Description: One of the four humors; natural chole (yellow bile) is the froth of blood; it is yellowish red, light, of hot and dry quality, and has a sharply strong taste. A part of it flows with blood and the other flows to the gall bladder. It assists the flow of blood through narrow vessels and is responsible for the nutrition of organs such as the lungs, and stimulates passing of urine and stool. Unnatural bile can be divided into varieties according to taste, odor, color and consistency.