Sistine Chapel ceiling how the work progressed. It was customary for fresco painters to use a full-sized detailed drawing, a "cartoon", to transfer a design onto a plaster surface—many frescoes show little holes made with a stiletto, outlining the figures. Here Michelangelo broke with convention; once confident the "intonaco" had been well applied, he drew directly onto the ceiling. His energetic sweeping outlines can be seen scraped into some of the surfaces, while on others a grid is evident, indicating that he enlarged directly onto the ceiling from a small drawing. Michelangelo painted onto the damp plaster using a wash technique to apply
The Birth of Venus Politian speaks of Zephyr causing flowers to bloom, and spreading their scent over the land, which probably explains the roses he blows along with him in the painting. Having a large standing female nude as the central focus was unprecedented in post-classical Western painting, and certainly drew on the classical sculptures which were coming to light in this period, especially in Rome, where Botticelli had spent 1481–82 working on the walls of the Sistine Chapel. The pose of Botticelli's "Venus" follows the Venus Pudica ("Venus of Modesty") type from classical antiquity, where the hands are held to cover the breasts