Our book today is Robert Harris’ drum-tight 2003 historical novel Pompeii, written in the formidable shadow not of Mount Vesuvius but of Edward Bulwer-Lytton’s 1834 corker The Last Days of Pompeii. Bulwer-Lytton’s book has famously lodged in reading history as perhaps the single worst novel ever written (an unjust claim – the title clearly belongs to Catherine Schine’s The Love Letter), and the faint whiff of bathos has clung to the whole subject every since. Vesuvius erupted during the reign of the Roman emperor Titus, throwing enormous amounts of ash into the atmosphere and sending bolt-fast sheets of pyroclastic flow coursing down the slopes of the mountain to bury everything between the peak and the Bay of Naples. The popular seaside town of Pompeii was entombed in an afternoon and lay frozen and unchanging for two thousand years while the grass grew and the seasons changed far above it. Only in the modern era did excavations begin to uncover its quietly stunning secrets – right down to the graffiti on the whorehouse walls.

As a backdrop to fictional drama, it couldn’t get much more tempting. We know the inside floor plans of dozens of specific buildings; we know the names of just the kind of non-emperor everyday folk who so often go unrecorded, and although dozens of haunting body-casings have been discovered, they don’t bear any identification – so a novelist gets the best of both worlds: he can take advantage of his readers’ knowledge of the coming disaster to ratchet up the tension, but he can also contrive to have his characters survive the doom that’s coming their way. Of course, that ready-made dramatic backdrop also makes the whole thing seem extra contrived; writing a Pompeii novel that doesn’t feel artificial is much trickier than it seems.

Harris’ book succeeds completely, and it does that mainly by a process of diversion so subtle and assured that you almost don’t notice it as you’re reading: he switches crises. Dependable, haunted young engineer Attilius has been sent out from Rome to Pompeii not because of Vesuvius, which has been dormant for a very long time; he’s sent out as aquarius because there’s a problem with the great imperial Augusta aqueduct that supplies water to the Roman fleet stationed on the Bay (and commanded by Pliny the Elder, the famous polymath and old salt who would become the only person we know by name who certainly died during the eruption).

Each chapter of Pompeii bears an epigraph taken not from the ancient world but from more or less contemporary geological reference works (I initially thought that was a disastrous decision on Harris’ part, but it’s actually a stroke of genius), so the reader is informed – or reminded – of things Attilius can’t possibly know, including the fact that volcanoes on the brink of major eruptions often rumble and shift the deep-ground all around them in the immediate build-up. The catastrophe of the Augusta’s failure is just a prelude to the much worse catastrophe coming in just a day or two, but Attilius doesn’t know that – readers instead watch him grappling with the immediate problem of water supply, and assessing it with an engineer’s grasp of the inevitable

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 Arella 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.

Harris has done a huge amount of research on volcanoes and the ancient world, and he matches that research with a wondeful ability to put a human face on it all:

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.

Our engineer faces a fractious work-crew under his command, but he also has to deal with imperious local rich landowners who don’t want to face the tough realities he has no choice but to break to them:

Attilius wondered how many of the owners, relaxed and torpid as this sweltering August stretched and yawned and settled itself into is fourth week, would be aware by now of the failure of the aqueduct. Not many, he would guess. Water was something that was carried in by slaves, or which appeared miraculously from the nozzle of one of Sergius Orata’s shower-baths. But they would know soon enough. They would know once they had to start drinking their swimming pools.

Looming over Attilius’ frenzied efforts to fix the Augusta (and, thrown in for good measure, solve the mystery of the disappearance of the previous aquarius), looming over everything and exquisitely employed to do so, is nearing eruption. The reader knows the sheer scope and power of that coming disaster, and Harris beautifully plays on that knowledge, parading plenty of hints in front of Attilius before even his sharp mind begins to guess what’s coming. It’s so well-done you’ll find yourself periodically re-reading the whole thing just for the fun of it (something that’s very unlikely to be true of Harris’ subsequent forays into ancient Roman historical fiction, for instance).

At least, you’ll periodically re-read it until the super-volcano underneath Yosemite blows. But that’s a whole ‘nother novel!