing, a line of women and slaves with earthenware pots at their hips and on their shoulders, waiting to collect their water for the night. A marble statue of the Divine Augustus, carefully positioned beside the busy intersection to remind the citizens who was responsible for this blessing, gazed coldly above them, frozen in perpetual youth.

The overloaded ferry had come alongside the quay. Her gangplanks, fore and aft, had been thrown down and the timber was already bowing under the weight of passengers scrambling ashore. Luggage was tossed from hand to hand. A taxi owner, surprised by the speed of the exodus, was running around kicking his bearers to get them on their feet. Attilius called across the street to ask where the ferry was from, and the taxi owner shouted back over his shoulder, “Neapolis, my friend—and before that, Pompeii.”

Pompeii.

Attilius, on the point of moving off, suddenly checked his stride. Odd, he thought. Odd that they had heard no word from Pompeii, the first town on the matrix. He hesitated, swung round, and stepped into the path of the oncoming crowd. “Any of you from Pompeii?” He waved the rolled-up plans of the Augusta to attract attention. “Was anyone in Pompeii this morning?” But nobody took any notice. They were thirsty after the voyage—and of course they would be, he realized, if they had come from Neapolis, where the water had failed at noon. Most passed to either side of him in their eagerness to reach the fountain, all except for one, an elderly holy man, with the conical cap and curved staff of an augur, who was walking slowly, scanning the sky.

“I was in Neapolis this afternoon,” he said when Attilius stopped him, “but this morning I was in Pompeii. Why? Is there something I can do to help you, my son?” His rheumy eyes took on a crafty look, his voice dropped. “No need to be shy. I am practiced in the interpretation of all the usual phenomena—thunderbolts, entrails, bird omens, unnatural manifestations. My rates are reasonable.”

“May I ask, holy father,” said the engineer, “when you left Pompeii?”

“At first light.”

“And were the fountains playing? Was there water?”

So much rested on his answer, Attilius was almost afraid to hear it.

“Yes, there was water.” The augur frowned and raised his staff to the fading light. “But when I arrived in Neapolis the streets were dry and in the baths I smelled sulfur. That is why I decided to return to the ferry and to come on here.” He squinted again at the sky, searching for birds. “Sulfur is a terrible omen.”

“True enough,” agreed Attilius. “But are you certain? And are you sure the water was running?”

“Yes, my son. I’m sure.”

There was a commotion around the fountain and both men turned to look. It was nothing much to start with, just some pushing and shoving, but quickly punches were being thrown. The crowd seemed to contract, to rush in on itself and become denser, and from the center of the melee a large earthenware pot went sailing into the air, turned slowly, and landed on the quayside, smashing into fragments. A woman screamed. Wriggling between the backs at the edge of the mob, a man in a Greek tunic emerged, clutching a waterskin tightly to his chest. Blood was pouring from a gash in his temple. He sprawled, picked himself up, and stumbled forward, disappearing into an alleyway.

And so it starts, thought the engineer. First this fountain, and then the others all around the port, and then the big basin in the forum. And then the public baths, and then the taps in the military school, and in the big villas—nothing emerging from the empty pipes except the clank of shuddering lead and the whistle of rushing air . . .

The distant water organ had become stuck on a note and died with a long moan.

Someone was yelling that the bastard from Neapolis had pushed to the front and stolen the last of the water, and, like a beast with a single brain and impulse, the crowd turned and began to pour down the narrow lane in pursuit. And suddenly, as abruptly as it had begun, the riot was over, leaving behind a scene of smashed and abandoned pots, and a couple of women crouched in the dust, their hands pressed over their heads for protection, close to the edge of the silent fountain.

VESPERA

[20:07 hours]

Earthquakes may occur in swarms at areas of stress concentrations—

such as nearby faults—and in the immediate vicinity of

magma where pressure changes are occurring.

—HARALDUR SIGURDSSON (EDITOR)

ENCYCLOPEDIA OF VOLCANOES

The admiral’s official residence was set high on the hillside overlooking the harbor and by the time Attilius reached it and was conducted onto the terrace it was dusk. All around the bay, in the seaside villas, torches, oil lamps, and braziers were being lit, so that gradually a broken thread of yellow light had begun to emerge, wavering for mile after mile, picking out the curve of the coast, before vanishing in the purple haze toward Capri.

