DISEASES OF THE FACIAL SINUSES. 523 



It is especially requisite to vary the tonics. Give the follow- 

 ing for one week : — 



Cupri Snip. 5ii., 



Canth. pulv. gr. v., m., fiat bolus, 

 and administer twice a day after a full meal. The ball may be 

 continued if the case seems to improve, but should it be thought 

 that amendment has discontinued, the salt of iron is to be 

 substituted for the copper. A very favourite medicine of mine 

 is the colchicum powder, in addition to the tonics ; it acts un- 

 mistakeably on the kidneys, and encourages the excretion of the 

 effete hippurates and other urinary salts. Eegular exercise, in 

 addition to the grooming, should be insisted upon, and it is 

 good practice to order the food to be placed near the ground, 

 as movement of the jaws and a depending position of the head 

 favour the discharge of the imprisoned matters. 



There are many diseases of the sinuses that result in no per- 

 manent improvement after operation and treatment. Upon this 

 ])oint the observations of Professor Yarnell are most valuable. 

 He says, in the Veterinarian for May 1867, " Diseases of the 

 sinuses of the facial region of the horse's head, arising, as pre- 

 viously stated, from external violence, are seldom treated suc- 

 cessfully, therefore it is not often that a radical cure is effected. 

 Generally speaking, the disease advances comparatively quickly, 

 or it may be, on the other hand, it progresses very slowly, 

 which will depend upon the age and constitution of the horse, 

 and the pathological nature of the malady. It is seldom, 

 however, that he is allowed to die from the effects of the 

 disease itself, humanity, if not economy, suggesting the advisa- 

 bility of having him destroyed. 



"The osseous boundaries of the sinuses, together with the 

 membraneous covering, the inner one in particular, become 

 thickened from being infiltrated with inflammatory exudation, 

 the blood-vessels and Haversian canals enlarge, the bone softens, 

 and its cancelli become filled with a semi-gelatinous or oily 

 material, the thickening of the membrane gradually increases, 

 its surface becomes uneven, and when its structure is examined 

 it will be found to have somewhat of a greasv character. From 

 these causes the sinuses, which gradually become diminished in 

 capacity, will, in the process of time, also become partly or 



