NATURAL EQUILIBRISTS 83 



poise is only possible to these natural equili- 

 brists who have not to think about their 

 actions, but who are inspired by infallible 

 subconsciousness. Once a bird began to 

 consider distances and to calculate the effects 

 of gravitation, etc., Uke a human being, it 

 would have to learn by practice how to do 

 these things ; moreover, some would prove less 

 proficient than others, whereas we observe in 

 nature that birds on gaining their full powers 

 are, one and all, faultlessly perfect in their 

 manifestations, whatsoever. The slightest 

 failing means prompt extinction of the indi- 

 vidual. 



Woodpeckers are, perhaps, the best ex- 

 ponents of undulating flight. The green- 

 woodpecker (Picus viridis) is the largest 

 British bird to fly in this fashion, and can 

 always be identified by its flight independent- 

 ly of its brilliant plumage. One has only to 

 watch a bird of this species flying from tree to 

 tree, to see how admirably the flight serves to 

 bring it perpendicularly up against the bole 

 of the tree. In no other way could the bird 

 possibly arrive in such a position with the 

 same grace and precision. To fly directly up 

 against the tree would be a clumsy proceeding 

 and detrimental to head and wings ; but as it 

 is the wings are folded out of the way before 



