• Dry  tongue means Lung, 
• Dry and very coarse means fever is Lung fever 
• Both Lung and Fever the same, dry and blackish 

Crack down the middle of tongue means a disorder of Lung. Channels support the winds, winds support the mind, mind the heart, stress disorders - high blood pressure.
CAUSE: Thought to be leading a life at variance with one's spiritual longing. Worry, overwork, sorrow, anger 

Red, rough, dry, DECREASE of Lung, Reddish and dry - Lung/Tipa 

Pale and dry - Lung/Badkhen 

Pale means ongoing Fever which has spread to all channels 

HEALTHY TONGUE -  not too reddish, little coating