OPHTHALMIA. 95 



lids, and drawing a keen lancet slightly over them, is the most 

 effectual of all ways to ahate inflammation, for we are then im- 

 mediately miloadiug the distended vessels. He places his seton? 

 in the cheek, or his rowels imder the jaw; and he keeps the 

 animal low, and gives physic or fever medicine (digitalis, nitre 

 and emetic tartar). The disease, hoAvever, ebbs and flows, re 

 treats and attacks, until it reaches its natural termination, blind 

 iiess of one or both eyes. 



The horse is more subject to this disease from the age of foui 

 to six years. Every affection of the eye appearing about tliia 

 age, should be regarded with suspicion. The eye should be 

 most carefully observed at the time of purchase, and the ex- 

 aminer should be fully aware of the minute indications of dis- 

 ease. They are a slight thickening of the lids, or puckering tow- 

 ards the, inner comer of the eye ; a difference in the apparent 

 size of the eyes ; a cloudiness, although perhaps scarcely per- 

 ceptible, of the surface of the cornea, or more deeply seated, 

 or a hazy circle round its edge ; a gloominess of eye generally, 

 and dulness of the iris ; or a minute, faint, dusky spot in the 

 centre, with or without minute fibres or lines diverging from it. 



There is undoubtedly a strong predisposition to this inflamma 

 tion in the eye of the horse, but it is assisted by the heated and 

 empoisoned air of many stables. The dung and urine of the 

 horse, and the litter when becoming putrid, emit fumes of vola- 

 tile alkali, or hartshorn. We need not wonder at the prevalence 

 of inflammation m the eye of the stable horse, nor at the diffi- 

 culty in abating it, while this organ contmues much exposed to 

 the effect of this pungent gas. 



Dark stables are another cause of ophthalmia. Let the horse 

 be led several times a day from a dark room into a full glare 

 of light, and the sight will become disordered, the eyes weak, 

 and disposed to take on sudden inflammation, with all its fatal 

 results. 



The disease is also in a high degree hereditary. A stallion with 

 defective sight should never be employed. 



The most frequent consequences of this disease are cloudiness 

 of the eye, and cataract. The cloudiness is singular in its nature. 

 It will change in twenty-four hours from the thinnest film to the 

 thickest opacity, and, as suddenly, the eye Avill nearly regain its 

 perfect transparency, but only to lose it, and as rapidly, a second 

 time. 



Chalk, salt, sugar, and even pounded glass have been intro- 

 duced into the eye to remove the film, but we need not say that 

 the effect of such remedies would be to recall the inflammation, 

 and that they are utterly barbarous. Where the cloudiness can 

 bo removed, it will be best effected by first abating inflamma 



