Published in installments across several decades, Mackey's two epic series--one called Mu, the other Song of the Andoumboulou--bring the attitudes of free jazz and the reverberating patterns of West African ensemble music to the goals of the American encyclopedic long poem á la Charles Olson. The mysterious, even hermetic, new verse extends both of Mackey's epics, even (as his prose foreword explains) merging them, so that they form one enormous...