Alma Gluck was one of the most popular sopranos of all time. Born Reba Fiersohn in Romania, she came to the United States as an infant. Her Metropolitan Opera debut as Sophie in Massenet's Werther launched her into a high-flying seven-year opera career, but later in life she devoted herself to concerts and recordings. She recorded for Victor, and her vintage 1915 recordings of songs such as Listen to the Mocking Bird and Carry Me Back to Old Virginny sold millions of copies. So plentiful in supply, even in year 2001, are copies of Gluck's records that many 78 collectors regard...