When he was 11 years old, Yehudi Menuhin astonished the world with his debut performance of the Beethoven Violin Concerto. Critics found his playing perfect and marveled at his maturity. Albert Einstein is said to have told him, "Today, Yehudi, you have once again proved to me that there is a God in Heaven." Menuhin went on to become one of the century's great violinists. A person of varied interests, he has, in addition to performing and recording for more than 50 years, established and directed numerous music festivals, founded a school in England for musically gifted children, been politically active, made films and written several books.

None of this, however, is to be the gleaned from his generous new book, "The Compleat Violinist." Menuhin, now 70, has written not an autobiography but a reminiscence and encouragement for young violinists that is wise, witty and graceful. He offers this distillation of what he has learned in the modest hope that it might save colleagues and young musicians some time and trouble. Without doubt it will, and the book will also please music lovers.

In a series of ruminations set against very down-to-earth glimpses of a master violinist at work, Menuhin ranges from the physics of violin playing to specific exercises for violinists, many of which are yoga-based, to the metaphysics of music-making. The human instinct for continuous refinement is, as he says, found in all cultures, in activities as varied as bathing, painting, cooking, making love and, of course, music-making. The key to achieving ever greater refinement, Menuhin believes, is balance, based on the yoga principle of striving for equilibrium in all things.

Menuhin's references to his childhood are amusing and oblique. How, for instance, was he raised? "As a gift from above . . . my parents acted in lieu of the guardian monks of Tibet who rear the Dalai Lama." What, aside from its voice, attracted him to the violin? Unlike the piano, "a bright set of teeth upon a heavy, mechanical body," the violin comes in small sizes, Menuhin writes, "and the child can pick up the violin as easily as he picks up his teddy bear."

We may also learn how to pick up a violin bow: "as lightly as possible -- rather as one might pick up a newborn bird." He tells what he eats on tour -- grains, fruit, yogurt and fish, never alcohol, sugar or desserts -- and about the rigors of touring. On arriving at a hotel, the first thing Menuhin does is to push all the furniture to the side of his room to make space for practicing and exercise, and he moves the bed to face north-south, his preferred position for sleep. His responsibility on a tour is to give performances that are always polished, refined and fresh. To this end he sequesters himself to practice and rest. If a new work or program must be prepared during a tour, he will work almost around the clock, stopping only briefly to eat or sleep. He finds the process, though ascetic, full of "the inexpressible satisfaction of searching for, and testing yourself against, an ideal of perfection."

Possibly the most surprising revelation from this master violinist is that the violin, and not he, is ultimately the master. He also confesses to being unable to fulfil his great childhood desire -- playing improvised gypsy music -- because of his classical training. Menuhin's wide-ranging observations concerning the heritage of the violin; his theory as to why Russian Jews have cornered the production of virtuoso violinists; his advice about nurturing young musicians; and his thoughts about the sources of performance anxiety -- are all fascinating.

Of a life and career in which very little seems to have gone wrong (he once played badly in Milan), Menuhin has just one complaint. When he was a child, he says, life was simple because he had nothing to do but play the violin. As an adult, however, he lives under a "lowering sky," in danger of being consumed by the demands of public and private life, and must face the prospect of steadily diminishing hours and years in which to practice and perfect his art. Between performances in a city where he appears every four or five years, Menuhin contemplates the possibility that "I will not be coming back. Certainly not as a violinist. Perhaps never again." He adds, in a statement typical of his spirit, "Such realizations concentrate the mind."

Do not be put off by the dull, textbookish photographs used to illustrate this work. They are not nearly as appealing as the few line drawings that have been included. For music lovers and aspiring violinists, I cannot think of a better way to spend a summer afternoon than with "The Compleat Violinist."

The reviewer, a violinist, is the author of "The Virus That Ate Cannibals."