46 INTRODUCTION. 



coverings of Feathers. Of these there are three kinds,— 

 the Down, most abundant in the aqualio tribes, partieularly 

 the Duck, Goose, Eider Duck, ^c; — the small feathers, 

 which fall over each other like the tiles of a roof, and thus 

 conduct away the water; — and the quills; these last form 

 the wings and the tail, the largest of which, in the win<?-, 

 are called primary, and are ustially about eight or ten in 

 number; the smaller are termed secondary ; and the smallest, 

 by some naturalists, are called tertial. From the first kind, 

 the primaries, most of our writing pens are obtained ; and, it 

 may be mentioned, that these vary much in their sliape and 

 size, so that those conversant with the quills of Birds, ge- 

 nerally know and esteem the third quill for a writing pen as 

 the best ; it being one of the longest and largest. 



The feathers of birds are, in general, renewed annually ; 

 the process of renewal, termed moulting, takes place, it \& 

 said, generally during the autumn and winter; and, by the 

 return of spring it is completed, and the plumage looks 

 fresh and beautiful. It is also in some birds considerably 

 altered in colour at certain seasons, particularly that in 

 which the operation of procreation takes place; so that, 

 without an acquaintance with the fact, the birds would not 

 at such times be at all recognized as the same seen at 

 another season ; and, generally, it may be stated that the 

 plumage of all birds, in European climates at least, is most 

 vivid, intense, and striking, in the s|)ring, as if nature de- 

 signed that the season of love should be that in which health, 

 vigor, and beauty, may at once predominate. 



Some of the annually migratory birds, such as the Night- 

 ingale, Mr. Sweet informs me, moult twice in the year, 

 Uiimely, in spring and autumn: the reason for this would 

 seem to be, that as such birds take, most probably, long 

 flights, both at their coming and departure, their feathers 



