ARACHNITIS. 
315 
the causes which produced it, if they are known, as fractures, 
hydatids. See. The second is to prevent the disorganization of 
the brain: for this purpose general and repeated bleedings are 
used; the dashing of cold water, in which common salt has been 
dissolved, on the head; the establishment of some point of deri¬ 
vation ; some counter-irritant, as blisters on the inside of the 
thighs, or on the sides; or the use of the actual cautery: to 
these should be added, restricted diet, cooling drinks,and stimu¬ 
lating injections. If the disease continues long, and seems to be 
passing into a chronic state, purgatives should be employed in 
small doses and for a long continuance, and recourse may be had 
to setons in the neck and poll. 
Elemens de Pathologie Vtterinaire, p. 40. 
Acute Inflammation of the Arachnoid Membrane. 
Many causes may produce arachnitis or phrensy. The most 
usual, among the occasional ones, are blows on the cranium, 
exposure to the sun, acute or chronic inflammation of the brain, 
violent pain, stimulating food, the miasmata that produce typhus, 
inflammation of the mucous membrane of any of the digestive 
passages, or of any other mucous or serous membrane, and, 
finally, all the ordinary causes of inflammation. 
The symptoms are, violent convulsive action of the limbs, and 
forcible contraction of them, without being followed by palsy. 
The last symptom is seen only when the inflammation is propa¬ 
gated to the brain, or when there is serous effusion on the brain. 
The head is, at first, generally depressed; the horse rests it 
on his manger, or presses it against the wall. When he walks, 
the head is still carried low; it is struck against every object in 
the animal’s way, until he finds something against which he may 
press it. He staggers as he walks, his eyes are open and protrud¬ 
ing ; but he cannot see. By and by he becomes almost immoveable 
in some place vvhere he can partially support himself. All at 
once, however, violent convulsions succeed ; he strikes his head 
forcibly against every thing that surrounds him, without appear¬ 
ing to feel the blows he is inflicting on himself. He paws w'ith 
his fore-feet; he rears on his hind ones; he falls backward ; he 
struggles violently, and he sometimes dies in this state of exacer¬ 
bation. 
Prompt and copious bleedings are indicated; revulsives at the 
temples, thighs, and neck; the dashing of cold water on the 
head, and the application of ice to the forehead and poll. 
Chronic Arachnitis. 
This succeeds to acute arachnitis, or is from the commence¬ 
ment of a milder character than that which has been described. 
