Wagner's Ring is a great masterpiece. But because of the work's rich complexity it is difficult to think sensibly about its text and music. Deryck Cooke, author of The Language of Music and completer of Mahler's Tenth Symphony, displays his masterly common sense in this study of how and why The Ring took the shape it did. It is only a portion of the enormous book he had planned: his untimely death prevented his writing an analysis of the music. But...