BOOK REVIEW / Three bedazzled eyes: 'The Volcano Lover' - Susan Sontag: Cape, 14.99 pounds

IT IS easy to approach The Volcano Lover, Susan Sontag's first novel for 25 years, in a worldly, subtracting spirit. It is a historical novel, and when an original writer flirts with genre the result is often chancy: Vathek and Rasselas are splendid freaks. Successful historical novels might seem less likely to emerge from cool, analytical writers than from hotheads who defy or ignore the risks they are taking - the constant threat of embarrassment, the temptation to over-inform the reader.

Sontag knows all this, and faces it without evasion. In telling the triangular, volcanic love story of Sir William Hamilton, his wife Emma and her lover Nelson, she has chosen, although echoing in her various tones the idiom and flavour of the period, to write from our own time. This gives her a leeway not allowed by a more costumed narrative technique. It also enables the book to support the enormous scale, moral and historical, on which it is set. The elasticity of Sontag's writing carries the melodrama of the plot and the weight of symbol with the grand ease of opera.

In opera, the music can bear up words that are from time to time lame or even silly, not a possibility for a novel. In The Volcano Lover height and control are buoyed up by clear thinking; although it descants, sometimes at essay length, upon abstractions, there is no 'cabinet of curiosities' disjunction between rumination and fiction such as decks so many modern novels in fustian. Sontag embroils the reader in her greater themes through the truth and tact of her depiction of smaller, no less preoccupying events.

The 'domestic' story is dramatic enough. Sir William Hamilton, the volcano lover of the title, is the envoy of the Court of St James to the Kingdom of the Two Sicilies. He has 'the hyperactivity of the heroic depressive', which he soothes by his passion for collecting. Among the things he collects is everything he can possess of the presiding genius of Naples, Mount Vesuvius, which embodies the just-contained violence and rapacity of the city. In doing this, 'he experienced himself as fearless, always an agreeable illusion'. The death of his rich, cultivated and loving wife leaves him more bereft than he could have expected. His nephew, wishing to make an advantageous match, discards his lovely rustic mistress, Emma. In kindness, chastely, Sir William takes her on and teaches her as once he taught his monkey, Jack, who sat puzzling among his Pompeian vases.

Emma's aptitude, her beauty, her now-famous Attitudes (plural in those days, and recorded by Romney and Vigee-Lebrun) come to enrapture Sir William. He makes her his mistress, then his wife. She cares much for him. They enjoy great influence at court. Sir William looks out from his mirrored observatory at a world that is rich and full.

War and Nelson come - though neither Sir William ('The Cavaliere') nor Nelson ('The Hero') is named, in keeping with the operatic resonance of the novel, which is buttressed by references to Tosca. The two men and Emma enter a state of mutual romantic asexual love, brought about by the closeness of death, the glamour of war, and the radiance of great reputation. She is by now actually fat, painted and often drunk, but her style has always been in her excess, and within the folie a trois she is beautiful again. Emma and the one-eyed Hero become lovers. In their three dazzled eyes the raging seas, incessant cannon, and tormented masses of Europe are occluded by great love.

For all the charm of Emma, the urbanity of the Cavaliere, the patriotic fervour of the Hero and the loss the reader feels at their pathetic deaths, it is the tragedy of their bloody context, and their puniness within it, that conclude the book. To convey the acute sadness of things, and still to glorify them, is a high achievement; in this baroque yet urbane novel, Sontag does it with confident subtlety and without sacrifice of wit.