I concluded my first Anniversary Address on the summit of a cliff in southern Switzerland: I have since revisited the valley of Poschiavo and contemplated San Romerio from afar, and confirmed the spectacular beauty and historical interest of the site. There, I said, ‘the prehistorian and the medievalist may meet in astonishment and awe’. My aim on this occasion is to draw together a rather different community of interests, not quite so widely spread, but still revealing some width of time and space and scientific interest. A month ago I stood in the heart of old Philadelphia, contemplating the scene of the Declaration of Independence, that charming eighteenth-century hall which reflects in its grace and purity of style the better side of Georgian colonial administration, just as the walking stick of Thomas Jefferson recalls the heroic revolutionaries who created the greatest federal state of the modern world. My wife and I were then led through the heart of that remorseless grid laid by William Penn a century before—the grid from which numberless city plans in the United States were to be copied. And about the centre of the grid we saw the beautiful remnants of the old town, houses and public buildings of the eighteenth and nineteenth centuries, restored and preserved with loving care, and set about, not with twentiethcentury skyscrapers or glass-houses or what-have-you, but with grass, which in the heart of one of the richest cities in the world must be worth innumerable dollars a blade. I saw there the theme for a sermon on town planning as a symbol of many diverse historical, archaeological and humane interests, and for another sermon on the preservation of the heritage.