Black mutiny and brigandage stalk the Space-ship Planetara as she speeds to the Moon to pick up a fabulously rich cache of radium-ore. [Illustration: _I stood on the turret-balcony of the Planetara with Dr. Frank, watching the arriving passengers._] _Foreword by Ray Cummings_ I have been thinking that if, during one of those long winter evenings at Valley Forge, someone had placed in George Washington's hands one of our present day best sellers, the illustrious Father of our Country would have read it with considerable emotion. I do not mean what we call a story of science, or fantasy--just a novel of action, adventure and romance. The sort of thing you and I like to read, but do not find amazing in any way at all. But I fancy that George Washington would have found it amazing. Don't you? It might picture, for instance, a factory girl at a sewing machine. George Washington would be amazed at a sewing machine. And the girl, journeying in the subway to and from her work! Stealing an opportunity to telephone her lover at the noon hour; going to the movies in the evening, or listening to a radio. And there might be a climax, perhaps, with the girl and the villain in a transcontinental railway Pullman, and the hero sending frantic telegrams, or telephoning the train, and then chasing it in his airplane. George Washington would have found it amazing! And I am wondering how you and I would feel if someone were to give us now a book of ordinary adventure of the sort which will be published a hundred and fifty years hence. I have been trying to imagine such a book and the nature of its contents. Let us imagine it together. Suppose we walk down Fifth Avenue, a pleasant spring morning of May, 2080. Fifth Avenue, no doubt, will be there. I don't know whether the New York Public Library will be there or not. We'll assume that it is, and that it has some sort of books, printed, or in whatever fashion you care to imagine. The young man library attendant is surprised at our curiously antiquated aspect. We look as though we were dressed for some historical costume ball. We talk old-fashioned English, like actors in an historical play of the 1930 period. But we get the book. The attendant assures us it is a good average story of action and adventure. Nothing remarkable, but he read it himself, and found it interesting. We thank him and take the book. But we find that the language in which it is written is too strange for comfortable reading. And it names so many extraordinary things so casually! As though we knew all about them, which we certainly do not! So we take it to the kind-hearted librarian in the language division. He modifies it to old-fashioned English of 1930, and he puts occasional footnotes to help explain some of the things we might not understand. Why he should bother to do this for us I don't know; but let us assume that he does.