Inspired by the Holy Spirit (in the form of a dove), Pope Gregory I dictates holy decrees to a deacon. Illuminated parchment created in Altzella Abbey in the 11th century from Leipzig university library. Chromolithograph from Hefner-Alteneck's "Costumes, Artworks and Appliances from the Middle Ages to the 17th Century," Frankfurt, 1879. Illustration by Dr. Jakob Heinrich von Hefner-Alteneck, lithographed by C.R., and published by Heinrich Keller. Hefner-Alteneck (1811 - 1903) was a German museum curator, archaeologist, art historian, illustrator and etcher.