So far, this study has taken in turn the salient components of the system of navigation and its risks. In years of relative equilibrium (1765–74), the seasonal movement left a clear and characteristic presence. The bio-mass of the continent lived in an annual rhythm, producing with the warmth of the sun, the resources of the soil, the benevolence of nature itself. Distance offered linearity of growth on the high seas. Events grew into market turbulence. These elements differentiated insurance for the various lines of ship movements. How can we bring this discussion of Amsterdam together as a matrix of trade and risk-aversion?

A solution can be found in the spatial setting. The destinations in the prijscouranten – twenty in Europe and two in the West Indies – set formal horizons for navigation and shaped the range of premiums on offer. Thus it is possible to formulate the spectrum of insurance dealings in much the same way as the continuities around the ideal market of Johann Heinrich von Thünen. This would envisage a model with ‘broad bands’ – in the terminology of topologists – concentric on Amsterdam. They would co-ordinate season and climate, distance and political obligation into a dynamic system which converged during the optimal months of spring and summer. The spatial setting, therefore, formulates the interdependence of different categories of uncertainty, both structural and event.