GLASS EYES. 163 



GLASS EYES. 



This diseased state of the eyes is technically termed 

 amaurosis, and consists of loss of sight from diseased 

 condition of the optic nerve and retina. The eye, to all 

 appearance save the imperfect functions of the retina, 

 is healthy and sound. It may be caused by increased 

 or diminished sensibility of the retina. This disease 

 very rarely attacks both eyes at the same time. It is 

 said to be the frequent consequence of staggers and 

 immoderate bleeding. It may be discovered by the 

 timidity and uncertainty of the horse's action, by the 

 fixed size of the pupil, a shrunken iris, and insensi- 

 bility to the light of a candle if placed close and op- 

 posite to the eye in a darkened stable. 



The cause of this disease is irritability of the retina, 

 consequent on a determination of blood to the head in 

 some cases, and in others is the result of ophthalmia. 

 I had a horse in my possession affected with this disease 

 from the latter cause, which took place while riding 

 to meet a pack of fox-hounds only six miles distant, so 

 rapid is its progress at times. I first discovered it 

 by his continually putting one or other of his feet into 

 the grips and gutters alongside of the road, a thing 

 that I never knew him do previously. He then went 

 much as usual, until arriving at a water ditch, into the 

 middle of which he went without an effort to save him- 

 self, and, on coming to the stable, he walked straight 

 up against the wall, being evidently unaware of its 



M 2 



