"As one of the country's greatest artists Mary Cassatt has entered the ranks of American heroes," Mathews concludes after 15 years' research. The shortness of the volume (and the plentitude of excellent black-and-white illustrations and color plates) tends to restrict this monograph to survey length. Yet the book includes a clear definition of the artist's personality, a revised chronology, and a balanced analysis of Cassatt's development, showing for example that she was a true Impressionist for only nine years.