This acknowledgment is necessary if I am to say thanks to some experts
to whom I am indebted. There is Captain Charles Benjamin, who read over
the aviation parts of this book with pursed lips and a belligerent
attitude toward questionable statements of fact or observation. There is
Dr. John Drury Clark, whose authoritative knowledge of rocket fuels was
the basis for admitted but not extravagant extrapolation on my part.
There is the crew of a four-engined transport ship, who argued over my
manuscript and settled the argument by a zestful, full-scale
crash-landing drill--repeat, "drill"--expressly to make sure I had
described all the procedure just right. There is Willy Ley, whom I would
like to exempt from responsibility for any statement in the book, while
I acknowledge the value of personal talks with him and the pleasure
anybody who has ever read his books will recognize. And there is Dr.
Hugh S. Rice of the Hayden Planetarium, who will probably be surprised
to find that I feel I owe him gratitude. They are in great part
responsible for the factual matter in this book.