My thanks, foremost and wholeheartedly, go to Mark Lucas. In addition, I am very grateful for the advice given, with patience and generosity, by: Professor Alec Boksenberg of the Royal Greenwich Observatory, Cambridge, England; George G. Walker, defense attorney, San Francisco; Diane Hovarongkura. I fear that more generosity still will be required when they read this book and discover the number of occasions I have failed to follow their advice. Thanks also to the following people who helped or supported me in many different ways while I was writing this book: Kevin Jackson; Rosie Cheetham; Susan Lamb; William Grose; Dudley P. Frasier; Kay Rigbey; Adrian and Felicity Cave; Norman Coward; Alan Dressler.