CHAPTER II. 



THE MATERIALS. 



THE instinct with which the Creator has 

 endowed birds, in the construction of their nests, 

 is not less manifest in the choice of the materials 

 of their fabric, than in that of the situation in 

 which it is placed. The end in view namely, 

 the preparation of a suitable cradle for the young, 

 and a commodious structure for the parent in 

 the act of incubation, or hatching is variously 

 attained, but is always attained, although the 

 materials of the nest differ from each other as 

 widely as possible. In some cases, it appears 

 necessary that the young should be defended from 

 the penetrating blasts of the chilly days of spring ; 

 and this is done by the employment of a material 

 which is as impervious to air as are the walls of a 

 cottage. This is eminently the case in the nest of 

 the song-thrush, which has a mud lining within, 

 surrounded by vegetable materials of various kinds 



