A dense, evocative, rewarding journey to the no-man's-land between the realms of music and language. Award-winning music scholar Swain (Colgate Univ.) has written a brave, boundary-breaking book for musical theorists and for those linguists with an excellent music education. Everyone else, however, will have to rely on their gut feelings that a great piece of music has spoken to them or that a poem in a foreign language had music that moved them--two points well explored here. Swain builds an eloquent case for comparing music and spoken language, establishing ``how musical elements are gathered and understood like speech elements; how that understanding is specific to a community of speakers and listeners; how the meaning of music may now broaden and now narrow, ever responsive to its context; how composers can use that context to teach their listeners to hear syntax that endures but for one piece, an ephemeral syntax that is music's answer to metaphor; how composers have imitated linguistic idealists in the production of artificial systems in our century; how music and language have similarly evolved.'' Swain's sentences are not usually this long, but this opening of his eighth and final chapter encapsulates much of the ambitious theorizing that goes on here. Just when we feel the author is stretching a point, he strikes a familiar note with insights such as his observation that we ``are much more forgiving of syntactic errors in the performance of natural language than in music.'' Swain also scores points when comparing the untranslatable quality of musically significant poems to the ``formless, unpredictable blur of sound'' of a foreign musical language. Such high-altitude mountain climbing is not for everyone, but this is a landmark expedition in the exploration of the upper reaches of human communication.