COMPOSED IN A BURST of inspiration near the end of the poet's life, Rilke's Sonnets to Orpheus represents the consummation of the writer's career, distilling the essence of his poetic wisdom in a gem-like sequence. This new translation-with the original German on facing pages-offers a clear window into the world of this endlessly scintillating cycle of poems. 'Daniel Polikoff's English version of Rilke's last sonnet sequence, perhaps his greatest work, is wholly admirable. Rilke's late work is