It is the extraction and distillation of essences of plants. Scientists have discovered that your nose-your olfactory system, relay-has a direct passageway to your brain. When you inhale the fragrance of a plant or its essential oil, you take in the gaseous molecules of that plant, and that causes a series of reaction in the brain, which in turn stimulate a series of reactions throughout the body. When the molecules are inhaled or massaged in to the body, they enter the bloodstream, therapeutically affecting the organs and glands of the body. Breathing in the essence of a flower or plant, you expose your brain to information that causes it to release endorphins and pheromones, which cause the rest of the body to be relaxed or stimulated, cooled or heated.