H4. ON THE STABLE, 



frequently none whatever. The vigorous and 

 full enjoyment of animal faculties, depends con- 

 siderably on their being sufficiently exercised ; 

 hence the stimulus of light is necessary to 

 strengthen the eye, and to render it capable of 

 perfect vision. But when the animal is shut up 

 hi an obscure situation, probably during the 

 greatest part of the day, it must necessarily fol- 

 low that the function of sight will be propor- 

 tionably impaired, which is manifest by his 

 winking his eyelids, from being unable to bear 

 a sudden increase of light on being led out of 

 the stable. It is usual to lessen the darkness 

 of stables by whitewashing the walls ; but this 

 intention would be better efl'ected by enlarging 

 the windows. The influence of light upon ve- 

 getable and animal bodies has been ascertained 

 by experiment, and it appears that, when de- 

 prived of it, they are neither so perfect in their 

 colours, nor so vigorous in their constitutions. 

 Birds of the northern regions are not so brilliant 

 in their plumage as those of the south. It is 



also 



