434050 Study of a Seated Nude Woman Wearing a Mask, 1863-66 (charcoal and crayon with stumping on paper) by Eakins, Thomas Cowperthwait (1844-1916); 61.6x47.3 cm; Philadelphia Museum of Art, Pennsylvania, PA, USA; (add.info.: The harsh lighting and bare environment in this image tell us that this study probably was made in an evening life class at the Pennsylvania Academy of the Fine Arts about 1863-66. One of the most famous American drawings of the nineteenth century, it demonstrates the artist\'s ability to suggest volume, weight, and particularity in bold strokes. In this period, models were offered masks to wear if they wished to remain anonymous.); 穢 Philadelphia Museum of Art ; Gift of Mrs. Thomas Eakins and Miss Mary Adeline Williams, 1929; American, out of copyright.