A marine centurion in full uniform of breastplate and crested helmet, with a sword swinging at his belt, was hurrying away as the engineer arrived. The remains of a large meal were being cleared from a stone table beneath a trellised pergola. At first he did not see the admiral, but the instant the slave announced him—“Marcus Attilius Primus, aquarius of the Aqua Augusta!”—a stocky man in his middle fifties at the far end of the terrace turned on his heel and came waddling toward him, trailed by what Attilius assumed were the guests of his abandoned dinner party: four men sweating in togas, at least one of whom, judging by the purple stripe on his formal dress, was a senator. Behind them—obsequious, malevolent, inescapable—came Corax.

Attilius had for some reason imagined that the famous scholar would be thin, but Pliny was fat, his belly protruding sharply, like the ramming post of one of his warships. He was dabbing at his forehead with his napkin.

“Shall I arrest you now, aquarius? I could, you know, that’s already clear enough.” He had a fat man’s voice: a high-pitched wheeze, which became even hoarser as he counted off the charges on his pudgy fingers. “Incompetence to start with—who can doubt that? Negligence—where were you when the sulfur infected the water? Insubordination—on what authority did you shut off our supply? Treason—yes, I could make a charge of treason stick. What about fomenting rebellion in the imperial dockyards? I’ve had to order out a century of marines—fifty to break some heads in the town and try to restore public order, the other fifty to the reservoir, to guard whatever water’s left. Treason—”

He broke off, short of breath. With his puffed-out cheeks, pursed lips, and sparse gray curls plastered down with perspiration, he had the appearance of an elderly, furious cherub, fallen from some painted, peeling ceiling. The youngest of his guests—a pimply lad in his late teens—stepped forward to support his arm, but Pliny shrugged him away. At the back of the group Corax grinned, showing a mouthful of dark teeth. He had been even more effective at spreading poison than Attilius had expected. What a politician. He could probably show the senator a trick or two.

He noticed that a star had come out above Vesuvius. He had never really looked properly at the mountain before, certainly not from this angle. The sky was dark but the mountain was darker, almost black, rising massively above the bay to a pointed summit. And there was the source of the trouble, he thought. Somewhere there, on the mountain. Not on the seaward side, but round to landward, on the northeastern slope.

“Who are you anyway?” Pliny eventually managed to rasp out. “I don’t know you. You’re far too young. What’s happened to the proper aquarius? What was his name?”

“Exomnius,” said Corax.

“Exomnius, precisely. Where’s he? And what does Acilius Aviola think he’s playing at, sending us boys to do men’s work? Well? Speak up! What have you to say for yourself?”

Behind the admiral Vesuvius formed a perfect natural pyramid, with just that little crust of light from the waterfront villas running around its base. In a couple of places the line bulged slightly and those, the engineer guessed, must be towns. He recognized them from the map. The nearer would be Herculaneum; the more distant, Pompeii.

Attilius straightened his back. “I need,” he said, “to borrow a ship.”

He spread out his map on the table in Pliny’s library, weighing down either side with a couple of pieces of magnetite that he took from a display cabinet. An elderly slave shuffled behind the admiral’s back, lighting an elaborate bronze candelabrum. The walls were lined with cedarwood cabinets, packed with rolls of papyri stacked end-on in dusty honeycombs, and even with the doors to the terrace pushed wide open, no breeze came off the sea to dispel the heat. The oily black strands of smoke from the candles rose undisturbed. Attilius could feel the sweat trickling down the sides of his belly, irritating him, like a crawling insect.

“Tell the ladies we shall rejoin them directly,” said the admiral. He turned away from the slave and nodded at the engineer. “All right. Let’s hear it.”

Attilius glanced around at the faces of his audience, intent in the candlelight. He had been told their names before they sat down and he wanted to make sure he remembered them: Pedius Cascus, a senior senator who, he dimly recalled, had been a consul years ago and who owned a big villa along the coast at Herculaneum; Pomponianus, an old army comrade of Pliny, rowed over for dinner from his villa at Stabiae; and Antius, captain of the imperial flagship, theVictoria . The pimply youth was Pliny’s nephew, Gaius Plinius Caecilius Secundus.

He put his finger on the map and they all leaned forward, even Corax.

“This is where I thought originally that the break must be, admiral—here, in the burning fields around Cumae. That would explain the sulfur. But then we learned that the supply had gone down in Nola as well—over here, to the east. That was at dawn. The timing is crucial, because according to a witness who was in Pompeii at first light, the fountains there were still running this morning. As you can see, Pompeii is some distance back up the matrix from Nola, so logically the Augusta should have failed there in the middle of the night. The fact that it didn’t can only mean one thing. The break has to be here”—he circled the spot—“somewhere here, on this five-mile stretch, where she runs close to Vesuvius.”

