276 VETERINARY MEDICINE AND SURGERY. 



■will be advisable to administer tincture of aconite, twenty drops in water 

 every four or five hours. 



PURPURA HEMORRHAGICA. 



Synonyms. — Spotted fever; Cliarbon. 



Definition. — An eruptive non-contagious fever, characterized by the 

 appearance of petechial or blood spots upon the mucous membranes. 



Etiology. — It is usually the sequel of some other disease, in conse- 

 quence of keeping the horse in a debilitated condition, in badly drained 

 and ventilated stables. It rarely occurs where pure air, clean floors, and 

 abundant ventilation are provided. 



Symptoms. — Usually the earliest symptom which awakens our sus- 

 picion, or which yields indications of the onset of purpura, is tha 

 appearance of the local swellings. These swellings are diagnostic; they 

 are sudden in their appearance, occurring in different parts of the body, 

 generally the limbs, the abdomen, or the head, particularly the inferior 

 portion of the face and around the nostrils and mouth. They are some- 

 times limited or in patches, often uniform when in connection with the 

 limbs, always elevated above the level of the surrounding skin, and 

 terminating abruptly, not gradually by shading off into the level of sur- 

 rounding parts. They are tense, pitting slightly on pressure, but neither 

 very hot nor very painful. 



Very early in the course of the disease, or it may be delayed for some 

 time, the condition of the lining membrane of the nasal cavities is al- 

 tered. It is at first merely heightened in color, and studded with pete- 

 chise, which gradually extend, chiefly by coalescing, until they cover the 

 greater portion of the septum which is visible, and steadily assume a 

 darker color; or they may be observed to alter in color, as also in extent, 

 with the changes and remissions of the other symptoms. When these 

 blood-spots and submucous blood-extravasations are fairly established in 

 connection with the nasal structures, we observe that a sero-sanguineous 

 fluid, or blood, of a darker color than natural, and not disposed to coag- 

 ulate, trickles from the nostrils. 



From the infiltration of the subcutaneous tissue of the external, and 

 the submucous of the upper and internal air-passages, and consequent 



