BRONCHITIS. 95 



and all but inaudible murmur^ we sball perceive a distinct 

 sound^ a cooing sort of noise, arising from want of secretion 

 within the tubes. When the secretion returns_, and in 

 augmented quantity, we shall distinctly hear the rale or 

 rattle as it is called. These sounds will, of course,, be 

 present only in places where the disease is present, and in 

 one or both lungs, according as the case may happen to be. 



Progress. — The disease in its acute form attains its 

 height commonly about the fourth or fifth day, and after 

 the sixth or seventh begins to decline, leaving the patient 

 out of danger at the expiration of the tenth or twelfth. 

 Should the case not go on favorably, however, about the 

 fifth or seventh or ninth day, when acute, we may look for 

 decline into pulmonic or pleuro-pulmonic disease, if not, 

 in consequence of sufi*ocation, into death itself. The signs 

 of growing worse are — the respiration becoming very op- 

 pressed; the pulse quicker and fainter; the skin and 

 extremities cold ; the mouth cold and clammy; and the 

 nostrils dry, lacking any moisture whatever. 



The PROGNOSIS is in general favorable. Bronchitis is 

 dangerous only when the secretions clog or obstruct the 

 tubes ; or in its 



Complicated forms, as when combined with other 

 disease of the lung, and with pleurisy. Especially dangerous 

 is it when combined with disorder of the mucous lining of the 

 alimentary canal. In this latter case, in combination with 

 diarrhoea, and when the inflammation is running high in 

 the bronchial membrane, there is hardly a chance of saving 

 the animal. 



Pathology. — In the advanced condition of veterinary 

 science of the present day, bronchitis is no longer con- 

 founded with inflammation of the substance of the lungs: 

 the structures are entirely different ; the tissues in which 

 the inflammation is seated so difibrent that diff'erent eff'ects 

 are produced, and different terminations come to. The 

 bronchi, like the windpipe and larynx, are lined by a 

 secreting membrane which inflammation or irritation may 

 simply augment the secretion of, or may run so high in as 

 nearly or altogether to suppress it; and these changes of action 



