"If I am not Ulysses, I am / his dear, ruthless half brother." So announces Yusef Komunyakaa early in his lush new collection, The Emperor of Water Clocks. And Ulysses (or his half brother) is but one of the characters Komunyakaa conjures over the course of this densely lyrical book. Here his speaker observes a doomed court jester; here another recalls Napoleon as the emperor "tells the doctor to cut out his heart / & send it to the empress, Marie-Louise"; and here he is just a man, reflecting on why he'd "rather die a poet / than a warrior." Through these mutations and migrations and permutations and peregrinations, there are constants: Komunyakaa's jazz-inflected rhythms, his effortlessly surreal images, his celebration of natural beauty and of love. There is also his insistent inquiry into the structures and struggles of power: not only, say, of king against jester but of man against his own desire, and of the present against the pernicious influence of the past. Another brilliant collection from the man David Wojahn has called one of our "most significant and individual voices," The Emperor of Water Clocks delights, challenges, and satisfies.