After nine years investigating the use of hydrogen as a fuel, journalist Hoffmann (McGraw-Hill World News, Bonn) is convinced of its prospective paramount importance. He has interviewed many of the hydrogen advocates and prophets--from the Germans Rudolph Erren and Kurt Well, who were the first to develop many of the ideas for hydrogen-fueled engines in the 1920s and '30s; to the American Roger Billings, who has recently built hydrogen-fueled autos, trucks, and homes; and the Italian Cesare Marchetti, who envisions a ""world authority"" generating energy and distributing it via hydrogen fuel. Hoffmann emphasizes the use of fuels as forms of stored energy--that can be produced under optimum conditions unhampered by the time and location of its final use. He describes the advantages of a hydrogen-fueled economy over one based on fossil fuels: diminished air pollution, and--in the case of hydrogen--essentially infinite supply were it to be electrolytically produced (using solar and nuclear energy). Attractive offshoots of the large-scale production of hydrogen-as-fuel will be the increased use of hydrogen as a chemical feedstock; as a replacement for petroleum in the production of fertilizers; and as a reagent in the direct reduction of iron ore in the manufacture of steel. Additionally, hydrogen can be used in the bacterial synthesis of high-protein food. So Hoffmann shares the enthusiasm of the hydrogen-fuel proponents. He details their grandest dreams of an ultimate hydrogen-fueled global economy: multinational corporations controlling the production of energy at remote nuclear-power islands in the Pacific, energy that is used to produce hydrogen, which is delivered to consumers throughout the world by barges that dwarf petroleum supertankers. Hoffmann acknowledges that the ""'small is beautiful' fraternity"" will be put off by such technological gigantism--but fails to consider, in his projection, a scenario in which hydrogen fuel is but one of many fuels, each used in a function for which it's most appropriate. Still, the book on the subject at present--and entirely accessible to science-supplement readers.