476 DISEASES OF THE BRONCHI. 



occurs at those parts of the king-substance away from and not 

 acted upon by the bronchial inflammation. 



This state of pulmonary collapse, I have observed, is more 

 frequent in cases of secondary bronchitis, such as are asso- 

 ciated with certain specific and general diseases, also where 

 the vital powers of the animal seem invalidated by previous 

 disease, or by presently operating vitiating influences ; in such 

 the collapse may be extensive, although the obstruction appears 

 small. 



General Symptoms, a. Acute Bronchitis of the Large and 

 Small Tubes. — In the greater number of its forms of manifes- 

 tation bronchitis is preceded by febrile symptoms, although 

 in many these may be trivial, and are more commonly such as 

 are spoken of as indicative of a ' common cold ;' or the in- 

 flamed condition of the bronchial membrane may be ushered 

 into existence without previous indications of illness ; in such 

 the pyrexial symptoms will to a great extent be regulated by 

 the extent of the structures invaded. 



When fully developed we have, in addition to the sjnnptoms 

 of ordinary catarrh, should it follow that condition, a frequent, 

 short, rather hard cough, not markedly painful, with much 

 acceleration of breathing; the horse is dull and listless, not 

 much inclined to move, appetite impaired, and thirst in- 

 creased. As the disease becomes more confirmed, the cough 

 is more troublesome, occasionally paroxysmal, loud and 

 sonorous, particularly when the larger tubes are the seat of 

 the inflammation ; the pulse is increased in frequency and 

 rather soft, the respirations relatively more accelerated than 

 the pulse. 



On auscultating the chest the healthy respiratory sounds arc 

 found to have undergone considerable modification. When the 

 larger bronchi are specially the seat of the disease, we will, on 

 placing the ear over the anterior part of the chest, at the ter- 

 mination of the trachea, and less so at the upper and middle 

 third behind the scapula), hear a tolerably loud, sonorous 

 noise — ' rhonchus ;' if the inflammatory action is largely dis- 

 tributed through the smaller ramifications, the sound will, 

 where the unhealthy condition exists, be of a higher, shriller 

 pitch — ' sibilus.' Between these two extreme points there are 

 heard various modifications, according as the large or small 



