APOPLEXY. 375 



stitial fluid within the spinal sheath. It is said that the 

 sanguineous congestion of the membranes often precedes 

 inflammation of the spinal cord itself, in which cases a 

 rapid paralysis follows. We are led to believe, the mem- 

 branes can inflame independently, and the same with regard 

 to the spinal cord ; also that each may be productive of a 

 series of symptoms of greater or less intensity. When the 

 substance both superiorly and inferiorhj is inflamed, then it 

 is usually found that both sensation and voluntary motion 

 are destroyed ; but "when the inflammation is limited to the 

 superior portion, the sensation is principally impaired ; and 

 when, on the contrary, the inferior half of the cord is 

 affected, then motion is prevented. A morbid alteration in 

 structure also takes place in the spinal cord ; this change 

 has been found in most domestic animals, as in rabies 

 in dogs, stomach staggers in horses, &c. The spinal cord 

 in these cases becomes soft, and converted into a gi-eyish 

 pulpy mass, losing its original fibrous structure, where 

 paralysis has been present. But we must not be misled by 

 this observ^ation to attribute all the affections of this class to 

 the spinal marrow : we attribute many of the most important 

 to morbid states of the cranial brain, as apoplexy, which is 

 attended with comp/e/e paralysis. Nor must we lose sight of 

 the retrograde march of some nervous irritations, which 

 spring from neither the cranium or spinal marrow ; but 

 originate in the extremities of the nerves, and are trans- 

 mitted to one or other, or to both the sources ; which 

 then become secondarily affected, as in the case of lock- 

 jaw, produced by wounds, &c. &c. 



APOPLEXY. 



Apoplexy does not very often occur in the horse ; but as 

 it does take place, although usually irremediable, it merits 

 a place in this treatise. It appears to consist in a lesion 

 of some of the vessels of the brain, which, by pouring out 

 their contents, produce pressure and irritation. Foreign 

 veterinarians have divided it, after the human, into san- 

 guineous and serous ; but as far as we have learned, it is the 

 former which has been principally met among horses. The 

 usual causes are such as, were it not for the length of the 

 neck, must operate more frequently than they do : these 



