The Senses 



209 



thousands of birds are annually hurled against these 

 objects to their destruction." 



A bird's eye is very large in proportion to the size of 

 its head, and is correspondingly perfect and delicate in its 

 workings. It rests in a deep cavity hollowed out of the 

 skull, and is protected by soft cushions of fat and controlled 

 by bands and pulleys of muscle which control its motions. 



Looking closely at the eye of a live bird, we at once 

 remark its brightness — that alertness of expression which 

 so truly reflects the virile life of these creatures. The 

 eye, more than any other part of a living organism, is 

 an index to the relative power of its intelligence — more 

 surely than all the other facial features taken together. 

 The eyes of a sloth are expressionless black spots, and 

 even those of an orang-utan are bleary and watery. 

 But a crow or magpie, or an}' other bird you may choose, 

 though with horny, shapeless lips, nose, and mouth, looks 

 at us through eyes so expressive, so human, that no won- 

 der man's love has gone out to feathered creatures through- 

 out all his life on the earth. A dog is a four-legged, hairy 

 animal with the eyes of a bird. 



The eye of a bird appears perfectly round, and is 

 composed of a central area of black, encircled by a ring, 

 sometimes hardly distinguishable from the inner divi- 

 sion, or again it may be highly coloured. The circular 

 centre or pupil is always of a uniform black, and no won- 

 der, for "it is not a thing — it is the hole in a thing." As 

 when we look through the lens of a camera, only the 

 blackened inside of the bellows is reflected to us, so in 

 the eye of a bird, the delicate living lens, itself invisible. 



