76 ORGANS OF VOICE. 



one of our shyest and most timid birds, will fre- 

 quently discover its nest, by making a jarring noise, 

 and also a snapping and cracking, at the same time 

 pursuing people along the hedges, as they walk, 

 when its young are in a helpless state. The male 

 Blackcap is still more incautious, for it will com- 

 mence and continue its song, even when sitting on 

 its nest, and thus too frequently become the innocent 

 cause of the capture of its brood. 



The loud cries of other birds, however, particu- 

 larly of many of the migratory water-birds, which 

 fly J3y night, are evidently intended for the purpose 

 of keeping them together. Few have been without 

 opportunities of listening, in the silence of the night, 

 to the incessant cackling of a flight of wild Geese, 

 on their way to some distant spot, high in the air. 

 In the northern seas, sounds of this sort are more 

 frequently heard, from birds which never come so 

 far to the southward. Of these is the red-breasted 

 Diver, which seldom quits the water by day, but 

 during the night may be known to be on the wing, 

 at a vast height, by a peculiarly melancholy and dis- 

 tressing scream, exactly resembling that of a young 

 child suffering from agonizing pain. We have 

 listened, by the hour together, to the repeated and 

 successive waitings of these wild melancholy birds; 

 first, the scream is faint, and so distant as scarcely to 

 reach the ear; then increases as the bird passes 

 nearer, till, as it continues its flight, the sound gra- 

 dually dies away. Soon, another scream from another 

 quarter is faintly heard ; and so on, till the dawn 

 appears, when they betake themselves to the element 

 on which they pass the day. 