Pliny frowned at the map. “And the ship? Where does that come in?”

“I believe we have two days’ worth of water left. If we set off overland from Misenum to discover what’s happened it will take us at least that long simply to find where the break has occurred. But if we go by sea to Pompeii—if we travel light and pick up most of what we need in the town—we should be able to start repairs tomorrow.”

In the ensuing silence, the engineer could hear the steady drip of the water clock beside the doors. Some of the gnats whirling around the candles had become encrusted in the wax.

Pliny said, “How many men do you have?”

“Fifty altogether, but most of those are spread out along the length of the matrix, maintaining the settling tanks and the reservoirs in the towns. I have a dozen altogether in Misenum. I’d take half of those with me. Any other labor we need, I’d hire locally in Pompeii.”

“We could let him have a liburnian, admiral,” said Antius. “If he left at first light he could be in Pompeii by the middle of the morning.”

Corax seemed to be panicked by the mere suggestion. “But with respect, this is just more of his moonshine, admiral. I wouldn’t pay much attention to any of this. For a start, I’d like to know how he’s so sure the water’s still running in Pompeii.”

“I met a man on the quayside, admiral, on my way here. An augur. The local ferry had just docked. He told me he was in Pompeii this morning.”

“An augur!” mocked Corax. “Then it’s a pity he didn’t see this whole thing coming! But all right—let’s say he’s telling the truth. Let’s say this is where the break is. I know this part of the matrix better than anyone—five miles long and every foot of her underground. It will take us more than a day just to find out where she’s gone down.”

“That’s not true,” objected Attilius. “With that much water escaping from the matrix, a blind man could find the break.”

“With that much water backed up in the tunnel, how do we get inside it to make the repairs?”

“Listen,” said the engineer. “When we get to Pompeii, we split into three groups.” He had not really thought this through. He was having to make it up as he went along. But he could sense that Antius was with him and the admiral had yet to take his eyes from the map. “The first group goes out to the Augusta—follows the spur from Pompeii to its junction with the matrix and then works westward. I can assure you, finding where the break is will not be a great problem. The second group stays in Pompeii and puts together enough men and materials to carry out the repairs. A third group rides into the mountains, to the springs at Abellinum, with instructions to shut off the Augusta.”

The senator looked up sharply. “Can that be done? In Rome, when an aqueduct has to be closed for repairs, it stays shut down for weeks.”

“According to the drawings, senator, yes—it can be done.” Attilius had only just noticed it himself, but he was inspired now. The whole operation was taking shape in his mind even as he described it. “I have never seen the springs of the Serinus myself, but it appears from this plan that they flow into a basin with two channels. Most of the water comes west, to us. But a smaller channel runs north, to feed Beneventum. If we send all the water north, and let the western channel drain off, we can get inside to repair it. The point is, we don’t have to dam it and build a temporary diversion, which is what we have to do with the aqueducts of Rome, before we can even start on the maintenance. We can work much more quickly.”

The senator transferred his drooping eyes to Corax. “Is this true, overseer?”

“Maybe,” conceded Corax grudgingly. He seemed to sense he was beaten, but he would not give up without a fight. “However, I still maintain he’s talking moonshine, admiral, if he thinks we can get all this done in a day or two. Like I said, I know this stretch. We had problems here nearly twenty years ago, at the time of the great earthquake. Exomnius was the aquarius, new in the job. He’d just arrived from Rome, his first command, and we worked on it together. All right—it didn’t block the matrix completely, I grant you that—but it still took us weeks to render all the cracks in the tunnel.”

“What great earthquake?” Attilius had never heard mention of it.

“Actually, it was seventeen years ago.” Pliny’s nephew piped up for the first time. “The earthquake took place on the nones of February, during the consulship of Regulus and Verginius. Emperor Nero was in Neapolis, performing onstage at the time. Seneca describes the incident. You must have read it, uncle? The relevant passage is inNatural Questions . Book six.”

“Yes, Gaius, thank you,” said the admiral sharply. “I have read it, although obviously I’m obliged for the reference.” He stared at the map and puffed out his cheeks. “I wonder—” he muttered. He shifted round in his chair and shouted at the slave. “Dromo! Bring me my glass of wine. Quickly!”

“Are you ill, uncle?”

“No, no.” Pliny propped his chin on his fists and returned his attention to the map. “So is this what has damaged the Augusta? An earthquake?”

“Then surely we would have felt it?” objected Antius. “That last quake brought down a good part of Pompeii. They’re still rebuilding. Half the town is a building site. We’ve had no reports of anything on that scale.”

