ship, or in such favoured spots as are to be found about the 
bridges of London during the winter, careful watch will show 
that the legs are frequently used when efforts are being made 
to turn, or check the speed of flight. 
Some of the smaller petrels—like the storm-petrel, or 
‘“‘ Mother Carey’s chickens,” will patter over the water with 
their feet as they fly just over the surface of the waves. 
Whether the legs are carried drawn close up beneath the 
breast, or thrust backwards under the tail, the purpose of 
this disposal is the same—to prevent any interference with 
the “‘ stream-lines ”’ of the body which would impede flight. 
On the matter of the speed of flight there seems to 
be much misconception. Gdatke, the German ornithologist, 
gravely asserted that the little Arctic blue-throat—one of 
our rarer British birds—could leave its winter resort in 
Africa in the dusk of evening, and arrive at Heligoland— 
where he spent so many years studying bird migration— 
nine hours later. That is to say, it could travel 1600 geo- 
graphical miles in a single night, at the astounding velocity 
of 180 miles an hour! According to another estimate of 
his, curlews, godwits, and plovers crossed from Heligoland 
to the oyster-beds lying to the eastward, a known distance of 
rather more than four English miles, in one minute; or at 
the rate of over 240 miles an hour. Against such extravagant 
estimates it is hardly necessary to bring rebutting evidence, 
179 
