32 HISTORY OF 



are stocked with birds of the aquatic kind in 

 much greater plenty than in Europe ; and these 

 are generally clothed with a warmer coat of fea- 

 thers, or they have large quantities of fat lying 

 underneath the skin, which serves to defend 

 them from the rigours of the climate. 



In all countries, however, birds are a more 

 long-lived class of animals than the quadrupeds 

 or insects of the same climate. The life of man 

 himself is but short when compared to what 

 some of them enjoy. It is said that swans have 

 been known to live three hundred years ; geese 

 are often seen to live fourscore ; while linnets, and 

 other little birds, though imprisoned in cages, 

 are often found to reach fourteen or fifteen. 

 How birds, whose age of perfection is much more 

 early than that of quadrupeds, should yet live 

 comparatively so much longer, is not easily to be 

 accounted for ; perhaps, as their bones are 

 slighter and more porous than those of quadru- 

 peds, there are fewer obstructions in the animal 

 machine ; and nature thus finding more room 

 for the operations of life, it is carried on to a 

 greater extent. 



All birds in general are less than quadrupeds ; 

 that is, the greatest of one class far surpass the 

 greatest of the other in magnitude. The ostrich, 

 which is the greatest of birds, bears no propor- 

 tion to the elephant ; and the smallest humming- 

 bird, which is the least of the class, is still far 

 more minute than the mouse. In these the ex- 

 tremities of nature are plainly discernible ; and in 

 forming them she appears to have been doubtful 



