568 CEOUP. 



by altering the condition of the mucous membrane, and 

 bringing about a condition incapable of sustaining the 

 peculiar exudation." 



FEACTUEE OF THE WINDPIPE. 



Accidents to the trachea are rare, considering its exposed 

 position. This is accounted for by its elasticity and the 

 readiness with which the windpipe moves from one side of 

 the neck to the other. Nevertheless, blows and wounds are 

 occasionally causes of injury to the cartilaginous rings of the 

 trachea, and the principal inconvenience resulting consists in 

 a very general emphysema of the neck and body. Air passes 

 into the surrounding areolar tissue, and gives the animal a 

 very peculiar and alarming appearance. 



Little more can be done in such cases than keeping the 

 animal quiet. Should any symptoms of suffocation appear, 

 tracheotomy must be performed. A dose of purgative medi- 

 cine may be administered. 



DISEASES OF THE LUNGS. 



CONGESTION PULMONAEY APOPLEXY. 



The lungs are extremely vascular, and are not unfrequently 

 subject to irregularities in the flow of blood through them. 

 In horses which are often exhausted by reckless and pro- 

 longed driving or riding, nothing is more common than 

 a sudden and fatal engorgement of the lungs. This may in 

 some cases be the precursor of a well-developed bronchitis 

 or pneumonia, but not unfrequently terminates fatally before 

 the development of a true inflammatory disease. I cannot 

 refer to this subject without noticing the practical observa- 



