SECTION II. 

 DISEASES OF THE TRACHEA AND BRONCHI. 



CflAPTEK I. 



DYPER^EMIA AND CATARRH OP THE AIR- PASS AGES AND BRONCHIA/ 

 MUCOUS MEMBRANE. 



ETIOLOGY. "We have already stated that every considerable hyper- 

 remia gives rise to a series of nutritive and functional disorders, known 

 as catarrh ; and that, if catarrh be included among the inflammatory 

 affections, the terms hypersemia and inflammation must be regarded as 

 synonymous, although the words are not generally considered identical 

 in meaning. 



Predisposition to catarrh of the bronchial mucous membrane is as 

 variable as is predisposition to catarrh of the larynx, developing either 

 readily, or with difficulty, from the same causes, according to individ- 

 ual peculiarity. " An increased susceptibility of the skin to change of 

 temperature," or an "augmented vulnerability of the mucous mem- 

 branes," is simply an hypothetical assumption to which we have recourse, 

 where no other explanation is at hand, to account for the excessive 

 liability in certain persons to suffer from catarrh of the bronchi upon 

 slight exposure. Experience, however, permits us to bring forward 

 certain particular conditions as predisposing causes. In the first place, 

 in childhood, and especially during the period of dentition, there is a 

 strong tendency to catarrh of the mucous membrane in general and of 

 the bronchi in particular. We daily hear it said that children have 

 "a tooth-cough," and hear intestinal catarrh of this period called a 

 " tooth-diarrhoea," 



In middle age this predisposition diminishes ; in old age, again, it i? 

 more marked, senile chronic catarrh becoming a most frequent com 

 plaint, and furnishing a large contingent to the hospitals and infirmaries. 

 Secondly : badly-fed, flabby individuals show unmistakable general pre- 



