DISEASES OF THE EAR. 299 



When the disease is chronic, astringent lotions, allied 

 to those already advised for various forms of inflamma- 

 tion, are applicable. Tannic acid, borax, boric acid, zinc 

 sulphate, etc., are all of value, and if some glycerin be used 

 in their solution with water, they are more effectual, as 

 they do not evaporate so soon. 



The following may serve as an example : 



B Acid carbolic 3 ss. ; 



Zinci sulph 3 j 



Sod. biborat 3 j ; 



Glycerin ij ; 



Aquae ad J vj. 



Ft. mist. 



Sig. : Pour in or inject a teaspoonf ul, warm, two to 

 three times a day after cleansing with warm water. 



The lotion recommended for ophthalmia, etc. (p. 309), 

 is also valuable. In chronic cases tincture of iodine may 

 do good. When there is much smell, iodoform blown in 

 is invaluable. Medicated oils serve a good purpose. 



If the discharge is profuse and the affection of long 

 standing, astringent powders blown in will be more effect- 

 ive sometimes than liquid applications. Some of the best 

 of these have been mentioned for lotions, and to the list 

 may be added dry oxide of zinc and alum, or these mixed 

 with subnitrate of bismuth to render them less powerful. 

 For the parasitic form of the disease mercurial ointments 

 are the most efficient. The yellow oxide of mercury, one 

 grain to one drachm of vaseline, applied daily, often cures. 



In nearly all cases the general health of the dog will 

 require attention. The bowels should be relaxed, though 



purging is not called for. The alimentary canal is often 

 21 



