DR KNOX on the Comparative Anatomy of the Eye. 55 



jects placed at a vast distance is tolerably distinct. It is strong 

 in man, and in the quadrumana ; weak in the ox and sheep, but 

 still weaker in the horse ; very powerful in the deer tribe, and 

 no doubt in the antelope. I had often remarked, without being 

 able to assign a reason, how greatly the antelope and deer trust- 

 ed to the organ of vision, and how inferior their organs of smell 

 were to those of the horse and ox. Whoever will carefully at- 

 tend to the habits of these animals when allowed to roam about 

 at large, may observe, that the horse and ox fearlessly enter 

 thickets, trusting to the acuteness of their smell for the disco- 

 very of wild ferocious animals, whilst the antelope prefers the 

 open plains, and seldom resorts to the bushy country, unless ur- 

 ged to it by a want of herbage and water *. Horned cattle, 

 with most ruminating animals, graze generally towards the quar- 

 ter whence the wind blows ; and, though I am aware that other 



* I observed a very singular fact in Africa, which first awakened my suspicions 

 relative to the defective vision of the horse. In that country we were forced, from a 

 deficiency of pasturage, to allow our horses to graze at perfect liberty on the open de- 

 serts, and they, so situated, seemed to acquire many of the habits which the animal would 

 probably possess in a perfectly wild state. They grazed generally in small troops, to 

 which an entire horse, or one of the boldest of the geldings, seemed to serve as pro- 

 tector ; on the approach of strangers, the troop immediately collected into a circle, and 

 remained so until the horse appointed to watch over the general safety had ascertain- 

 ed whether or not danger was to be apprehended, by a nearer approach of the object 

 suspected. On one occasion, having gone into the fields with a few friends, of whom 

 one was dressed in a morning gown, and, coming unexpectedly on the troop of horses, 

 they were observed to collect immediately into a circle, and to detach one of their 

 number, with a view to ascertain the nature of the very unusual appearance, which 

 they evidently saw but indistinctly, though scarcely three quarters of a mile removed 

 from the place we stood. It was now I remarked, with some surprise, that the horse did 

 not, during the very long and circuitous course, approach much nearer to us, but made 

 hastily for that situation in which we should be placed between him and the quarter 

 from whence the wind blew ; thus evidently employing the organ of smell in prefe- 

 rence to that of sight. 



