A not-too-English charmer, at once sparkling and. pensive, about the tricks that magic plays. ""I wish you were alive,"" says Martha impulsively to the little wooden weather-house couple--who, ascertaining her age, announce that she has nine more wishes. The first, shared with Jonathan from next door, is simple and satisfactory: a short flight. Then, Jonathan and Martha wish for money--practically, in ""50p. pieces, just enough to cover what we want to buy. . . just before we buy whatever it is""--and Martha, to encourage her aspiring-artist-father, secretly buys one of his paintings at the village fair. But she also loses the weather-house inadvertently--and her third wish goes (in an edgy confrontation with a very unpleasant woman) to get it back. Martha and Jonathan become more imaginative. She will be Toby, the family dog, and he will be his pet rabbit, Hercules: an exhilarating but distressing experience for both (aware, now, of how Toby and Hercules really feel)--especially for Martha, who has trouble getting changed back. From that time on, many things go awry. Martha's easygoing family has no special fondness for Jonathan's uptight parents and, in a moment of intense irritation, she tells him so--and is ""stricken to the heart."" If she could only relive those last moments and unsay it! And in ""tricky"" wish number five, the scene is tinglingly replayed. Successive wishes take Martha and Jonathan backward in time (only to witness hardship and ""bewildered incomprehension""), make them invisible (a plus and a minus--plus because they help Martha's brother stand up to a tormentor), and carry them into outer space (the most mundane all-around: a classic nightmare). Then, with one wish left, Jonathan wants to wish for another ten wishes. . . and Martha wants to wish to free the weather-house couple, Mr. and Mrs. Tom, from the enchantment brought on by their own quarrelsome misuse of wishes. A memorable book, delicately calibrated to childhood impulses and apprehensions.