THE FRUIT PALACE by Charles Nicholl (St. Martin’s: $16.95; 307 pp.)

Cocaine, said the comedian who knew whereof he spoke, is God’s way of telling you that you have too much money.

“The Fruit Palace,” Englishman John Nicholl’s breezy evocation of the Colombian drug trade, had its genesis in a London meeting with his trendy, nose-to-the-wind publisher, who told him over an expensive lunch that countless readers were panting “to know ‘the who, the how and the why’ of the cocaine racket. I could tell him the ‘why’ without going to Colombia at all,” the author recalled. “The ‘why’ is money.”

Early on, Nicholl addresses the fundamental question about cocaine: “Why is it so phenomenally expensive? There are two obvious answers. First, because it is illegal. It is not the coke that costs, but the high risks of supplying it. . . . The second answer is the old economic adage: It costs that much because people will pay that much. . . . In a sense, people like it expensive. The price is all part of its ritzy mystique. On the grace and money circuits, a vial of white snuff is visible kudos. It used to be chopped up with razor blades, but now it’s all credit cards.”

Do we really need another book about the cocaine trade? Nicholl wonders along with us: “Had I really come all this way to write a story about cocaine? Not the plight of the Indians, the politics of underdevelopment, the ruination of the forests, or a dozen other worthy topics, but cocaine. Greed and folly in a handful of snow. A cheap, one-eyed glimpse up the skirts of South America.”

Nicholl decides to charge into the breach. “The Fruit Palace,” the result, is equal parts travelogue, documentary and drugged-out, madcap caper--the latter most reminiscent of “Romancing the Stone.” At its best, the travel writing is lyrical and the Innocent Abroad adventure is not without a certain aimless charm.

But the discursive sections, detailing the economics and chemistry of turning Andean coca leaf into powdered platinum, are intrusive and occasionally so pedestrian that the author himself admits that he is treading water. On Page 202, he observes hopefully, “At last I was going to get this story off the ground.” Another annoying distraction: Nicholl has a snide way of describing characters he meets, particularly non-Anglo-Saxons, in crudely and disparagingly racial and ethnic terms.

Then there is the matter of Fleet Street journalistic ethics, which is to say, none at all. In a bar, misleading a source, he muses, “All this lying for a few jottings on a paper napkin . . . how low could I get? The answer, had I but known it, was plenty lower. . . . The muffled cries of my conscience, gagged and bound in some cerebral cupboard, grew louder.”

What distinguishes this entertaining, quasi-factual version of “Adventures in the Snow Trade” from the dozens which have preceded it, is timing. Local, state and federal law enforcement officials inform us that the cocaine trade route is shifting from south Florida to Southern California, so we might as well get ready for the change in our lives.

Nicholl rehearses the drug’s corrosive effect, not only on the body of the user, but on the body politic of the societies in which it flourishes.

As a result of the “offloading of narco-dollars,” one of Nicholl’s friends observes, Colombia “has got snow in the blood.” The author then touches on the effect large-scale cocaine traffic has had in exporting--in addition to the narco-dollars--Colombia’s “La Violencia” to suburban, middle-class neighborhoods of the Sunbelt. The cocaine trade helped turn Miami’s metropolitan Dade County, already a refuge for right-wing gangsters and flesh-and-drug peddlers no longer welcome in their own countries, into North America’s first Banana Republic. Between the resulting “hecklers’ veto” and “dynamite democracy,” one recently elected official frankly suggested that police could no longer guarantee the safety of those expressing political opinions to the left of Somoza.

Nicholl recalls one particular battle some years ago among the cocaine cowboys, this one Colombians versus their Cuban exile competitors, a running exchange of automatic weapons fire between vehicles on the interstate which ended in a fashionable south Miami shopping mall called Dadeland. After the Wild West shoot-out, they called it “Deadland.”