“And yet,” continued Pliny, almost to himself, “this is certainly earthquake weather. A flat sea. A sky so breathless the birds can scarcely fly. In normal times we would anticipate a storm. But when Saturn, Jupiter, and Mars are in conjunction with the sun, instead of occurring in the air, the thunder is sometimes unleashed by nature underground. That is the definition of an earthquake, in my opinion—a thunderbolt hurled from the interior of the world.”

The slave had shuffled up beside him, carrying a tray, in the center of which stood a large goblet of clear glass, three-quarters full. Pliny grunted and lifted the wine to the candlelight.

“A Caecuban,” whispered Pomponianus, in awe. “Forty years old and still drinking beautifully.” He ran his tongue round his fat lips. “I wouldn’t mind another glass myself, Pliny.”

“In a moment. Watch.” Pliny waved the wine back and forth in front of them. It was thick and syrupy, the color of honey. Attilius caught the sweet mustiness of its scent as it passed beneath his nose. “And now watch more closely.” He set the glass carefully on the table.

At first, the engineer did not grasp what point he was trying to make, but as he studied the glass more closely he saw that the surface of the wine was vibrating slightly. Tiny ripples radiated out from the center, like the quivering of a plucked string. Pliny picked up the glass and the movement ceased; he replaced it and the motion resumed.

“I noticed it during dinner. I have trained myself to be alert to things in nature, which other men might miss. The shaking is not continuous. See now—the wine is still.”

“That’s really remarkable, Pliny,” said Pomponianus. “I congratulate you. I’m afraid once I have a glass in my hand, I don’t tend to put it down until it’s empty.”

The senator was less impressed. He folded his arms and pushed himself back in the chair, as if he had somehow made himself look a fool by watching a childish trick. “I don’t know what’s significant about that. So the table trembles? It could be anything. The wind—”

“There is no wind.”

“Heavy footsteps somewhere. Or perhaps Pomponianus here was stroking one of the ladies under the table.”

Laughter broke the tension. Only Pliny did not smile. “We know that this world we stand on, which seems to us so still, is in fact revolving eternally, at an indescribable velocity. And it may be that this mass hurtling through space produces a sound of such volume that it is beyond the capacity of our human ears to detect. The stars out there, for example, might be tinkling like wind chimes, if only we could hear them. Could it be that the patterns in this wineglass are the physical expression of that same heavenly harmony?”

“Then why does it stop and start?”

“I have no answer, Cascus. Perhaps at one moment the earth glides silently, and at another it encounters resistance. There is a school that holds that winds are caused by the earth traveling in one direction and the stars in the other. Aquarius—what do you think?”

“I’m an engineer, admiral,” said Attilius tactfully, “not a philosopher.” In his view, they were wasting time. He thought of mentioning the strange behavior of the vapor on the hillside that morning, but decided against it. Tinkling stars! His foot was tapping with impatience. “All I can tell you is that the matrix of an aqueduct is built to withstand the most extreme forces. Where the Augusta runs underground, which is most of the way, she’s six feet high and three feet wide, and she rests on a base of concrete one and a half feet thick, with walls of the same dimensions. Whatever force breached that must have been powerful.”

“More powerful than the force that shakes my wine?” The admiral looked at the senator. “Unless we are not dealing with a phenomenon of nature at all. In which case, what is it? A deliberate act of sabotage, perhaps, to strike at the fleet? But who would dare? We haven’t had a foreign enemy set foot in this part of Italy since Hannibal.”

“And sabotage would hardly explain the presence of sulfur.”

“Sulfur,” said Pomponianus suddenly. “That’s the stuff in thunderbolts, isn’t it? And who throws thunderbolts?” He looked around excitedly. “Jupiter! We should sacrifice a white bull to Jupiter, as a deity of the upper air, and have the haruspices inspect the entrails. They’ll tell us what to do.”

The engineer laughed.

“What’s so funny about that?” demanded Pomponianus. “It’s not so funny as the idea that the world is flying through space—which, if I may say so, Pliny, rather begs the question of why we don’t all fall off.”

“It’s an excellent suggestion, my friend,” said Pliny soothingly. “As admiral, I also happen to be the chief priest of Misenum, and I assure you, if I had a white bull to hand I would kill it on the spot. But for the time being, a more practical solution may be needed.” He sat back in his chair and wiped his napkin across his face, then unfolded and inspected it, as if it might contain some vital clue. “Very well, aquarius. I shall give you your ship.” He turned to the captain. “Antius—which is the fastest liburnian in the fleet?”

