It's not often one gets a chance to stick a ''hard-to-put-down'' label on a new book. And I certainly didn't expect to apply it to a book about the American hostage crisis in Iran. In fact, I didn't want to read The Destined Hour at all. The idea of being wafted back to the embassy with the hostages or to their homes with their anxious families seemed most unappealing. But as soon as I had leafed through a few pages of this account by former hostage Barry Rosen and his wife, Barbara, I was hooked. (Their coauthor is George Feifer, and the book is published by Doubleday & Co. in New York, 328 pp. $17.95.)
I don't quite know how the writers managed it, though I'm sure it had a lot to do with the book's masterly narrative flow. For pages at a time I forgot that I already knew what was going to happen next. Inevitably it was Barry's account that explains my ragged fingernails, but Barbara's proved to be a surprise bonus. Her courage catapulted this shy woman, who didn't even like to dine alone in a restaurant, into the role of a crusader able to talk with world leaders.
If reading this account is not the depressing experience I expected, Barry's concern for people is partly responsible. From the very beginning he makes his love for the Iranian people clear and understandable. Here he is, talking about them before the embassy was taken:
''I loved their respect for the little courtesies and symbols that enriched daily life. The onion seller, in his little round cap and balloon trousers, took his lunch break in my deadend street. Spreading a tattered blanket directly on the street, he would set out his bread, onions, and yogurt. But he never failed to first place a rose in a chipped glass of water and stand it in the middle of the blanket.''
Then there is his friend, Farhad, typically Iranian in his need to impart affection:
''Farhad made me feel as if I were terribly important to him: that my comfort and happiness were the most interesting and significant matters he would encounter all day. . . . We didn't so much talk as draw closer together.''
But I don't want to falsify this book - it is far removed from saccharine sweetness and light (though light is there). Mr. Rosen makes it clear that most of the captors were bullies, that the hostages' ordeal was very terrible, and that Rosen himself suffered from a frightening illness. We aren't sheltered from the experience, but neither are we asked to share it. It's sympathy not empathy that is evoked.
However, there is a grievance that the Rosens do want the public to share, since they feel we are all affected by it: They maintain that the news media failed - that Americans were not alerted to the evils of the Shah's regime, not told why so many Iranians supported the revolution. The Rosens complain that the emotions of hostage families were milked for the sake of melodrama - even, Barbara feels, when the reports imperilled the safety of the captives. (The Public Broadcasting System, the British Broadcasting Corporation, and The Christian Science Monitor were exceptions, she says.)
I can't even promise you a happy ending. In fact, since this is a true story it doesn't have an ending at all. The Rosens are still tidying away loose ends. Barbara must deal with the fact that the pressure of the ordeal forced her to outgrow her old role. Barry must cope with discouragement over his prison-made resolution. He finds that living each day minute by minute takes more than a decision - it is an art to be acquired through practice.
But, of course, he can say, ''I love walking out of the apartment in the morning; I love returning in the evening.''
What the book does - and this explains why I think it deserves the hard-to-put-down accolade - is to give us a sense of pride. So this, we can tell ourselves, is what we humans are capable of.
''We (the hostages) were a full range of types,'' Barry writes, ''from the generous to the nasty. . . . Most people's first instinct was to support and help.''
A determination not to submit was evident from the beginning. There was Charles Jones, for instance, who showed so much spirit that he was not released with the other blacks. When the militant students broke into the communications vault, they found him frantically destroying classified material to prevent it from falling into their hands. They were furious. His response was: ''Step aside, man, I've got a job to finish.'' A galling no-speaking rule was in force, but Jones ''talked incessantly. His gravelly bass boomed through the prison. . . . He never lowered his voice, even when a team of guards descended on him. He intimidated them.''
The hostages learned to share the news they discovered from combing through the old newspapers used to wrap garbage. They hid their messages in toilet rolls or engraved them on soap. And all the time they were encouraging and comforting each other, building up almost a family sense. I think it was that community feeling that made me find Mr. Rosen's description of boarding the homeward-bound plane so moving:
''Everyone was there. I hugged Bob Ode, whom I hadn't seen since February, and we both started talking at once. A much thinner Dave Roeder grabbed me as hard as I grabbed him. . . . Everyone loved everyone else; everyone's joy was for all the others.''
It was an emotion for the whole country to share and now for readers of this book to experience again. I find John Fowles' Mantissa (Boston: Little, Brown & Co. 196 pp. $13.95) unpleasant - expertly, even poetically written, but definitely unpleasant. It takes the form of a writer's half-dreaming, half-fantasizing, wholly erotic affair with his anthropomorphic muse. Apparently his publishers are banking on its popularity since they are offering a special deluxe edition of for $75. Give me the Rosens' book every time.