Ill 



THE ROWING FEATHER'S SECRET 



A STRAY feather cast by the random ring dove 

 gives us the principle of natural flight. There is 

 no mistaking it, and I never can understand how 

 Marey could dispute Pettigrew's view that bird and 

 insect alike flew themselves by screwing and 

 unscrewing their wings on the air. The screw 

 must be the master key that opens all the chambers 

 of the air to a bird, to a bat, to a bee. Perhaps 

 Marey missed this through knowing too much of 

 the details of flight. He overlooked the simple in 

 the subtle. 



The screw, as ruling principle of flight in Nature, 

 is not confined to animals. Even some plants are 

 fitted with it. I chanced to see a single samara, 

 or key, of the sycamore tree spinning down into the 

 road, and could not doubt that even here the 

 principle was at work, as in the grand wing action 

 of herring gull or falcon. 



The ring dove feather is the most constant 

 reminder of the principle. One can hardly walk a 

 mile in an English wood without seeing the feather 

 on the path. I picked up one in perfect condition ; 

 why such excellent feathers are shed I can hardly 

 say, unless it be that the bird often blunders so 