“That would be theMinerva, admiral. Torquatus’s ship. Just back from Ravenna.”

“Have her made ready to sail at first light.”

“Yes, admiral.”

“And I want notices posted on every fountain telling the citizens that rationing is now in force. Water will only be allowed to flow twice each day, for one hour exactly, at dawn and dusk.”

Antius winced. “Aren’t you forgetting that tomorrow is a public holiday, admiral? It’s Vulcanalia, if you recall?”

“I’m perfectly aware it’s Vulcanalia.”

And so it is, thought Attilius. In the rush of leaving Rome and fretting about the aqueduct he had completely lost track of the calendar. The twenty-third of August, Vulcan’s day, when live fish were thrown onto bonfires, as a sacrifice, to appease the god of fire.

“But what about the public baths?” persisted Antius.

“Closed until further notice.”

“They won’t like that, admiral.”

“Well, it can’t be helped. We’ve all grown far too soft in any case.” He glanced briefly at Pomponianus. “The empire wasn’t built by men who lazed around in the baths all day. It will do some people good to have a taste of how life used to be. Gaius—draft a letter for me to sign to the aediles of Pompeii, asking them to provide whatever men and materials may be necessary for the repair of the aqueduct. You know the kind of thing. ‘In the name of the Emperor Titus Caesar Vespasianus Augustus, and in accordance with the power vested in me by the Senate and People of Rome, blah blah’—something to make them jump. Corax—it’s clear that you know the terrain around Vesuvius better than anyone else. You should be the one to ride out and locate the fault, while the aquarius assembles the main expedition in Pompeii.”

The overseer’s mouth flapped open in dismay.

“What’s the matter? Do you disagree?”

“No, admiral.” Corax hid his anxiety quickly, but Attilius had noticed it. “I don’t mind looking for the break. Even so, would it not make more sense for one of us to remain at the reservoir to supervise the rationing—”

Pliny cut him off impatiently. “Rationing will be the navy’s responsibility. It’s primarily a question of public order.”

For a moment Corax looked as if he might be on the point of arguing, but then he bowed his head, frowning.

From the terrace came the sound of female voices and a peal of laughter.

He doesn’t want me to go to Pompeii, thought Attilius suddenly. This whole performance tonight—it’s been to keep me away from Pompeii.

A woman’s elaborately coiffed head appeared in the doorway. She must have been about sixty. The pearls at her throat were the largest Attilius had ever seen. She crooked her finger at the senator. “Cascus, darling, how much longer are you planning to keep us waiting?”

“Forgive us, Rectina,” said Pliny. “We’ve almost finished. Does anyone have anything else to add?” He glanced at each of them in turn. “No? In that case, I for one propose to finish my dinner.”

He pushed back his chair and everyone stood. The ballast of his belly made it hard for him to rise. Gaius offered his arm, but the admiral waved him away. He had to rock forward several times and the strain of finally pushing himself up onto his feet left him breathless. With one hand he clutched at the table, with the other he reached for his glass, then stopped, his outstretched fingers hovering in midair.

The wine had resumed its barely perceptible trembling.

He blew out his cheeks. “I think perhaps I shall sacrifice that white bull after all, Pomponianus. And you,” he said to Attilius, “will give me back my water within two days.” He picked up the glass and took a sip. “Or—believe me—we shall all have need of Jupiter’s protection.”

NOCTE INTEMPESTA

[23:22 hours]

Magma movement may also disturb the local water table, and changes

in flow and temperature of groundwater may be detected.

—ENCYCLOPEDIA OF VOLCANOES

Two hours later—sleepless, naked, stretched out on his narrow wooden bed—the engineer lay waiting for the dawn. The familiar, hammering lullaby of the aqueduct had gone and in its place crowded all the tiny noises of the night—the creak of the sentries’ boots in the street outside, the rustle of mice in the rafters, the hacking cough of one of the slaves downstairs in the barracks. He closed his eyes, only to open them again almost immediately. In the panic of the crisis he had managed to forget the sight of the corpse, dragged from the pool of eels, but in the darkness he found himself replaying the whole scene—the concentrated silence at the water’s edge; the body hooked and dragged ashore; the blood; the screams of the woman; the anxious face and the pale white limbs of the girl.

Too exhausted to rest, he swung his bare feet onto the warm floor. A small oil lamp flickered on the nightstand. His uncompleted letter home lay beside it. There was no point now, he thought, in finishing it. Either he would repair the Augusta, in which case his mother and sister would hear from him on his return. Or they would hearof him, when he was shipped back to Rome, in disgrace, to face a court of inquiry—a dishonor to the family name.

