Herringbone naked structure

The goal of this paper is to show the geometric peculiarities identified in the dome of the church of Santa Maria in Ciel d’Oro in Montefiascone, built by Antonio da Sangallo the Younger, and to examine analogies and differences with the one included in the cathedral of Santa Maria del Fiore in Florence. The task pursued consists of an analysis of historical documents concerning the Sangallo's dome and in a photogrammetric survey of its intrados. The internal surface isn't plastered, therefore a lecture of the wall texture is possible. The survey has shown the geometry of the drawing of the various laying plans of the bricks, those horizontal face up laid touching the lines of the “parallels”, and the other edge on laid, placed according to the tangency of the “meridians”.