Vesalius's method of articulating the skeleton and a drawing in the collection of the Wellcome Library.

I am indebted to Dr Robert R Coleman of The Medieval Institute, University of Notre Dame, for his kind assistance with the Biblioteca Ambrosiana drawings collection, to Dr Kliment P Gatzinsky of the Department of Anatomy, Gothenburg University, Sweden, for his consideration of the anatomical content of the paper, and to Mr William Schupbach, curator of the Iconographic Collections of the Wellcome Library, for his comments. I am also grateful to Dr Antonio Clericuzio of the Dipartimento di Scienza e Societa, Universita di Cassino, and to Dr Jeffrey Spier, Dr Florian Harb and Mr Richard Reed, for their assistance and comments.