(2)        Moisture:  the tongue coating is considered healthily moist, when it is neither too dry nor too wet.  The body fluid is sufficient.  However, it is considered excessively wet, if when one scours it, it is watery or even dripping.        If the tongue is too dry, there is no sign of fluid when scoured.     This is caused by the inability of the fluid to rise up to feed the upper part of body.  This is usually caused by excessive heat that reduces fluid, by the lack of Yin fluid, or deficiency of Yang Qi to convert water into fluid, and the dry late Summer Qi which tends to hurt the lung.  When the coating changes from moist to wet, it indicates that the state of health is getting worse; on the other hand if the tongue coating changes from a dry one to a moist tongue, and follow by a receding of heat and a return of fluid level, it indicates recovery is on the way.