384 STABLE MANUAL AND HORSE DOCTOR 



The edoje of the opening becomes ulcerous, and soon changet 

 to a true fistulous ulcer, the pipe itself, in old cases, 

 becoming as hard as cartilage. The digestion, too, becomes 

 deranged from the loss of that valuable secretion, the saliva, 

 which is squirted out through the fistula instead of being 

 conveyed, as when the duct is whole, into the mouth to be 

 mixed with the food, and conveyed from thence to the 

 stomach. The position and function of the parotid gland 

 have been already described. The fluid expelled is semi- 

 transparent, afterwards tinged with pus from the ulceration, 

 and occasionally coloured with thin blood. 



The Causes of fistula of the parotid duct are generally 

 accidental injury, or abscesses resulting from strangles ; 

 hay seeds, and particles of hard food entering the opening 

 of the duct during mastication have produced it. These, 

 afterwards swelling, obstruct the egress of the saliva, which 

 accumulates ; the confined secretion produces agony, inflam- 

 mation, and abscess, which nature relieves by bursting ; 

 the pent-up secretion pours forth, and fistula is established. 



Treatment — Mr. Go wing's treatment may be thus 

 described : A firm, agglutinating liquid is formed by 

 dissolving fpn-cotton in sulphuric ether, which is called 

 collodion. Upon applying this liquid to the surface of the 

 body, the vital warmth occasions the ether rapidly to 

 evaporate, leaving the cotton in an altered form, sticking 

 firmly to the part. 



Mr. Gowing first applied some mild caustic to the wound, 

 till the orifice presented the reddened appearance he desired 

 it should assume. He then places above the opening a 

 bulky pledget, sufficiently large to thoroughly close the 

 wound, and sufficiently solid to resist the solvent powers of 

 the saliva. A piece of cork, cut to the required shape, 

 answers the purpose admirably. Over this, to bind it to 

 the part he wished it should close, he passed some cotton 

 thread, the ends of which he fixed to the hair of either side 

 by a liberal allowance of the liquid we before alluded to. 

 This he repeated several times till the plug was held firmly 

 to the place by the cross bands of cotton. He repaired this 

 dressing from day to day as it was necessary, having the 

 horse's head tied up, and supporting the animal entirely by 

 fluids. After a few days had elapsed the horse was allowed 

 to lie down ; and a short time subsequently the bandage 

 was removed, when the orifice was eventually stopped. 



