4 A PHILOSOPHER WITH NATURE 



age, but you notice as you look through a glass 

 that the greater majority of the others have im- 

 mature markings ; for it is the breeding time and 

 only these young birds of the previous year have 

 this leisure. The older birds are all at the nesting 

 haunts on the cliffs beneath the horizon. 



At the line of the water's edge many different 

 kinds of sea-fowl are congregated. The great shel- 

 ducks which have followed the tide outwards stand 

 in groups upon the higher mounds of mud, preening 

 themselves in the morning sun after their meal, the 

 pure black and white plumage showing strangely 

 conspicuous against the grey background. The 

 little merry dunlins are wading knee-deep in the 

 water or racing on the mud ; oyster catchers, feeling 

 less at home here than on their native rocks, stand 

 apart from the others ; and mallards and shelducks 

 rise and fall with the swell in the shallow water. 

 Some of the latter are standing inland, resting on 

 one leg and with beak thrust into the back feathers, 

 but with eyes open, a picture of repose and alertness. 

 Now a flight of ring-dotterel skims low over the 

 water, the mass of birds swerving and curving as if 

 it were directed by a single will, the white of the 

 under-plumage flashing suddenly in the sun and 

 being as instantly occulted. It is a sight which 

 when the flocks of birds number thousands sends a 

 ripple down the back as if one watched the evolu- 

 tions of an army rendering instant obedience to a 

 signal from the mind of a commander. Yet observ- 

 ing the movement now, it may be seen how the effect 

 is produced. The passing impulse which gives rise 

 to the sudden change of flight is often capricious and 

 confined to few of the birds. But the rapidity of the 



