THE MYSTER Y OF MIGRATION 201 



lighthouse, nets in hand, to capture the birds which 

 strayed from the main body : 



'The whole zone of light within range of the 

 mirrors was alive with birds coming and going. 

 Nothing else was visible in the darkness of the 

 night but the lantern of the lighthouse vignetted 

 in a drifting sea of birds. From the darkness in 

 the east, clouds of birds were continually emerging 

 in an uninterrupted stream ; a few swerved from 

 their course, fluttered for a moment as if dazed 

 by the light, and then vanished with the rest in 

 the western gloom. Occasionally one wheeled 

 round the lighthouse and then passed on, and 

 occasionally one fluttered against the glass like a 

 moth against a lamp, tried to perch on the wire- 

 netting, and was caught by the lighthouse man. I 

 should be afraid to hazard a guess as to the 

 hundreds of thousands that must have passed in 

 a couple of hours ; but the stray birds which the 

 lighthouse man succeeded in securing amounted to 

 nearly three hundred. The scene from the balcony 

 of the lighthouse was equally interesting ; in every 

 direction the birds were flying like a swarm of 

 bees ! ' 



It remained for naturalists to find a probable 

 reason for the northern migration of birds, and to 

 explain the means by which, given the desire to 



