Deep in the heart of the French countryside of the Jura lies one of the most curious cultural artefacts in the whole of France: la Saline Royale d'Arc-et-Senans. In I771 the French government appointed the architect Claude-Nicolas Ledoux to oversee the conservation and maintenance of the springs, salt-water wells, and buildings in that place. Seizing his opportunity, Ledoux converted his commission into founding a whole complex that was to serve as a self-supporting community for two hundred workers. After an initial scheme that proved abortive, he conceived a project of ten major buildings, arranged along the perimeter of a semicircle having a diameter of 768 metres. Midway between the heels of this horseshoe, he placed the House of the Director, flanked by buildings containing the salt-wells underground. When it is seen for the first time, the development is overwhelming in its monumentality, and one feels a sense of exhilaration in simply walking across this vast enclosed space. I felt fancifully that this might have been how the French would have constructed one of the larger Oxbridge colleges, had they been given the room and the chance to tackle the job from scratch. The whole area is dominated by and looks towards the Director's building, which is a fine classical edifice framed by a portico of six massive columns and surmounted by a pyramidal pediment. Happily, the Royal Saltworks have survived the ravages of over two hundred years, perhaps because of their remote situation, and as such they constitute one of the outstanding examples of industrial architecture still remaining from the eighteenth century to be found anywhere in Europe. The creator of this enterprise occupies an important niche in French art history; major buildings by Ledoux are to be found in both Paris and various places in the provinces. More pertinent, however, to my present purposes is that, in the best Enlightenment tradition, the Royal Saltworks were underpinned by a central tenet: the belief that human happiness is to be found in the rational exploitation of nature and the healthy organization of labour. Ledoux's own views were set down at length in a work published in I704, entitled LArchitecture consideree sous le rapport de l'art, des mceurs et de la legislation. The title is a manifesto in itself: artistic expression is seen as bound up with customs and the laws: in other words, with the whole socio-political fabric. Whereas the mighty chateau at Versailles had proclaimed the glory of the Sun King, buildings have now come to reflect and enhance the quality of collective public life. I pass from this circular concept to another such, though it was never built: Jeremy Bentham's Panopticon. Bentham's great vision was described in letters he wrote from Russia in 1786, with a couple of postscripts added five years later.2 The