Hans Vredeman de Vries, Perspective, part I: plate 50 (spiral staircases with sight lines and vanishing points marked, in outline and with detail and shading)

SOURCE: Hans Vredeman de Vries. Perspective (Leiden, 1604), part I, pl. 50 bound before pl. 35. This plate comes from Samuel Marolois, Opera mathematica (1614), part III NOTES: Parts III and IV of the Marolois Opera mathematica reproduced Vredeman de Vries's Perspective 'augmented and corrected in several places' by Marolois.