Title page of Ars magna lucis et umbrae (Great Art of Light and Shadow) by Athanasius Kircher, published at Rome in 1646. Light rays are seen reflecting from mirrors to illuminate in different ways. At the top are Hebrew characters signifying God, with angels below. At left is a figure representing the day, at right clothed in stars is the night. Below centre if a portrait of Emperor Ferdinand II, next to whom is a Hapsburg double-headed eagle.