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mal for several days, for it must be remembered that congestion may 

 be followed by pneumonia. The animal should have a comfortable 

 stall, where he will not be subjected to draughts or sudden changes of 

 temperature ; he should be blanketed and the legs kept bandaged. The 

 air should be pure, a plentiful supply of fresh cold water always before 

 him, and a diet composed principally of bran mashes, scalded oats, and 

 grass, if in season. When ready for use again he should at first receive 

 moderate exercise only, which may be daily increased until he may 

 safely be put at regular work. 



APOPLEXY OF THE LUNGS. 



This is but another term for congestion of the lungs, and for practi- 

 cal purposes needs no special description, except to remark that when a 

 hemorrhage occurs during the congested state of the lungs the blood 

 escapes from the ruptured vessels and extravasates into the lung tissue. 

 Such cases are called pulmonary apoplexy, and usually occur during 

 the course of some specific disease. 



PNEUMONIA — LUNG FEVER. 



Pneumonia may attack both lungs, but as a general rule one lung 

 only is affected, and in the great majority of cases it is the right lung. 

 The air-cells are the parts affected principally, but the minute branches 

 of the bronchial tubes always, to a greater or less extent, are involved 

 in the inflammation. Inflaoimation of the lungs occurs in three princi- 

 pal varieties, but in a work of this kind there is no necessity to dis- 

 crimiuate, and therefore the disease will be described under a common 

 head. It already has been mentioned that pneumonia may be compli- 

 cated with bronchitis, and it will hereafter be pointed out that it is very 

 commonly complicated with pleurisy. In this article the disease will 

 be considered mainly as an independent affection, and its complications 

 will be more fully described under separate heads. 



The inflammation usually begins in the lower part of the lung and 

 extends upwards. The first stage of the disease consists of congestion 

 or engorgement of the blood-vessels, and if this condition continues the 

 blood exudes from the vessels into the adjacent lung tissue; if rupture 

 of small blood vessels occurs there will be extravasations of blood in 

 the contiguous parts. The fluids thus escaping collect in the air-cells 

 and in the minute branches of the little bronchial tubes, and, becoming 

 coagulated there, completely block up the cells and exclude the air. 

 In this condition the lung is increased in volume and is much heavier, 

 and will sink in water. The pleura covering the affected parts is al- 

 ways more or less inflamed. A continuance of the foregoing phenom- 

 ena is marked by a further escape of the constituents of the blood, and 

 a change in the membrane of the cells, which become swollen. The 

 exudate that fills the air-cells and minute bronchial branches undergoes 

 disintegration, and is converted into a fatty material. The walls of the 

 cells almost invariably remain unaltered. 



It must not be imagined that the foregoing changes take place in 



