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,— 
“‘T 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.” 
