The Book of Signs contains 493 classified and documented illustrations, collected, drawn, and explained by the celebrated typographer Rudolf Koch. Divided into 14 different categories, it includes General Signs, The Cross, Monogram of Christ, Other Christian Signs, Monograms of Medieval Church and State Leaders, Stone Masons' Signs, The Four Elements, Astronomical Signs, Astrological Signs, Botanical Signs, Chemical Signs, House and Holding Marks, Miscellany, and Runes.