ACUTE CEREBRAL INFLAMMATION EMBRACING CEREBRITIS AND MENINGITIS. 627 
other diseases, and perhaps it was for this reason why I selected 
this subject. 
Under this heading we have encephalitis cerebritis or infla- 
mation of the substance of the brain, and meningitis or inflamma¬ 
tion of the coverings of the brain. The brain, the seat of animal 
life, is situated within the crainal cavity and covered or protected 
by three membranes, namely, dura mater, which lines the 
cranial cavity ; pia mater, which covers the brain in all its con¬ 
volutions, and the arachnoid, which is between these two. 
Inflammation is brought about in the brain and in these mem¬ 
branes in several different ways, as the result of direct violence 
to the bones of the cranium or some disease of those bones, as 
the result of some specific fever, from the entrance into the 
system of some specific virus, as in cerebro-spinal fever, or from 
exposure to the rays of the sun. The most common cause, how¬ 
ever, is from injuries to the cranial bones or disease of them, 
although we frequently see a sympathetic cerebral inflammation 
arising from some dietestic error. 
Much time has been spent in endeavoring to discover some 
diagnostic symptoms by which to distinguish cerebral from 
meningeal inflamation with some success ; but we find that in¬ 
flammation of the meninges quickly extends to the brain, and 
vice versa; therefore the distinction is not so desirable only so 
at the outset. 
Some of the diagnostic symptoms are those in Meningitis : 
when the membranes are primarily affected we see the animal 
in a very excited condition, frightened at every object and avoid¬ 
ing the attendant in every way possible; he is startled at any 
noise or bright light penetrating the stall; in fact, spasms or con¬ 
vulsions, pain and delirium are the general features of meningeal 
disease; following these symptoms are diminution or loss of 
nervous functions. 
In cerebral diseases we find the reverse of these symptoms, 
for from the outset or very early stages there is loss of one or 
more of the nervous functions, such as paralysis anaesthesia or 
loss of memory. The animal stands in a sleepy manner, with 
