BIRDS. 



11 



low. The skin forms itself into a little bag, which is fed from 

 the body by a small vein and artery, and which every day in- 

 creases in size till it is protruded. While the one end vegetates 

 into the beard or vane of the feather, that part attached to the sk'n 

 IS still soft, and receives a constant supply of nourishment, which 

 is diffused through the body of the (luill by that little light sub- 

 stance which we always find within when we make a pen. Thi° 

 substance which as yet has received no name that I know of, 

 serves the growing quill as the umbilical artery does an infant in 

 the womb, by supplying it with nourishment, and diffusing that 

 nourishment over the whole frame. When, however, the quill 

 is come to its full growth, and requires no further nourishment, 

 the vein and artery become less and less, till at last the little 

 opening by which they communicated with the quill becomes 

 wholly obliterated ; and the quill, thus deprived, continues in 

 its socket for some months, till in the end it shrinks, and leaves 

 room for a repetition of the same process of nature as before. 



The moulting season commonly obtains from tlie end of sum- 

 mer to the middle of autumn. The bird continues to struggle 

 with this malady during the vvinter ; and nature has kindly pro- 

 vided, that when there are the fewest provisions, that then the 

 animal's appetite shall be least craving. At the beginnmg of 

 spring, when food begins again to be plentiful, the animal's 

 strength and vigoiu- return. It is then that the abundance of 

 provisions, aided by the mildness of the season, incite it to 

 love, and all nature seems teeming with life, and disposed to 

 continue it. 



CHAP. II. 



OF THE GENKRATION, NESTLING, AND INCUBATION, OF EIBD3. 



The return of spring is the beginning of pleasure. Those 

 vital spirits, which seem locked up during the winter, tlien be- 

 gin to expand; vegetables and insects supply abundance of 

 food; and the bird having more than a suilicieney for its own 

 subsisteiice, is impelled to transfuse lii'c, as well as to maintain 

 ir. Those warblings, which had been hushed during the colder 



