rXEUxMONIA.-— INFLAMMATION OF THE LUNGS. 283 



membranes of the air-cells or divisions which they contain. _ There is 

 metastasis of inflammation oftener here than in pure pneumonia, and the 

 disease is sometimes transferred to the feet. If, however, there is neither 

 pneumonia nor metastasis of inflammation, and the disease pursues its 

 course, the animal dies from suffocation. If the air-passages are clogged, 

 there can be no supply of arterialised blood. If the inflammation be sub- 

 dued, resolution may" take place : but it far more frequently assumes a 

 chronic form, giving rise to an imperfect state of breathing knoAvn as 

 ' thick wind.' . . . 



Like every other inflammation of the respiratory passages, bronchitis is 

 at times epidemic. There is a disposition to inflammation in the respira- 

 tory apparatus generally, but it depends on some unknown atmospheric 

 influence whether this shall take on the form of catarrh, bronchitis, or 

 pneumonia. It is not, however, contagious. 



This is a disease of the mucous, — and an extended mucous, — surface; and 

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

 we should never forget : therefore bleeding should not be had recourse to. 



The medical attendant should be also cautious in the administration of 

 pitrgatives, for the reasons that have again and again been stated : but if 

 the bowels are evidently constipated, half a pint of oil may be given, and 

 its speedy action promoted by injections, so that a small quantity may 

 suf&ce. Sedatives should be employed, as 5i. to 5ij. of extract of bella- 

 donna, in combination with spirits of nitric ether and hquor ammonii© 

 acetatis. The animal should be placed in a warm, but well-ventilated 

 stable, and the extremities kept warm by friction and flannel bandages. 



A blister is always indicated in bronchitis. It can never do harm, and 

 it not unfrequently aflTords 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 ofi"ered, 

 nor should the horse be coaxed to eat. 



PNEUMONIA. INFLAMMATION OF THE LUNGS. 



The ultimate structure of the bugs has never till lately been satisfac- 

 torily demonstrated. They appear, however, to be composed of minute 

 cells or pouches, into which the air is conducted, and over the delicate 

 membrane constituting 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 decompositioi} proceeds ^ith fearful rapidity. Then it can readily be 

 conceived that a membrane so delicate as this must be, in order that its 

 interposition should be no hindrance to the arterialisation of the blood— so 

 fragile also, and so loaded ^vith 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. The 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 progress must be provided for. These minutest of 

 the capillaries are distended and irritated, their contractile power is 



