501 



two stalls, but sometimes several stables away. When the stable was 

 remodeled and new woodwork was placed in for mangers and floors the 

 disease disappeared. The virus is but moderately volatile, and in a 

 stable seems rather to follow the lines of the walls and irregular courses 

 than the direct currents of air and the tracts of ventilation. Professor 

 Dieckerhoff found that the contagion of influenza was readily diffusi- 

 ble throughout an entire stable and through any opening to other build- 

 ings, and substantiates the writer's experience that it will pass through 

 solid walls of considerable thickness ; but he also found that the con- 

 tagion of cedemateous i)neumonia is not transmissible at any great dis- 

 tance, nor is it very diffusible in the atmosphere. A brick wall 8 feet in 

 height served to prevent the infection of other animals placed on that 

 side of a horse ill with the disease, while others placed on the opposite 

 side and separated from the focus of contagion only by open bars in 

 the stall, were infected and developed the disease in its typical form. 



Symptoms.— The symptoms differ slightly from those of a frank, flbri- 

 nous pneumonia, but not so much by the introduction of new symptoms 

 as by the want of or absence of the distinct evidences of local lesions 

 which are found in the latter disease. All of the pneumonias through- 

 out the whole course of the trouble are less marked and less clearly 



deiined, 



At first the symptoms are latent; the animal gives a rare cough 



which resembles that of a heavy horse affected with a slight chronic 

 bronchitis; it becomes somewhat dejected and dull, at times somnolent, 

 and has a diminished appetite. This condition lasts for several days. 

 No history can be obtained of causes for symptoms of acute troul)le, 

 and the absence of organic lesions to account for the general condition 

 leaves the attendant, however expert he may be, in much doubt as to 

 the nature of the trouble unless previous cases in the same stable, or 

 special tact on the part of the veterinarian, aids in foreseeing the prob- 

 able termination of the slight local trouble and commencing adynamic 

 changes in the organic functions of the animal. No crepitant rale is 

 heard as in fibrinous pneumonia, as in this disease the local trouble 

 commences in the neighborhood of the large air tubes and not on the 

 periphery of the lungs. During several days these symptoms increase 

 and a fever of a low type gradually develops. The respiration in- 

 creases to twenty-four, thirty, or thirty-six to the minute, and a small, 

 running, soft pulse, indicating great exhaustion of the capillaries and 

 their surrounding tissues, attains a rhythm of fifty, seventy, or even more 

 beats in the sixty seconds. The heart, however, contrary to the debil- 

 itated condition of the pulse, is found beating violently and tumultu- 

 ously, like it does in anthrax and septic intoxication. The mucous 

 membranes of the eyes and mouth and of the genital organs are found 

 somewhat oedematous, and they rapidly assume a dirty, saffron color, 

 at times approaching an ocher, but distinguishable from the similar 

 coloration in influenza by the want of the luster belonging to the latter 