He picked up the lamp and took it to the shelf at the foot of the bed, setting it down among the little shrine’s figures that represented the spirits of his ancestors. Kneeling, he reached across and plucked out the effigy of his great-grandfather. Could the old man have been one of the original engineers on the Augusta? It was not impossible. The records of the Curator Aquarum showed that Agrippa had shipped in a workforce of forty thousand, slaves and legionaries, and had built her in eighteen months. That was six years after he built the Aqua Julia in Rome and seven years before he built the Virgo, and his great-grandfather had certainly worked on both of those. It pleased him to imagine that an earlier Attilius might have come south to this sweltering land—might even have sat on this very spot as the slaves dug out the Piscina Mirabilis. He felt his courage strengthening. Men had built the Augusta; men would fix her.He would fix her.

And then his father.

He replaced one figure and took up another, running his thumb tenderly over the smooth head.

Your father was a brave man; make sure you are, too.

He had been a baby when his father had finished the Aqua Claudia, but so often had he been told the story of the day of its dedication—of how, at four months old, he had been passed over the shoulders of the engineers in the great crowd on the Esquiline Hill—that it sometimes seemed to him he could remember it all at first hand: the elderly Claudius, twitching and stammering as he sacrificed to Neptune, and then the water appearing in the channel, as if by magic, at the exact moment that he raised his hands to the sky. But that had had nothing to do with the intervention of the gods, despite the gasps of those present. That was because his father had known the laws of engineering and had opened the sluices at the head of the aqueduct exactly eighteen hours before the ceremony was due to reach its climax, and had ridden back into the city faster than the water could chase him.

He contemplated the piece of clay in his palm.

And you, father? Did you ever come to Misenum? Did you know Exomnius? The aquarii of Rome were always a family—as close as a cohort, you used to say. Was Exomnius one of those engineers on the Esquiline on your day of triumph? Did he swing me in his arms with the rest?

He stared at the figure for a while, then kissed it and put it carefully with the others.

He sat back on his haunches.

First the aquarius disappears and then the water. The more he considered it, the more convinced he was that these must be connected. But how? He glanced around the roughly plastered walls. No clue here, that was for sure. No trace of any man’s character left behind in this plain cell. And yet, according to Corax, Exomnius had run the Augusta for twenty years.

He retrieved the lamp and went out into the passage, shielding the flame with his hand. Drawing back the curtain opposite, he shone the light into the cubicle where Exomnius’s possessions were stored. A couple of wooden chests, a pair of bronze candelabra, a cloak, sandals, a pisspot. It was not much to show for a lifetime. Neither of the chests was locked, he noticed.

He glanced toward the staircase, but the only sound coming from below was snoring. Still holding the lamp, he lifted the lid of the nearest chest and began to rummage through it with his free hand. Clothes—old clothes mostly—that, as he disturbed them, released a strong smell of stale sweat. Two tunics, loincloths, a toga, neatly folded. He closed the lid quietly and raised the other. Not much in this chest, either. A skin-scraper for removing oil in the baths. A jokey figure of Priapus with a vastly extended penis. A clay beaker for throwing dice, with more penises inlaid around its rim. The dice themselves. A few glass jars containing various herbs and unguents. A couple of plates. A small bronze goblet, badly stained.

He rolled the dice as gently as he could in the beaker and threw them. His luck was in. Four sixes—the Venus throw. He tried again and threw another Venus. The third Venus settled it. Loaded dice.

He put away the dice and picked up the goblet. Was it really bronze? Now he examined it more closely, he was not so sure. He weighed it in his hand, turned it over, breathed on it and rubbed the bottom with his thumb. A smear of gold appeared and part of an engraved letterP. He rubbed again, gradually increasing the radius of gleaming metal, until he could make out all the initials.

N. P. N. l. A.

The“l” stood for“libertus” and showed it to be the property of a freed slave.

A slave who had been freed by an owner whose family name began with aP, and who was rich enough, and vulgar enough, to drink his wine from a gold cup.

Her voice was suddenly as clear in his mind as if she had been standing beside him.

“My name is Corelia Ampliata, daughter of Numerius Popidius Ampliatus, owner of the Villa Hortensia . . .”

The moonlight shone on the smooth black stones of the narrow street and silhouetted the lines of the flat roofs. It felt almost as hot as it had been in the late afternoon; the moon as bright as the sun. As he mounted the steps between the shuttered, silent houses, he could picture her darting before him—the movement of her hips beneath the plain white dress.

