One of the most important books in Western Art was written in 1593 by an Italian butler during his spare time while working in the private household of a cardinal in Rome. Cesare Ripa's Iconologia heavily influenced painting, design, music, poetry, architecture etc for centuries. 
Ripa scoured libraries for everything he could find on Egyptian, Greek, Roman, Medieval symbology and collected them in an easy to use book. When he added illustrations to the second edition it became an instant best seller influencing every classical artist well into the 20th c.
Us moderns who do not know Iconologia can not make sense of any classical art or decoration, especially in monuments, or Baroque and Rococo art. A famous example is Vermeer's the Art Of Painting, where Clio—the muse of history—is being modeled, holding a scroll and trombone...
...which follows the text and illustrations of Cesare Ripa perfectly. Here is a later French 18th century print of Clio, "the proclaimer, glorifier and celebrator of history, great deeds and accomplishments": hence the book (to preserve) and the trumpet (to proclaim).
Here is how Ripa portrayed Beauty: "A Woman... Beauty is depicted with her head hidden among clouds, since it is not a thing to be talked about by mortals and less to be known by human brain."
And in her hand, the eternal symbol of Beauty, the white lily: “...as the lily moving sense and awake spirits by means of the smell acuteness, so beauty moves and awakes souls to love and delight.”
“In the other hand she shall hold a ball with a pair of compasses to demonstrate that every beauty is constituted by measures and proportions, that agree with time and place...cause the beauty to be spread in the architecture of all things subjected to the human eye...”
