William Walker Atkinson 
Human Aura Astral Colors and Thought Forms 

The Aura is the invisible emanation radiating from every individual. An ethereal radiation. The egg-shaped human nebula. Psychic atmosphere sensed by everyone, but seen by but few. The clairvoyant vision. The phosphorescent flame, and luminous cloud. The colors in the aura and what they mean. Effect of mental states, emotion and passion, upon its aura. The human aura is a very important and interesting phase of every personality. The finer forces, the most powerful.This is one of the most necessary and helpful teachings for anyone interested in the occult. Far more than just ideas and words this is practical knowledge that when applied appropriately will change your world. (Goodreads)