Vesalius’s consilium to Ingrassia, dated Madrid, 1562, in which he clearly described the operation for empyema (pp. 92-98). Although treatment of empyema by surgery was referred to in classical times, it became unfashionable, and Vesalius seems to have been the first to revive the actual use of surgery for this illness. English translation in O’Malley, Andreas Vesalius of Brussels, Berkeley, Univ. of California Press, 1965, pp.398-402.