CONGESTION OF THE LUNGS, 



479 



It is first an increased action of the blood-vessels. The conse- 

 quence is an increased amount of blood, to the part. The next 

 change to take place is a collapsed condition of the walls of the ves- 

 sels. Now there follows an enlargement of the blobdr-vessels ; then 

 the blood passes the walls of the vessels through the tissues outside 

 of the vessels. The next change isthe breaking down of the cellular 

 tissues — normal cell's ; next a rapid growth or proliferation of ab- 

 normal cells. To go through symptoms : If an external injury, 

 for example, there would be, first, pain caused by the pressure 

 upon the nerves. The heat following would be caused by the 



Fio. 800. — Bronchial Tube, with its Bronchules and Ultimate Ramifications. Natural Size. 



chemical changes that are going on within the part. The redness 

 is due to the passing of the blood from the vessels into the tissues ; 

 the swelling is' due to the breaking down of normal cells and the 

 rapid formation of abnormal cells. The object in all cases, whether 

 internal or external, is to equalize the circulation as quickly as 

 possible. 



There are two methods of treatment: If we know the cause, 

 as, for example, the animal having stood in a draught of air or 

 been exposed to cold, chilling weather, alcoholic stimulants would 

 be the best treatment, not only giving alcohol internally, but rub- 

 bing it on the legs, and covering the body with warm blankets. 

 Rub the elbows and hdcks to the feet, with the hand or a brush, 



