Bafflingly effective, this new collection of poetry from the winner of the 2004 Ruth Lilly Poetry Prize seems too brief and blithe to pack so much wallop. Intense and relaxed, buoyant and rueful, the singular music of Kay Ryan's poetry appeals to a wide audience. Her poems, products of an immaculately off-kilter mind, have appeared everywhere from the Sunday funnies to New York subways to the pages of "The New Yorker" to plaques at the zoo. "The Niagara River," her third collection for the "Grove Press Poetry Series" that began with the publication of "Elephant Rocks," promises to offer similar gems of hidden wonder.