250 THE HAUNTS OF LIFE 



of the body, to one side or the other, bending 

 and straightening, may be very effective 

 although there is no actual movement of the 

 legs. Experienced mountain-climbers are also 

 aware of the importance of slight adjustments 

 which are eventually made almost without 

 thinking. In any case we are probably safe in 

 saying that the sailing albatross is not behav- 

 ing like a kite. 



MIGRATION THE CLIMAX 



The crowning advantage of the power of 

 flight in birds was that it enabled them to 

 migrate, to evade the difficulties of the winter. 

 In north temperate countries the great majority 

 of the birds show this seasonal mass-movement 

 between a nesting-place and a resting-place, 

 the former being always in the colder part of 

 the range. It is remarkable in many ways, this 

 migration of birds (see our Wonder of Life 

 (1914) and Biology of the Seasons ( 1 9 1 1 )) ; it 

 occurs in such a punctual, orderly way ; it is 

 such an intense activity, for many migrants seem 

 to keep up for hours on end a speed of a mile 

 a minute ; it means such an annihilation of 

 distance, for the Pacific Golden Plovers of 



