INTRODUCTORY. 9 



"Birds, the free tenants of land, and air, and 

 ocean," are such because of their marvelous powers 

 of flight. The heavy - winged heron in his lumber- 

 ing flight still surpasses the speed of the fleetest 

 race -horse. The wild duck covers ninety miles 

 in an hour, and the duck hawk 150 miles in the 

 same time. The graceful swallow, in its ceaseless 

 wanderings through the blue fields of the summer 

 sky, travels a thousand miles in a day. And the 

 endless flittings of the minor bird tribes from spray 

 to spray, or darting into the sunny air for their 

 jewelled prey, are ever marvels of grace, and free- 

 dom, and velocity of movements. You watch the 

 eagle, with scarce moving pinions, sweep for miles 

 and miles along the breezy coast, and, although 

 you cannot observe the movement, he exerts a 

 power sufficient to keep him from falling sixty-two 

 feet in a second. How tireless the exercise of 

 power put forth by the gull who wanders cease- 

 lessly for hours, and even days, over the restless 

 billow. The albatross and the frigate bird will 

 venture more than a thousand miles from land 

 in their foraying expeditions. 



It is this wonderful power of flight which makes 

 the Bird a migrant, changing its home with the 



