A nick name or stage name "Encyclopedia" seems to refer to someone who has the knowledge like an Encyclopedia. Doesn't it? In Korea, when someone is very smart, we sometimes says he is like a walking dictionary.
3)Leroy Brown, also known as Encyclopedia Brown, is a boy detective.
In this story, he helps his father, Chief of Idaville Police, solve the case of the stolen diamond necklace. Encyclopedia was reading about diamonds when his father, Chief Brown, entered his room.