Untitled 12pp manuscript draft beginning ‘Since the pioneer work of Csapo, beginning about fifteen years ago, it has been realised that from the uterine smooth muscle a protein can be extracted’. Annotated ‘Tokyo 1964’. A version of this lecture was published as ‘Proteins of the contraction mechanism’ in 'Pharmacology of smooth muscle - Proceedings of the 2nd International Pharmacological Meeting, Prague, 20-23 August 1963', 87-94.