“A few hundred paces—yes, but every one of them uphill!”

He came again to the level ground and to the high wall of the great villa. A gray cat ran along it and disappeared over the other side. The glinting metal dolphins leaped and kissed above the chained gate. He could hear the sea in the distance, moving against the shore, and the throb of the cicadas in the garden. He rattled the iron bars and pressed his face to the warm metal. The porter’s room was shuttered and barred. There was not a light to be seen.

He was remembering Ampliatus’s reaction when he turned up on the seashore:“What’s happened to Exomnius? But surely Exomnius is still the aquarius?” There had been surprise in his voice and, now he came to think about it, possibly something more: alarm.

“Corelia!” He called her name softly. “Corelia Ampliata!”

No response. And then a whisper in the darkness, so low he almost missed it: “Gone.”

A woman’s voice. It came from somewhere to his left. He stepped back from the gate and peered into the shadows. He could make out nothing except a small mound of rags piled in a drift against the wall. He moved closer and saw that the shreds of cloth were moving slightly. A skinny foot protruded, like a bone. It was the mother of the dead slave. He went down on one knee and cautiously touched the rough fabric of her dress. She shivered, then groaned and muttered something. He withdrew his hand. His fingers were sticky with blood.

“Can you stand?”

“Gone,” she repeated.

He lifted her carefully until she was sitting, propped against the wall. Her swollen head dropped forward and he saw that her matted hair had left a damp mark on the stone. She had been whipped and badly beaten, and thrown out of the household to die.

N. P. N. l. A: Numerius Popidius Numerii libertus Ampliatus. Granted his freedom by the family Popidii. It was a fact of life that there was no crueler master than an ex-slave.

He pressed his fingers lightly to her neck to make sure she was still alive. Then he threaded one arm under the crook of her knees and with the other he grasped her round her shoulders. It cost him no effort to rise. She was mere rags and bones. Somewhere, in the streets close to the harbor, the night watchman was calling the fifth division of the darkness:“Media noctis inclinatio” —midnight.

The engineer straightened his back and set off down the hill as the day of Mars turned into the day of Mercury.

MERCURY

23 August

The day before the eruption

DILUCULUM

[06:00 hours]

Prior toA.D. 79, a reservoir of magma had accumulated beneath

the volcano. It is not possible to say when this magma chamber began

to form, but it had a volume of at least 3.6 cubic kilometres, was

about 3 km below the surface, and was compositionally stratified,

with volatile-rich alkalic magma (55 percent SiO₂and almost

10 per cent K₂O) overlying slightly denser, more mafic magma.

—PETER FRANCIS,VOLCANOES: A PLANETARY PERSPECTIVE

At the top of the great stone lighthouse, hidden beyond the ridge of the southern headland, the slaves were dousing the fires to greet the dawn. It was supposed to be a sacred place. According to Virgil, this was the ground where Misenus, the herald of the Trojans, slain by the sea god Triton, lay buried with his oars and trumpet.

Attilius watched the red glow fade beyond the tree-crested promontory, while in the harbor the outlines of the warships took shape against the pearl-gray sky.

He turned and walked back along the quay to where the others were waiting. He could make out their faces at last—Musa, Becco, Corvinus, Polites—they were becoming as familiar to him as family. No sign yet of Corax.

“Nine brothels!” Musa was saying. “Believe me, if you want to get laid, Pompeii’s the place. Even Becco can give his hand a rest for a change. Hey, aquarius!” he shouted, as Attilius drew closer. “Tell Becco he can get himself laid!”

The dockside stank of shit and gutted fish. Attilius could see a putrid melon and the bloated, whitened carcass of a rat lapping at his feet between the pillars of the wharf. So much for poets! He had a sudden yearning for one of those cold, northern seas he had heard about—the Atlantic, perhaps, or the Germanicum—a land where a deep tide daily swept the sand and rocks; some place healthier than this tepid Roman lake.

He said, “As long as we fix the Augusta, Becco can screw every girl in Italy for all I care.”

“There you go, Becco. Your prick will soon be as long as your nose—”

The ship the admiral had promised was moored before them: theMinerva, named for the goddess of wisdom, with an owl, the symbol of her deity, carved into her prow. A liburnian. Smaller than the big triremes. Built for speed. Her high sternpost reared out behind her, then curled across her low deck like the stinger of a scorpion preparing to strike. She was deserted.

“—Cuculla and Zmyrina. And then there’s this red-haired Jewess, Martha. And a little Greek girl, if you like that kind of thing—her mother’s barely twenty.”

