In this tony album, Degas's paintings, pastels, drawings and sculptures are grouped thematically in six chapterstheater, horses, portraits, pantomime, dancers, batherseach prefaced by a short biographical sketch. This arrangement follows the authors' sometimes vague interpretations; ``Pantomime,'' for example, splices brothel scenes, a woman in her bathtub and shimmering impressionist landscapes. Gordon and Forge, coauthors of Monet and The Last Flowers of Manet , are primarily concerned here with formalist esthetics. They show how Degas's preoccupation with theater and ballet gave him opportunities for thinking about pictures in new ways. Superb color plates make this a book worth owning. It is pleasingly decked out with old photographs, eyewitness impressions of Degas and his studio, and four of Degas's sonnets. BOMC featured dividend selection. (Oct.)