Fire Down Below: A Journey of Exploration from Mexico to Chile.

Fire Down Below.- A Journey of Exploration from Mexico to Chile, by Robert Harvey (Simon & Schuster, 304 pp., $19.95)

IN THIS BOOK'S opening section, on Central America, Robert Harvey seems like a caricature of the eccentric British traveler, modeled more on Basil Seal as played by Peter Sellers than on John Gunther, to whom he is compared in the publisher's blurb. He pulls into Tegucigalpa or wherever in a tearing hurry, peers shuddering into the nearest volcano, chats briefly with a fellow he meets in the bar, then closses down for the night in a mis

erable fleabag of a hotel. Next morning he springs up, makes a five-minute call on the ambassador, hunts down a sinister army officer, whom he shrewdly asks what his men think of Democracy, then bounces over a potholed road to the airport and takes off for the next breathless stop in a flying jalopy that scrapes the tops of the jungle trees on takeoff. Another hectic day is under way! Mr. Harvey takes a dim view of Central America, which he compares with Kampuchea for its callous disregard for human life. (Rather beastly, all that killing, you know.) Fortunately the rest of the book is calmer, and much better. The author knows South America well, having visited its principal countries many times as correspondent for The Economist. He swiftly summarizes the history of each and then deals with the current political and economic situation. His conclusions, in almost every case, are discouraging; Mr. Harvey is no bleeding optimist, though he does close onan upbeat note. The writing in Fire Down Below is uneven. There are some vivid scenes and characters, but too often the author seems simply to have transcribed his rough field notes. But he does get around. He even includes a quick trip to Tierra del Fuego. Curiously, he virtually ignores the drug trade and its gangster jefazos, and since most of the billions of dollars the Latin American countries have been given or loaned were stolen or wasted, he thinks it might be a good idea for them to repudiate their foreign debts entirely.