Transubstantiation is an immense word. Invisible and instantaneous, it is powerful in whatever realm claims it -- ecclesiastic, alchemic, or mythical. Or poetical. It crosses boundaries, and shifts instantaneously this to that. Jerome McGann's book of poems, TRANSUBSTANTIATIONS, is a multitudinous, sometimes hilarious, game-playing, tormented, and deeply provocative collection from decades of his writing. It is the plural of his title, the multiple transubstantiations, that link many of the poems, rattle their territories, and provide both the weight and the lift to this book.