Osservazioni sulla produttività del “buio” romanico: la finestra e la luce nell’architettura religiosa dell’arco sud-alpino

Starting from the realization – apparently taken for granted – of the darkness of some Romanesque churches, we investigate the possibilities and valences, both aesthetic and semantic, of the purposeful deployment of illumination into the interior of sacred space according to both the specific “direction” of daylight, and the revaluation of the effects of artificial illumination by means of oil lamps or candles. This essay concentrates on the window as indicator of the events of a microhistory of light in architecture. In a kind of close reading, we attempt to examine the diverse forms of an “economy of luminosity” determined by the arrangement, morphology, and transformations of the individual apertures of three churches of the Alpine foothill region of Lombardy from the 11th to the 12th century. Alongside techniques of directing the light into the churches’ interiors, we consider interventions towards the exclusion of daylight from sacred spaces. Until the last quarter of the Cinquecento, there does not seem to have been any need to attend to the apertures in order to augment their illumination. Only with post-Tridentine Reform and upon the publications of the Instructiones of Carlo Borromeo in 1577 was illumination increased by means of opening large oculi and windows, which the restoration campaigns of the 19th and 20th centuries have later obliterated