OBSERVATIONS MADE IN CANINE MEDICINR. 
313 
all cases to set up otitis ; in other words, I am convinced that 
any organism which can thus break np the ear secretions and 
accumulations is capable of producing this eczema. 
I am accustomed to compute the gravity of these individual 
cases greatly by this test, as experience has taught me to con¬ 
sider those which give free ammonia as scarcely ever belonging 
to the chronic form, where so much structural and functional 
change has occurred as to place the question of permanent cure 
in doubt. 
Where neutral, and acid reaction is gained, the conditions 
will be found'to be quite different. In these cases the disease 
proper has passed over and gone, and instead of an eczema we 
have as a rule chronic proliferating dermatitis, perichondritis, 
etc., which seldom perfectly respond to treatment. 
Regarding the treatment of aural eczema, as it occurs in 
practice, I can only say the simplest treatment only is necessary, 
if the selection and methods be judiciously made and carried 
out. 
Cleansing, disinfection, and free access of air are the three 
all-important essentials upon which to base our treatment, but 
the mode of cleansing and the agents to use, as well as their 
mode of application, are exceedingly important points in the 
successful handling of these cases. 
The cleansing of the ears should, from beginning to end, be 
with sterilized absorbent cotton applied with the ear forceps and 
not one drop of water should be used. 
The disinfectant should be one of the most powerful, and be, 
at the same time, selected with most careful respect to its special 
adaptations in such cases, and be brought to all parts with 
equality and certainty. 
To accomplish this satisfactorily I at first make use of 
hydrarg. perchlor. and spts. vini. rect. in the strength of one to 
one thousand. This solution I reduce one-half in strength im¬ 
mediately the condition begins to yield to treatment. 
I have found this spirit of sublimate to far exceed all other 
sterilizing fluids, and attribute its qualities, first, to the high 
