Bob Leszczak, a 30-year veteran of the rock 'n' roll DJ wars, describes his passions as record collecting and music trivia. In Who Did It First? he gets a chance to put those obsessions to good use.

Subtitled "Great Rhythm & Blues Cover Songs & Their Original Artists," Leszczak's book is a listing in alphabetical order of old r&b records, some classics, some that the nation would be better off if they were never heard again, discussed in terms of who originated them and who covered them. For each entry, the author gives the composer, the artist, the label that issued it and its top chart position. Then he offers the same information for the major covers of the recording. For example, "Bo Diddley" was obviously first done by Bo Diddley in 1955 and hit No. 1 on the Billboard R&B chart. Everyone knows that. What most people might not be aware of, however, is that there was a cover version by Joe Reisman & his Orchestra and Chorus (I'll pause for a moment while everyone goes, "Who?") The cover was also issued in 1955 on RCA Records and did not chart at all. Leszczak also points out that another cover of the song was released by Buddy Holly posthumously, which he says was, in contrast to the Reisman version, "rather well done."

So what we have here is a series of mini-histories of a thousand or so songs, many well-remembered, many totally forgotten. Most semi-serious music lovers are aware that Fats Domino had a huge hit in 1957. Most don't know, however, that another New Orleans bluesman, the great Smiley Lewis, did the song in 1954 and did not even hit the charts with it.

In fact, the Domino version had a long tortuous trip to the Billboard No. 5 slot: used in the soundtrack of the 1956 Jayne Mansfield satire of rock 'n' roll The Girl Can't Help It, the song wasn't released as a single until early '57. (Domino also covered another Smiley Lewis cut, "I Hear You Knocking" and did better with it than Lewis.

Who Did It First? is fascinating. It teaches so much that even music fiends don't know and does it in an entertaining manner. Did you know, for instance, that Pat Boone built his career on doing safe, sanitized versions of Little Richard songs? His "Tutti Fruiti" must be a wonder to hear. Were you aware that Wilson Pickett's "Land of a Thousand Dances" was first done by its writer, Chris Kenner, and hit No. 71 on the charts? Before the song got to Pickett, it was also recorded by Thee Midnighters, Cannibal and the Headhunters, and the Soul Creations, among others. Or that Dion's "Ruby Baby," and "Drip Drop" were first done by the Clovers and the Drifters, respectively?

Here's the truth of the matter: don't pick up Who Did It First? if you have an appointment later in the day because you'll be so wrapped up in reading the book that you'll miss your appointment. It's that much fun.

And here's the best part: it's the first volume of a trilogy. Volumes 2 and 3 will cover pop and rock songs, respectively, and I, for one, can't wait.