Both the Heart and Lung inhabit the Upper Burner, which is in the most Yang region of the body. The Heart corresponds to Fire (Yang) and the Lung to Metal (Yin). The Heart governs the perfusion of Blood (Yin), while the Lung governs the perfusion of Qi (Yang). Both the Heart and Lung are vulnerable to Heat and Dryness, especially the Lung which perfers coolness and moistness.* The nature of the Heart is expansive and diffusing, propelling blood to the surface where it releases its Qi through radiant heat and perspiration. The nature of the Lung in contractive and descending: it tightens the skin while sucking the moist Qi of the air inward, precipitating it downward to be combined with the Essence (Jing) of the Kidney. When the relationship between the Heart and Lung is disturbed, the circulation of Qi, Moisture, and Blood becomes disorganized, leading to an instability of temperature and humidity at the body's surface and core.* Harmonize Heart & Lung tonifies Blood and Moisture, consolidates Qi and Moisture, disperses Qi and Blood, dispels Heat and Phlegm, and calms the mind.*