some round hole and studying the spot of light they form on a surface. A picture of a three-tiered camera obscura (see illustration) has been attributed to Bacon, but the source for this attribution is not given. A very similar picture is found in Athanasius Kircher's Ars Magna Lucis et Umbrae (1646). Polish friar, theologian, physicist, mathematician and natural philosopher Erazmus Ciołek Witelo (also known as Vitello Thuringopolonis and by many different spellings of the name "Witelo") wrote about the camera obscura in his very influential treatise Perspectiva (circa 1270–1278), which was largely based on Ibn al-Haytham's work. English archbishop and scholar John Peckham (circa 1230 – 1292) wrote about the camera obscura in his Tractatus de Perspectiva (circa 1269–1277) and Perspectiva communis (circa 1277–79), falsely arguing that light gradually forms the circular shape after passing through the aperture. His writings were influenced by Roger Bacon. At the end of the 13th century, Arnaldus de Villa Nova is credited with using a camera obscura to project live performances for entertainment. French astronomer Guillaume de Saint-Cloud suggested in his 1292 work Almanach Planetarum that the eccentricity of the sun could be determined with the camera obscura from the inverse proportion between the distances and the apparent solar diameters at apogee and perigee. Kamāl al-Dīn al-Fārisī (1267–1319) described in his 1309 work Kitab Tanqih al-Manazir (The Revision of the Optics) how he experimented with a glass sphere filled with water in a camera obscura with a controlled aperture and found that the colors of the rainbow are phenomena of the decomposition of light. French Jewish philosopher, mathematician, physicist and astronomer/astrologer Levi ben Gershon (1288–1344) (also known as Gersonides or Leo de Balneolis) made several astronomical observations using a camera obscura with a Jacob's staff, describing methods to measure the angular diameters of the sun, the moon and the bright planets Venus and Jupiter. He determined the eccentricity of the sun based on his observations of the summer and winter solstices in 1334. Levi also noted how the size of the aperture determined the size of the projected image. He wrote about his findings in Hebrew in his treatise Sefer Milhamot Ha-Shem (The Wars of the Lord) Book V Chapters 5 and 9. 1450 to 1600: Depiction, lenses, drawing aid, mirrors Italian polymath Leonardo da Vinci (1452–1519), familiar with the work of Alhazen in Latin translation, and after an extensive study of optics