104 DARWINISM AND THE PROBLEMS OF LIFE 



the perfect silence of Nature, and the consciousness 

 of the nearness of the vast sea, awoke a feeling of 

 sublimity in the soul of the observer. Then the cry 

 of a bird broke the stillness, then a second, and the 

 noise grew louder and louder, until at last countless 

 flocks of birds of all kinds shone like sparks in the 

 beams of the light - house, circling round it like a 

 snow-storm, and then disappearing in the impenetrable 

 darkness. Larks, starlings, plovers, snipes, and many 

 other species were recognised by him. At one time 

 an owl appeared, and then passed with loud flap of 

 wings into the darkness, accompanied by the plaintive 

 cry of a thrush that had been caught in the general 

 turmoil. 



When the moon and the stars shone, the sight was 

 less splendid, as the birds then flew higher, and were 

 not caught in the light of the lantern. It seems, then, 

 from Gatke's observations, that the migration does 

 not take place at a great height, at least on cloudy 

 nights ; and this has been confirmed by recent 

 observations. 1 



Aeronauts have let loose various birds from balloons, 

 and it was found that in clear weather the birds went 

 straight downwards. But if the balloon was above 

 a thick stratum of cloud, the birds were puzzled and 

 flew hither and thither, and settled on the balloon 

 again ; though they immediately left it when it fell 

 below the clouds and the earth could be seen. They 

 then made for the ground. The same thing happened 

 if there was a break in the clouds through which the 

 1 Gatke himself held to the theory that the birds fly high. 



