Detail showing the sprue remains shaped as rolls of wax preserved on the top and back of the head (see overlay). The artist left these intact on the finished bronze as subtle evidence that the complex sculpture was cast in one piece—an extraordinary feat. Adriaen de Vries (Netherlandish, 1556–1626), Farnese Bull, 1614, H. 103.5 cm (Schlossmuseum, Gotha, Germany, inv. P 50). See Bewer, Francesca G. 2001. “The Sculpture of Adriaen de Vries: A Technical Study.” In Small Bronzes in the Renaissance, edited by Debra Pincus, 158–93. Studies in the History of Art 62. Washington, DC: National Gallery of Art; New Haven, CT: Yale University Press..