LUIS AGUIRRE had been living in Gibraltar for about a month. He had arrived with the intention of sailing at once upon a vessel bound for Oceanica, where he was to assume his post as a consul to Australia. It was the first important voyage of his diplomatic career. Up to that time he had served in Madrid, in the offices of the Ministry, or in various consulates of southern France, elegant summery places where for half the year life was a continuous holiday. THE SON of a family that had been dedicated to diplomacy by tradition, he enjoyed the protection of influential persons. His parents were dead, but he was helped by his relatives and the prestige of a name that for a century had figured in the archives of the nation. Consul at the age of twenty-five, he was about to set sail with the illusions of a student who goes out into the world for the first time, feeling that all previous trips have been insignificant.