The curtain has plenty of space for the troops' convenience, and provides an outlet for the fumes and the thunder of the guns. The model shown here features innovative roofing. . Manuscript L , folio 48 r. The folio comprises drawings of fortifications, which can be dated around 1502. They illustrate a study of a curtain with buttresses and semicircular salients.
Top right is an orthograph of a curtain with buttresses and convex roofing.
Bottom left are three sketches depicting a cutaway view of the buttresses.