So HERE IT is. Over the years we have had the odd radio show and the odd essay, but finally, two decades after he agreed to write it, Christopher Ricks's study of the lyrics of Bob Dylan is bound between hard covers. It is two inches thick, like the books on Dylan by Clinton Heylin, Michael Gray and Dylan himself: another big book on the bard they call His Bobness. 

Ricks's book, of course, is more than just physically big. Dylan's Visions of Sin has the rolling expansiveness of 'Tangled Up in Blue', and like that song it is forever coiling in on itself. Ricks has taken in more about Dylan for this book than might be thought sane, but