Golf has changed over the years. Balls fly farther. Clubs are made of space-age materials like graphite and titanium. Courses are longer, more demanding, and come in more shapes and sizes with more grass types than ever before. But no one, not ever, dominated the game during any era like Bobby Jones did during his. No one has ever won so much in so short a time. From 1923 when he won his first major, the United States Open, to his retirement in 1930, Jones won the U.S. Amateur five times, the U.S. Open four times, the British Open three times, and the British Amateur once. In 1930, at age twenty-eight, he accomplished what no one else has done when he won the Grand Slam—the U.S. Open, the British Open, the U.S. Amateur, and the British Amateur—in the same year. After...