"Even those with only a superficial; knowledge of architectural history texts have certainly come across the so-called 'regulating lines', those complex grids of lines, circles and arcs superimposed onto buildin elevations or—more rarely—onto building plans. Their meaning should be fairly transparent: they demonstrate the presence of a system of special proportional relationship that would otherwise remain hidden to the naked eye without the subtleties of geometry. It is no coincidence that they can be found predominantly in texts about Renaissance architecture, or—as critical tradition would have it—about the period that perhaps more than any other posed the mathematical precision of proportions at the centre of its aesthetic conceptions."
A Regulated Suasion: The Regulating Lines of Francesco di Giorgio and Philibert de l'Orme
Giovanni Galli
Journal of the Warburg and Courtauld Institutes
Vol. 65 (2002), pp. 95-131
