SECRETARY'S REPORT. 149 



or described. It is so insidious in its approach, that it may 

 remain in the herd for some time before it is discovered, and 

 then it will probably be too late to effect a cure. Indeed after 

 it has passed its first stage and become seated upon the animal, 

 it is either wholly incurable, or if an apparent cure is effected, 

 it will turn out, in the end, that the first loss would have been 

 the best, and that all infected animals ought to have been at 

 once destroyed. 



This dangerous disease derives its name from the parts 

 affected, the pleura being the lining membrane of the lungs, 

 and pneumonia the substance of the lung itself. The lungs are 

 found, on a post mortem examination, to have lost their light, 

 porous consistence, and their pinkish color, and to have become 

 condensed or filled with lymph, dark or nearly black, imper- 

 vious to air, and of course incapable of expansion and contrac- 

 tion, and of oxygenating or vitalizing the blood. 



The first symptom that will be likely to attract attention will 

 be a dry, husky cough, which is more and more perceptible after 

 the animal has been watered or moved, or in any way excited. 

 After a time the appetite falls off, rumination ceases, the coat 

 becomes staring, the temperature over different parts of the 

 skin and the external surfaces is unequal, the horns may be 

 hot and cold alternately, or one part of the body may be very 

 warm and feverish at the same time that the other is cold ; the 

 respiration is quickened and more labored, the pulse quickens, 

 the flesh rapidly falls off, the nostrils begin to discharge a 

 lightish substance, till finally the breathing grows shorter and 

 gasping, the breath itself becomes fetid and insupportable, and 

 the poor creature dies. 



The contagion appears to be communicated by an animal 

 poison in the air, proceeding from the lungs and breath or the 

 respiratory surfaces of a diseased animal, and another animal 

 coming in contact or within the influence of this vitiated air, is 

 very liable to be infected. It attacks old animals and young, 

 cows in milk, or otherwise, calves and oxen, indiscriminately, 

 but does not extend to horses, or any but neat stock. Its out- 

 break in any herd can be traced directly to the introduction 

 into it of cattle from some infected herd, and its spread and 

 extension can only be prevented by the immediate and com- 

 plete isolation of the infected animals from others, or the 