“What use is a ship without a crew?” muttered Attilius. He was fretting already. He could not afford to waste an hour. “Polites—run to the barracks, there’s a good lad, and find out what’s happening.”

“Aegle and Maria . . .”

The young slave got to his feet.

“No need,” said Corvinus, and gestured with his head toward the entrance to the port. “Here they come.”

Attilius said, “Your ears must be sharper than mine,” but then he heard them, too. A hundred pairs of feet, doubling along the road from the military school. As the marchers crossed the wooden bridge of the causeway, the sharp rhythm became a continuous thunder of leather on wood, then a couple of torches appeared and the unit swung into the street leading to the harbor front. They came on, five abreast, three officers wearing body armor and crested helmets in the lead. At a first shout of command the column halted; at a second, it broke and the sailors moved toward the ship. None spoke. Attilius drew back to let them pass. In their sleeveless tunics, the misshapen shoulders and hugely muscled arms of the oarsmen appeared grotesquely out of proportion to their lower bodies.

“Look at them,” drawled the tallest of the officers. “The cream of the navy: human oxen.” He turned to Attilius and raised his fist in salute. “Torquatus, captain of theMinerva .”

“Marcus Attilius. Engineer. Let’s go.”

It did not take long to load the ship. Attilius had seen no point in dragging the heavy amphorae of quicklime and sacks of puteolanum down from the reservoir and ferrying them across the bay. If Pompeii was, as they decribed her, swarming with builders, he would use the admiral’s letter to commandeer what he needed. Tools, though, were a different matter. A man should always use his own tools.

He arranged a chain to pass them on board, handing each in turn to Musa, who threw them on to Corvinus—axes, sledgehammers, saws, picks and shovels, wooden trays to hold the fresh cement, hoes to mix it, and the heavy flatirons they used to pound it into place—until eventually it had all reached Becco, standing on the deck of theMinerva . They worked swiftly, without exchanging a word, and by the time they had finished it was light and the ship was making ready to sail.

Attilius walked up the gangplank and jumped down to the deck. A line of marines with boat hooks was waiting to push her away from the quay. From his platform beneath the sternpost, next to the helmsman, Torquatus shouted down, “Are you ready, engineer?” and Attilius called back that he was. The sooner they left, the better.

“But Corax isn’t here,” objected Becco.

To hell with him,thought Attilius. It was almost a relief. He would manage the job alone. “That’s Corax’s problem.”

The mooring ropes were cast off. The boat hooks dropped like lances and connected with the dock. Beneath his feet, Attilius felt the deck shake as the oars were unshipped and theMinerva began to move. He looked back toward the shore. A crowd had gathered around the public fountain, waiting for the water to appear. He wondered if he should have stayed at the reservoir long enough to supervise the opening of the sluices. But he had left six slaves behind to run the piscina and the building was ringed by Pliny’s marines.

“There he is!” shouted Becco. “Look! It’s Corax!” He started waving his arms above his head. “Corax! Over here!” He gave Attilius an accusing look. “You see! You should have waited!”

The overseer had been slouching past the fountain, a bag across his shoulder, seemingly deep in thought. But now he looked up, saw them, and started to run. He moved fast for a man in his forties. The gap between the ship and the quay was widening quickly—three feet, four feet—and it seemed to Attilius impossible that he could make it, but when he reached the edge he threw his bag and then leaped after it, and a couple of the marines stretched out and caught his arms and hauled him aboard. He landed upright, close to the stern, glared at Attilius, and jerked his middle finger at him. The engineer turned away.

TheMinerva was swinging out from the harbor, prow first, and sprouting oars, two dozen on either side of her narrow hull. A drum sounded below deck, and the blades dipped. It sounded again and they splashed the surface, two men pulling on each shaft. The ship glided forward—imperceptibly to begin with, but picking up speed as the tempo of the drumbeats quickened. The pilot, leaning out above the ramming post and staring straight ahead, pointed to the right, Torquatus called out an order, and the helmsman swung hard on the huge oar that served as a rudder, steering a course between two anchored triremes. For the first time in four days, Attilius felt a slight breeze on his face.

“You have an audience, engineer!” shouted Torquatus, and gestured toward the hill above the port. Attilius recognized the long white terrace of the admiral’s villa set amid the myrtle groves, and, leaning against the balustrade, the corpulent figure of Pliny himself. He wondered what was going through the old man’s mind. Hesitantly, he raised his arm. A moment later Pliny responded. Then theMinerva passed between the two great warships, theConcordia and theNeptune, and when he looked again the terrace was deserted.