Books about classical music may seem more mainstream than those about the other fine arts. Classical music feels less esoteric, more “accessible” than the other arts--we can enjoy it even while otherwise engaged, something that cannot be done with the plastic or literary arts. No doubt it is for such reasons that mainstream publishers continue to market books about classical music for general consumption.

A good example is “The Rough Guide to Classical Music” (Penguin; $31.99), one of six books on music offered under the rubric of “The Rough Guide” series of travel books. The other titles include The Rough Guide to World Music, The Rough Guide to Jazz, The Rough Guide to Rock, The Rough Guide to Reggae, and The Rough Guide to Opera. It is significant that classical music was chosen first among the fine arts for exploration. The book’s ten writers, whose individual entries are not signed, have listed 194 destinations in the classical musical world, that is to say, have selected 194 composers, listed alphabetically. Beethoven rates about 15 pages of text, Mozart comes next with 13, then Schubert with 12 and Bach with 11. The level of discourse is elementary but not facile: The composers are introduced with a short biographical discussion, followed by highlighted evaluations of their most important works, including at least one recording recommendation on CD. “The Rough Guide to Classical Music” also contains a “basic repertory” of classical music, running to nearly 1,000 works which are listed in the index. The chronology of composers extends from Hildegard von Bingen (1098-1179) to Michael Torke (1961- ).

It is at the extremities of this time line that the “Rough Guide” demonstrates its greatest idiosyncrasies. Of nineteen composers unknown to me, seventeen were of composers working in the 20th century, and eight of these were of Englishmen (Nicholas Maw, Judith Weir, James Macmillan, etc.) Early music figures are sometimes sacrificed if other contemporaries are felt to “cover” the general era: Hence Perotin and Machaut are included, but not Phillipe de Vitry; Antoine Brumel is listed, but neither Busnois nor Binchois.

Of course, no encyclopedia is perfect, and the Penguin group’s tome only disports itself, after all, as a “rough guide.” For the most part it is accurate and conventional in its choices, with articles on the late romantics--Bruckner, Strauss, Sibelius and Prokofiev--being particularly reliable. There are no Canadians.

The world of the string quartet seems less exotic than that of classical music in general (existing in black and white, perhaps, to the latter’s full color), yet this has not deterred one general publisher from offering in paperback, “Indivisible By Four” (Farrar, Straus and Giroux; $22.95), a memoir by Arnold Steinhardt of his thirty-five years as first violinist of the Guarneri Quartet, which holds the record for longevity of association without changes in personnel. It is enjoyable reading--though at an intermediate level in comparison with the beginner’s level of “The Rough Guide.” Readers not familiar with at least half a dozen of the repertoire’s best known works--Beethoven’s third Rasumovsky, for example, or the Ravel and Smetana quartets--may find their attention waning at times. There are interesting discussions of the collective process of text interpretation, meditations on the difficulties of keeping an ensemble together, anecdotes of the group’s adventures “on the road,” and good jokes. Steinhardt, the youngest of the Guarneris, writes with enthusiasm and modesty. Three of the Guarneris are graduates of the Curtis Institute of Music, and like true Philadelphians, they seem equally committed to brotherly love and “democracy” in music making--the book records innumerable votes on artistic matters. As the ensemble’s first violinist--and so its member with the greatest opportunity for independent success--Steinhardt’s sacrifice to the group was perhaps greater than that of his partners. Indeed, by the end of the book the reader begins to feel that the pacific Steinhardt perhaps deserves the lion’s share of credit for the “indivisibility” of his ensemble.