Page:Vasari - Lives of the Most Excellent Painters, Sculptors, and Architects, volume 5.djvu/335

Rh the width of two of those pilasters which separate the windows placed under the vault of the Cupola at their base, but they constantly diminish up to the opening for the lantern: they rest on a pedestal of breadth equal to their own and twelve palms high, based on the platform of the cornice which passes around the tribune; over this and between the ribs are eight large ovals, each twenty-nine palms high, while above them is a range of rectangular compartments twenty-four palms high and somewhat broader at the lower than the upper edge; but where the ribs approach each other more nearly, then come circles, fourteen palms high, over each square, so that there are eight ovals, eight squares, and eight circles; each range being less deeply concave, as well as smaller than that beneath it: a most rich and beautiful design. Michelagnolo proposing to form the ribs, and framework of all these compartments in carved work of travertine.

There remains that we mention the superficies and ornaments of the exterior vaulting, which rises from a basement twenty-five palms and a half high, reposing on a socle which has a projection of two palms, as have the mouldings at the head. The master proposed to cover the whole roof with lead, as was done for the old Church of San Pietro, he divided it into sixteen spaces, which commence at the point where the double columns end, and are placed between them; in the centre of each space he formed two windows, making, thirtytwo in all, and serving to light the staircases between the two vaultings: to these he added projecting corbels supporting the segment of a circle; the whole forming a kind of roof which serves to throw off the rain. In the line of the columns and in the centre of the space between them, the ribs were made to spring from that point where the cornice ends, they were broader at the base and narrower at the summit; sixteen in all, and of five palms in width. In the centre of each there was a channel formed, a palm and a half broad, and in this were stairs of about a palm high, by which an ascent can be made to the opening left for the lantern. These are to be of travertine, constructed in such sort as shall defend them from the effects of the frost and rain.

The design for the Lantern makes that structure diminish