In the 12th century, “[t]he pages were still made of parchment rather than of paper. The translucent sheep- or goatskin was covered with manuscript and brought to life in miniatures painted with thin brushes, The form of Perfect Wisdom could shine through these skins, bringing letter and symbols to light, and kindle the eye of the reader. To face a book was comparable to the experience one can live early in the morning in those Gothic churches in which the original windows have been preserved. When the sun rises, it brings to life the colors of the stained glass which before dawn had seemed like black stuffing in stone arches.”
Ivan Illich, In the Vineyard of the Text, The University of Chicago Press, 1996, p.17.