34 ON THE EYE. 



anatomical name for this membrane is Membra- 

 na Nictitans ; but, perhaps, it will be more rea- 

 dily understood under the appellation of Hawes. 

 Farriers are so universally ignorant of the use of 

 this membrane, that they consider it as a disease, 

 and under that idea remove it by excision. The 

 pernicious consequences of this practice will be 

 explained hereafter. 



These are the principal points in which the 

 eye of the horse differs from that of the human 

 being : a more minute and technical explana- 

 tion would be, perhaps, both uninteresting and 

 unintelligible to the majority of my readers. 



The external surface of the eye, in its 

 healthy state, is thoroughly transparent. 



The center of it, which is denominated the 

 pupil, is generally of a dark indefinite colour. 

 The pupil has the property of contracting or di- 

 lating itself, in proportion to the strength of 



light 



