SPECIFIC OPHTHALMIA. 165 



They are a slight thickening of the lids, or puckering towards the inner corner 

 of the eye ; a difference in the apparent size of the eyes ; a cloudiness, although 

 perhaps scarcely perceptible, 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. 



The cause of this inflammation is undoubtedly a strong predisposition to it in 

 the eye of the horse, but assisted by the heated and empoisoned air of many 

 stables. The heated air has much to do with the production of the disease ; 

 the empoisoned aira great deal more: for every one must have observed, on entering 

 a close stable early in the morning, strong fumes of hartshorn which were pain- 

 ful to his eyes and caused the tears to flow. What must be the constant action 

 of this on the eyes of the horse ? The dung of the horse, and the litter of the 

 stables, when becoming putrid, emit fumes of volatile alkali or hartshorn. Often, 

 very soon after they are voided, they begin to yield an immense quantity of this 

 pungent gas. If we are scarcely able to bear this when we stand in the stable for 

 only a few minutes, we need not wonder at the prevalence of inflammation in 

 the eye of the stabled horse, nor at the difficulty of abating inflammation while 

 this organ continues to be exposed to such painful excitement. Stables arc now 

 much better ventilated than they used to be, and ophthalmia is far from being so 

 prevalent as it was fifty years ago. 



The farmer may not be aware of another cause of blindness, to which his 

 horse is more particularly exposed, viz.,. confinement in a dark stable. Many 

 stables in the country have no glazed windows, but there is a flap which is open 

 for a few hours in the day, or while the carter is employed in the stable, and 

 when that is shut down almost total darkness prevails. Let our reader consider 

 what are his sensations when he suddenly emerges from a dark room into the 

 full glare of light. He is dazzled and bewildered, and some time passes before 

 his vision is distinct. Let this be repeated several times daily, and what will 

 be the consequence ? The sight will be disordered, or the eye irreparably in- 

 jured. Then let him think of his poor horse, who often stumbles and starts 

 through no fault of his own, although he is corrected for his blundering, but 

 because his eyes are necessarily weakened by these sudden transitions, and dis- 

 posed to take on sudden inflammation with all its fatal results. 



The propagation of various diseases, and this more than any other, from the 

 sire to his progeny, has not been sufficiently considered by breeders. Let a stal- 

 lion that is blind, or whose sight is defective, possess every other point and 

 quality that can be wished, yet he is worse than useless for a very considerable 

 proportion of his offspring will most assuredly inherit weak eyes or become 

 totally blind. There is no fact better established than this. 



Mr. Baker of Reigate puts this in a very strong point of view. He was called 

 upon to examine a foal only a few days old, which seemed to have some affection 

 of the head, as from its birth it was totally unconscious of any object, although it 

 appeared to the owner to have good eyes. It ran its head against the wall and 

 the standers by, in such a way as to convince the surgeon that it was quite blind, 

 and on examining the pupil of each eye, he found them greatly dilated and mo- 

 tionless, but beyond this there was no unhealthy appearance. 



He inquired about the sire, and found that his vision was very defective, 

 and that of all the stock which he got in that part of the country, not one colt 

 escaped the direful effects of his imperfect sight. He persuaded the owner to 

 have the youngster destroyed, and in tracing the optic nerve in its passage from 

 the base of the brain, he found it in a complete state of atrophy. There was 

 scarcely any nervous substance within the tube that led from the brain to the 

 eye. 



