86 



STRUCTURE AND COMPARISON. 



Otliers say that the bird tiies like a kite, and this is pajtly 

 right. The bird's body does act very much like the string of 

 the kite, serving as a weight to hold it steady. But the kite 

 cannot lift the boy at the end of the string; if it could, the 

 kite would fall just as we see it do when the string breaks. 



That laughable story for boys, '' Phaeton Rogers," tells us 

 how Phaeton made his great kite draw his wagon down the 

 road, and how the kite ran away with him while the whole 

 town raced after to find out what the matter was. Now we 

 know that the kite would not fly at all unless it could keep 

 a taut string; and the faster the wagon moved the nearer it 

 would be to outrunning the kite, so that it is hardly probable 

 that Phaeton's wagon would travel as fast as the story says. 

 Did you never underrun your kite and bring it down even 



Fig. 18. Gulls Flvixu — Fkom Instantaneous Photograph. 



(After Marey.) 



(The dotted line shows successive positions of wrist joint in flight.) 



when there was a good breeze ? Now in most instances a 

 bird outruns the breeze, and he has no stationary weight; 

 for his body, the weight, travels as fast as the wings. So we 

 see that a bird does not resemble the kite. 



More nearly does the bird resemble the swimmer, who supports 

 himself in the water by striking out with his arms, pushing him- 

 self up and forward by the resistance of the water to his stroke. 

 The bird rises and moves ahead by the forward and downward 

 sweep of his wings, falls a little in air as he again raises them, 

 and once more moves ahead and up with the new stroke. 



