WIND AND FLIGHT 139 
seem to do, in open-mouthed astonishment. There 
is one question that, I believe, has been but little 
investigated. In tropical seas there may be up- 
currents rising from the heated surface, just as there 
are from sun-scorched plains even in much higher 
latitudes, up-currenis sufficient to serve the turn 
of the Albatross. But his evolutions are to be seen 
in Antipodean regions where no such heating is 
likely to take place. Myself I have little doubt that 
the Albatross’s art is only that of the Shearwater, 
though, owing to the great artist’s enormous spread 
of wing, the effect produced is much grander. A 
writer quoted in Flight (Feb. 3rd, 1912) describes 
it thus: “ The flight is generally near the water, 
often close to it. You lose sight of the bird as he 
disappears between the waves and catch him again 
as he rises over the crest. . . . He alters merely the 
angle at which his wings are inclined.”” Why, it is 
just in this style that a Shearwater sweeps down- 
ward, and then, by the help of a wave and the 
resultant up-current of air, regains all the altitude 
he has lost ! 
Advance Sideways in a Direct Line. 
To return to the Gull, a more commonplace, yet 
intensely interesting subject. Often, when he wishes 
to advance at right angles to the wind, he faces it 
and travels with motionless wings sideways, or, 
more correctly, almost sideways. As if thinking of 
his objective, he inclines head and body very slightly 
towards it. We are, of course, presupposing an 
upward-trending wind; the Gull is poised upon it. 
If the left wing leads, then the wind must be blowing 
