Marijuana Linked to Early Gum Disease. Feb. 5, 2008 -- Gum disease is widely considered a disease of aging, but that may not be true for young adults who smoke marijuana on a regular basis.
Your third eye is located in the center of your forehead. It is the site of the ajna chakra, which is associated with light, perception, and intuition. Chakras can become unbalanced when they are blocked, which may cause a person to feel like the areas influenced by that chakra are not working properly.
The third ray, the focal ray, is a mirror image of the parallel ray. The focal ray is drawn from the tip of the object through (or towards) the focal point, reflecting off the mirror parallel to the principal axis. All three rays should meet at the same point.