DISEASES OF THE RESPIRATORY ORGANS. 131 



sides, and tlie fluid is reabsorbed, the two layers come into 

 contact, and the friction is heard again, and is termed 

 *redux friction.' 



Other Sounds sometimes heard in Auscultating the 

 Chest under Certain Conditions. — Metallic Tinkling 

 is a sound caused by drops of fluid falling from the walls 

 of a cavity into the fluid below. It resembles the sound 

 produced by drops of water falling into a well. 



Gurgling Sounds are due to the liberation of air-bubbles 

 from eff'used material. 



Cough Resonance. — If we listen to the walls of the chest 

 of a healthy horse, as he coughs the sound is heard as being 

 of a soft, dull, indistinct character. 



In pulmonary disease the character of this cough reson- 

 ance is altered. For instance, in hepatisation, or compres- 

 sion of the lung from eff'usion, if the horse be made to 

 cough while we listen to the chest, the sound produced is 

 much louder and more distinct and harder over the 

 involved area than in the normal condition. 



CERTAIN SYMPTOMS ASSOCIATED WITH 

 DISORDER OF THE RESPIRATORY ORGANS. 



GRUNTING. — If a horse when struck or suddenly 

 moved makes, during ex23iration, a grunting noise, he is 

 said to be a ' grunter.' The emission of this sound is 

 always to be looked upon with suspicion, as it generally 

 accompanies whistling and roaring. It may or may not be 

 due to disease of the larynx. A horse may grunt from 

 pain, when suff'ering from pleurisy, pleurodynia, and other 

 disorders, and some horses grunt when struck at or moved 

 suddenly. 



9—2 



