14 ARACHNOIDITIS. 



knowledging how difficult it is, admitting them to have a separate 

 existence, to distinguish between them, has laid down the follow- 

 ing rules for our guidance : — '' Apoplexy appears to be generally 

 characterised by sudden loss of power over the voluntary muscles, 

 without spasmodic action. Inflammation of the brain is known by 

 spasmodic action followed by slow and progressive, perhaps irre- 

 gular and intermittent, paralysis. Arachnoiditis, by spasmodic ac- 

 tion without loss of voluntary power." 



So far from there being any paralytic tendency in mad staggers, 

 we know that the powers of voluntary motion, while the paroxysm 

 rages, are excited and increased to their utmost degree, although 

 the sensibility, especially in the intervals between the fits, appears 

 dead to all external imoression, and the faculties of the ors^ans of 

 sense we know to be lost : at least, so it is with the eyes, and so 

 we conclude it to be with the ears and other senses. This, then, it 

 seems agreed, constitutes the membranous inflammation ; the sub- 

 stance of the brain itself exhibiting — to borrow the language of 

 the great CuUen — ''as in other analogous cases, a more chronic in- 

 flammation." 



The Causes of Staggers comprise any and every thing 

 which has tendency to produce an overflow of blood upon the 

 brain; such as plethora of body, inordinate exertion, sultry weather, 

 and determination of blood to the head from peculiar conformation of 

 parts or other cause. Horses at the middle or most robust period 

 of life, in full or gross condition, with short, bull-like, straight necks, 

 and but very inadequately or irregularly worked, are the common 

 subjects of staggers. The disease may arise suddenly from a sort 

 of couj) de soleil. Soon after my father entered the Ordnance 

 Service at Woolwich, it became customary to turn horses who had 

 become low in condition, and stale upon their legs from work, from 

 out of the Barracks at Woolwich into the Plumstead Marshes, to 

 recruit their strength. During the months of July, August, and 

 September, no case was more common than an attack of staggers 

 among these horses ; which my father attributed to the luxuriant 

 pasture they were suddenly turned into — for it invariably loaded 

 them with fat, and consequently plethorized their systems — com- 

 bined with the dependent posture of the head, and Ike sultry heal 



