SWAN OF CURRITUCK SOUND 159 



surprising as their speed, for they are said to travel 

 a thousand miles without alighting. 



When making these long journeys they fly high, 

 so high indeed that they are often invisible to the 

 naked eye. Yet on a still night you can distinctly 

 hear the rhythmical singing noise of the long wings 

 striking the air with force sufficient to drive the 

 huge birds at a speed greater than that of the 

 fastest express train. 



The flocks are usually led by an old and ex- 

 perienced swan, and it is said that as one becomes 

 tired of leading, or it _ might be called aerial trail- 

 breaking, his place is taken by another whose 

 strength is equal to the task, and so they continue 

 until they reach their destination, the southern 

 feeding grounds of the winter or the northern 

 breeding places of the summer. Occasionally they 

 stop to rest in the region of the Great Lakes. 

 Not many years ago, while on their way north, a 

 large number stopped above Niagara Falls, and 

 more than a hundred were, by some extraordinary 

 mischance, carried over the falls and killed in the 

 surging waters. 



Whether the swans prepare in any special way 

 for their southward journey is not known, but 

 before starting north they indulge in the curious 

 habit known as " ballasting " that is to say, they 

 eat great quantities of sand, for what purpose no 

 one knows. 



In the far away Arctic Ocean is their breeding 

 place, and it is believed that they mate for life. 

 Their nests, which are placed on the ground, are 

 of immense size, fully six feet long and two feet 



