The Library's brand, as registered with the Idaho State Brand Board (a subset of the Idaho State Police) is described as "M P L connected with a rocker." If you understand brand descriptions you will be able to instantly visualize it.

Kinda like "Vert, a wolf statant ululant and on a chief embattled argent three dolphins azure" or "Per bend sinister azure and gules, a bend sinister Or between two needles in saltire threaded with a single thread argent and three apples Or."