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an instrument called tbe stethoscope is employed. The former is the 

 best mode for horses. In order to gain any satisfaction or knowledge 

 by the practice of this method the reader must first become familiar 

 with the sounds in a healthy horse, which can only be learned by prac- 

 tice. Much more practice and knowledge are then required to discrimi- 

 nate properly between abnormal sounds and their significance. 



Percussion. — As applied to the practice of medicine this term refers 

 to the act of striking on some part of the body to determine the condi- 

 tion of the internal organs by the sound elicited. If a wall of a cavity is 

 struck the sound is easily distinguished from that emitted when a solid 

 substance is knocked on. When percussing the chest, the ribs are 

 struck with the tips of the fingers and thumb held together, or with 

 the knuckles. An instrument called the pleximeter is sometimes laid 

 against the part, to strike on. If the surface is soft over the part to be 

 percussed, the left hand is pressed against it firmly, and the middle fin- 

 ger of it struck with the ends of the fingers of the right hand to bring 

 out the sound. This method of examination also requires much prac- 

 tice on the healthy as well as the unhealthy animal. 



BRONCHITIS. 



As previously described, the windpipe terminates by dividing into 

 the right and left bronchi, running to the right and left lung, respect- 

 ively. After reaching the lungs these tubes divide into innumerable 

 branches, gradully decreasing in size, which penetrate all parts of the 

 lungs, ultimately terminating in the air-cells. Tbe bronchial tubes are 

 formed much the same as the windpipe, consisting of a base of carti- 

 laginous rings with a layer of fibrous and muscular tissue, and lined in- 

 ternally with a continuation of the respiratory mucous membrane. 



Bronchitis is an inflammation of the bronchial tubes. The mucous 

 membrane alone may be afiected, or the inflammation may involve the 

 whole tube. Bronchitis aifecting the larger tubes is less serious than 

 when the smaller are involved. The disease may be either acute or 

 chronic. The causes are generally much the same as for other diseases 

 of the respiratory organs, noticed in the beginning of this article. The 

 special causes are: The inhalation of irritating gases and smoke, and 

 fluids or solids gaining access to the parts. Bronchitis is occasionally 

 associated with influenza and other specific fevers. It also supervenes 

 on common cold or sore throat. 



Synqytoms. — The animal appears dull ; the appetite is partially or 

 wholly lost; the head hangs; the breathing is very much quickened; 

 the cough, at first dry, and having somewhat the character of a "bark- 

 ing cough," is succeeded in a few days by a moist rattling cough ; the 

 mouth is hot; the visible membranes in the nose are red; the pulse is 

 frequent, and during the first stage is hard and quick, but as the dis- 

 ease advances becomes smaller and more frequent. After a few days a 

 whitish discharge from the nostrils ensues ; sometimes this discharge 



