PELICANS, CORMORANTS, AND PETRELS. 265 



is difficult to understand, for they scarcely ever flap their wings, but 

 sail gracefully along, swaying from side to side, sometimes skimming 

 the water so closely that the point of one wing dips into it, then 

 rising up like a boomerang into the air, then descending again, and 

 flying with the wind or against it, apparently with equal facility. 

 Now and then, but seldom, they give two rapid flaps with their 

 wings, but to see this they must be watched." 



Dr. Moseley says, in regard to their flight, 



" I believe that Albatrosses move their wings much oftener than is 

 suspected. They often have the appearance of soaring for long 

 periods after a ship without flapping their wings at all, but if they be 

 very closely watched, very short but extremely quick motions of the 

 wings may be detected. The appearance is rather as if the body of 

 the bird dropped a very short distance and rose again. The move- 

 ments cannot be seen at all unless the bird is exactly on a level with 

 the eye. A very quick stroke, carried even through a very short arc, 

 can of course supply a large store of fresh momentum. In perfectly 

 calm weather Albatrosses flap heavily." 



