CANINE INFLAMMATORY MASTOID DISEASE. 
399 
that can with difficulty be estimated. The vital resources are 
sapped, wasted and frittered away generally, and a system already 
impoverished and drained must needs be further weakened by 
injudicious delay. 
To a query why inflammatory mastoid disease is so severe in 
its course and results, a critical examination of the parts involved 
j affords ample reply. Aside from the anatomical relations already 
noted are a complex system of veins ready and waiting to take up 
the poisonous materials and carry them to heart and lungs for 
elimination, and whence the surplus remaining is distributed to the 
whole economy in vain effort to find new outlets, we find an 
intricate net-work of nerve filaments constantly conveying morbid 
impressions and influences to the great nerve centres. The 
seventh pair of cranial nerves is primarily devoted to the uses 
(and abuses) of the auditory apparatus, while through its third 
branch, by way of the otic ganglion, th Q fifth -pair Bend minute fila¬ 
ments to meet those of the seventh in the innermost recesses of 
the mastoid cells, and we know full well that the burdens of any 
one nerve or series of nerves are in some degree borne by others, 
even those most remote. Again in mastoid disease the pus is 
enclosed in a dense bony case, and while it may, and sometimes 
does (though rarely), penetrate the external wall, it is still held 
in firm bondage by the interposition between it and the outer in- 
i tegumpnt, -first of a dense periosteum, and second by tendons even 
more impermeable. Though it is possible for tendons and 
periosteum to be torn from their attachments to the bone by 
3xcessive accumulations of purulent matter behind them, a terrible 
power is at the same time brought to bear upon the inner or cere¬ 
bral table of the mastoid, and if not interfered with, from the 
most favorable points of view a profuse abscess must result, ex¬ 
tending over a space two or three inches in diameter, burrowing 
downward and backward amidst the tissues of the neck. 
Whatever the character of aural disease, the local treatment 
should consist, from first to last, largely of hot water douches. 
With man we begin with water as hot as can be borne; but 
with the dog the process must needs be reversed. Commencing 
with fluid at about 90° Fh. the ear is carefully steadily syringed 
