Mosaics honoring the humanities and science flank the entrance of the Montebello Library on Beverly Blvd. They were installed in 1966, when this building went up. Before that, the Montebello Library had four other locations since being established in 1914.
The artist is Livio Napolitani, whose work graces another librairies in Los Angeles County (Gardena) that I'll get to another week.
The trees in each mosaic symbolize human ignorance, according to the LA County Arts Website--a great resource for locating public art in Los Angeles.