September 18, 2017 Leaf 3 3. A leaf with a Medieval text attributed to Albertus Magnus (c. 1200 – November 15, 1280). Also known as Saint Albert the Great, Albert was a German Dominican friar and Catholic bishop. Later canonized as a Catholic saint, he was known during his lifetime as the greatest German philosopher and theologian of the Middle Ages. The leaf is likely from his work on astrology titled, Speculum Astronomiae (1260), as the text focuses on phases of the Moon. Leaf 10