My assignment today, as I understand it, is to say something about the Second International Congress of the History of Science, the only previous one held in the United Kingdom; to mention some of the great historians of science which these islands have produced; and to direct our thoughts for a few moments to the historiography of science, technology and medicine, namely the guiding ideas in the light of which one should attempt to write it. So much has already been said in thanks to the city and the university in which we are now assembled that I could hardly add to it, except to express my personal sense of elation at coming on this occasion to the ‘Athens of the North’ where so many distinguished men have lived in the past, from mediaeval times onwards.