RHINECLIFF, NEW YORK – In Jules Verne’s novel The Mysterious Island , published in 1874, Cyrus Harding, the book’s engineer/hero, declares that “water will one day be employed as fuel, that hydrogen and oxygen which constitute it, used singly or together, will furnish an inexhaustible source of heat and light.” Water, Harding announces, would be decomposed “doubtless by electricity” into hydrogen and oxygen.