BIRDS. 243 



sequently it can neither swim nor dive, and is seldom 

 seen at any very considerable distance from land ; al- 

 though its lightness of frame and extraordinary power 

 of wing enable it to hover over the ocean with un- 

 wearied assiduity. Neither does it alight on the rig- 

 ging of ships, like many other amphibious species, as 

 terns and boobies. It is true, that when on the Equator, 

 in long. 137 E., we captured one example, which 

 alighted on the spanker- gaff and permitted itself to be 

 taken by hand ; but this was regarded by our crew as 

 an unprecedented occurrence, and as the individual, 

 although of adult size, was evidently young, youthful 

 indiscretion was pleaded as its excuse. 



Sailors believe that the sea-hawk sleeps on the wing ; 

 though I am not aware that there are any recorded 

 facts in favour of this notion. When the nearest land 

 is remote, they will continue fishing around a ship for 

 many successive days and nights, and continue un- 

 remittedly on the wing ; but when in the immediate 

 vicinity of land, they invariably return to the shore at 

 sunset. Their flight is exceedingly easy and graceful, 

 and has also the charm of variety : sometimes the bird 

 may be seen balanced in mid-air, its wings spread but 

 apparently motionless, its long forked tail expanding 

 and closing with a quick alternate action, and its head 

 turned inquisitively from side to side to inspect the 

 ocean beneath ; sometimes it wheels rapidly, or darts 

 to the surface of the water in pursuit of prey ; and at 

 others, soars to so great a height that it is lost to vision, 

 or becomes a mere speck in the sky an elevation of 

 flight which is alone sufficient to distinguish this from 

 all other sea-birds. 



They apparently take a delight in soaring over the 

 mast-head of a ship, from which they usually tear 



R 2 



