268 PNEUMONIA.— INFLAMMATION OF THE LUNGS. 



Here again the first step will be to bleed ; and here too will be the paramount 

 necessity of the personal attendance of some well-informed person while the 

 animal is bled. This is a disease of a mucous, — and an extended mucous surface ; 

 and while our measures must be prompt, there is a tendency to debility which 

 we should never forget. Although the horse may be distressed quite to the 

 extent which Mr. Charles Percivall describes, yet he would not bear the loss of 

 four pounds of blood without fainting. No determinate quantity of blood will 

 therefore be taken, but the vein will not be closed until the pulse falters, aid 

 the animal staggers, and in a minute or two would fall. This may probably 

 effect the desired object ; if it does not, it is possible that the practitioner may 

 not have a second opportunity. 



The medical attendant should be cautious in the administration of purgatives, 

 for the reasons that have again and again been stated ; but if the bowels are 

 evidently constipated, small doses of aloes must be given with the febrifuge 

 medicine, and their speedy action promoted by injections, so that a small quan- 

 tity may suffice. 



A blister is always indicated in bronchitis. It can never do harm, and it not 

 unfrequenly affords decided relief. It should extend over the brisket and sides, 

 and up the trachea to the larynx. The food, if the horse is disposed to eat, 

 should be mashes. No corn should be offered, nor should the horse be coaxed 

 to cat. 



PNEUMONIA— INFLAMMATION OF THE LUNGS. 



The intimate structure of the lungs has never been satisfactorily demon- 

 strated. They appear, however, to be composed of minute cells or pouches, 

 into which the air is at length conducted, and over the delicate membrane con- 

 stituting the divisions of which myriads of minute blood-vessels are ramifying. 

 The blood is not merely permeating them, but it is undergoing a vital change in 

 them ; there is a constant decomposition of the air, or of the blood, or of both ; 

 and, during the excitement of exercise, that decomposition proceeds with fearful 

 rapidity. Then it can readily be conceived that a membrane so delicate as this 

 must be, in order that its interposition shall be no hindrance to the arterialisation 

 of the blood ; so fragile also, and so loaded with blood-vessels, will be exceedingly 

 subject to inflammation, and that of a most dangerous character. 



Inflammation of the substance of the lungs is the not unfrequent conse- 

 quence of all the diseases of the respiratory passages that have been treated on. 

 Catarrh, influenza, bronchitis, if neglected or badly managed, or, sometimes 

 in spite of the most skilful treatment, will spread along the mucous membrane, 

 and at length involve the termination of the air-passages. At other times, there 

 is pure pneumonia. This cellular texture is the primary seat of inflammation. 

 It is often so in the over-worked horse. After a long and hard day's hunt, it 

 is very common for horses to be attacked by pure pneumonia. A prodigiously 

 increased quantity of blood is hurried through these small vessels, for the vast 

 expenditure of arterial blood in rapid progression must be provided for. These 

 minutest of the capillaries are distended and irritated, their contractile power 

 Is destroyed, inflammation is produced, mechanical injury is effected, the vessels 

 are ruptured, blood is poured into the interstitial texture, and intense inflamma- 

 tion and congestion, with all their train of fatal consequences, ensue. 



The following are the most frequent causes of pneumonia. A sudden tran- 

 sition from heat to cold ; a change from a warm stable to a colder one ; a 

 neglect of the usual clothing ; a neglect even of some little comforts ; riding 

 far and fast against a cold wind, especially in snowy weather ; loitering about 

 when unusual perspiration has been excited ; loitering tediously by the side of 

 a covert on a chilly blowing morning. 



