The scale of two cities: the geographies of Paris and London in the 1720s

This essay considers an early eighteenth-century quarrel about the geographical dimensions of Paris and London. The dispute involved representatives of the Académie Royale des Sciences in Paris and the Royal Society in London. The three participants—Guillaume Delisle (1675–1726), Jean-Jacques Dortous de Mairan (1678–1771) and Peter Davall (?–1763)—were French, the first two resident in Paris, the third an exiled Huguenot based in London. From an initial, relatively trivial, confusion about trigonometrical calculations, this inconclusive debate ultimately embraced several wider questions about the nature of cities in classical antiquity and early eighteenth-century Europe, the changing meaning of urban life on the eve of the industrial age, the relationship between population size and urban space, and the relative economic, political and cultural vitality of Catholic absolutist France and Protestant Hanoverian England. Informed by rival claims promoted by Cartesians and Newtonians in London and Paris, the dispute also reflected a pre-existing tension within the Paris Academy about the remit of established and emerging scientific disciplines, specifically astronomy and geography. Subsequent cartographic representations of these two cities, including the Plan Turgot of Paris in the 1730s and the Rocque map of London in the 1740s, can be re-considered with reference to this now forgotten controversy.