PETER SACK's books of poetry include In These Mountains, Promised Lands, Natal Command, and the recent Wheel. He is also the author of The English Elegy: Studies in Genre from Spenser to Yeats. Born in South Africa in 1950, he fled his native country during the apartheid era to avoid fighting racial wars in the army. He has said, "I was raised in South Africa. I am now an expatriate, but I am still caught up in that country's history. My work in poetry has usually sought to balance an openness to physical beauty on the one hand against historical suffering on the other." Mr. Sacks teaches literature and creative writing at Harvard University.