NATURALIST'S CABINET. 



Nature and arrangement of the plumage. 



of the earth; the latter soar up to the clouds: 

 all, however, are capable of varying their course 

 to every direction with the utmost promptitude; 

 and of descending from the greatest height, on 

 a particular spot, with equal safety and precision. 



Their bodies are clothed with feathers; which 

 are not only a defence against wet and cold, and 

 a means of hatching the young, but also most 

 convenient for flight. For these purposes they 

 are placed over each other, close to the body, 

 like the tiles of a house; and are arranged from 

 the fore-part backward, by which the animals are 

 enabled the more conveniently to cut their way 

 through the air. A short and extremely soft 

 down fills up all the 'vacant spaces between the 

 shafts of the feathers, in order to give a suitable 

 degree of warmth to the body ; and the w ing* 

 ;are so constructed, that in striking downward, 

 they expand very greatly ; and, except that they 

 are somewhat hollow on the under side, they be- 

 come, in this act almost two planes. The mus- 

 cles that move the wings dow r hwards have been 

 estimated, in some instances, to constitute not 

 less than the sixth, purl of the weight of the 

 whole body. 



The flying of the volatiles is thus effected. 

 The bird first springs with a violent Jeap from 

 the ground, stretcher his wings from the body, 

 and strikes them downwards with great force. 

 By this stroke they are put into an oblique direc- 

 tion, partly upwards and partly horizontally for- 



