BOOK REVIEW / Sevens above: the nightmare explodes: 'Swimming in the Volcano' - Bob Shacochis: Picador, 15.99 pounds

MAKE a dot in the sea; magnify it to a workable size; populate and outfit it. Is there anything more alluring to the world-builder than an island state, a tropical one at that? This one is called St Catherine, and it features beach bars, slums, an aid community, fishermen, government corruption and political rivalry, insanity, a retreat for decadent rock stars, and, of course, the symbolic volcano above it all. The date is 1977, the numerologically ominous year when, in the song of the Jamaican group Culture, the two sevens clashed.

The challenge of imagination lies not in drawing the map - such a scenario is, after all, within the creative range of a computer game designer - but rather in the restraint with which it is manipulated. Its patent instability has to be managed; its

dynamics must be understood in order to prevent it collapsing into chaos, to check the propensity of the novelist and his First World readers to shake their heads and walk away, murmuring: 'The horror]'

As if to check any such misgivings, Bob Shacochis opens with a set-piece that takes him headlong downhill into the narrative on a metaphor for the ability to modulate catastrophe, in this case a car wreck. Mitchell Wilson, a young agricultural economist from the States, is being driven to the airfield by his local friend Isaac Knowles, in one of those First World vehicles that have been turned native by the organic erosion and infiltration of Third World maintenance. The brakes go at the top of the

hill because coconut oil has been substituted for brake fluid: there follows a bravura descent, meticulously punctuated by gear shifts and progressive component failures, interwoven with the more fluent crisis of human emotions.

The car is written off, but both occupants escape with minor injuries. Shacochis has proved that he is a writer of impressive ability and judgement, his approach shaped by a fundamental respect for his subject matter.

The atmosphere always seems too threatening for mockery. At the airfield, slightly impeded by a fire, which spreads to the fire engine itself, Wilson has a rendezvous with a loosely hinged ex-girlfriend who has decided to descend upon him. Johnny isa girl with secrets, mostly narcotics-related. Fatally, she has acquired a husband with some sort of Cuban connection, to the concern of the St Catherine authorities.

The coalition government is split between the corrupt bourgeoisie and the cold young radicals. Enemies are being invented to justify security sweeps. It is Isaac Knowles's misfortune, first, to have been the son of a nationalist martyr and, second,to have hit the car of a minister's wife on the way down the hill, leading him into the embrace of the St Catherine police. The frame for Wilson takes a little longer to prepare. In the end, he is betrayed by the politician in whose idealism he had placed his faith, and whose supporters are paving the roads of the island with good intentions.

The resemblance to Grenada is acknowledged. In one sense, we know the story already. But its power lies mainly in Shacochis's fervently committed writing, always pushing its limits, always wresting more colour and contrast from its imagery. This is a novel that lives up to its ambitions and operates on a heroic scale.

Its touch falters here and there. Shacochis is at liberty to invent a West Indian dialect for the island, but he has a rotten ear for the decadent English rock stars who get a cameo in one drug-sodden scene. There is also a structural limitation: the point of view is that of the white observer who, however distressed, is always a transient.

But it would be pretty remarkable not to come across the odd dud passage in 500 pages, particularly given the writer's need to co-ordinate a large and varied menagerie of characters. And the criterion for judging writing like this is not what vantage point is available to the author, but what he does with his position. In that light, the least credible thing about Swimming in the Volcano is that it is Bob Shacochis's first novel.