The only sculpture exhibited in his lifetime, Degas's Littler Dancer, Aged Fourteen caused a sensation when it was shown in the Sixth Impressionist Exhibition in 1881. Modeled in colored wax, the sculpture had real human hair tied with ribbon, a cloth bodice and tutu, and silk ballet slippers, and it was enclosed in a glass case like a display in an ethnographic museum. Challenging contemporary ideas about sculpture in its presentation and use of unconventional, lifelike materials, the work was equally startling for its scandalous subject, an adolescent girl on the verge of becoming a woman. Modeled by a minor dancer named Marie van Goethem, who turned fourteen in 1878, the Little Dancer stands in ballet's fourth position, thrusting her chest and chin forward in an unattractive manner at odds with the elegance and glamour usually associated with the ballet. Deeply interested in dance, Degas spent hours attending rehearsals and studying dancers backstage. He drew Marie, both clothed and nude, from several different angles in preparation for the sculpture. After Degas's death his heirs decided to have his wax sculptures cast in bronze and authorized Adrien Hébrard to make an edition of twenty-two casts. This one retains the original skirt supplied by the foundry. Jennifer A. Thompson, from Masterpieces from the Philadelphia Museum of Art: Impressionism and Modern Art (2007), p. 58.