550 On Migration. 



prehensible act reaches its climax when we consider that some 

 (the young Cuckoos for example) have to make the long journey 

 alone and for the first time, with no parents to show them the 

 way, for they have long ago departed; and yet the young 

 Cuckoos, too, somehow make out the route to be taken, and these, 

 too, arrive at their destination in due course. 



To return again to the vicissitudes of weather which they must 

 encounter, on which I have briefly touched. Think of tho 

 furious gales, the torrents of rain, the pelting hail, the scorching 

 suns, they must at various periods of their travel meet with : how 

 can such frail bodies, supported by such tiny wings, endure such 

 tremendous assaults of the elements, and survive amid such 

 difficulties and dangers ? I make but small account of the 

 excessive cold to which in their passage they must often be ex- 

 posed, because I conceive that most birds are capable of enduring 

 a very low temperature without inconvenience. And I am not 

 disposed to make too much of rain-storms, because I have a 

 notion that most birds on migration ascend to a great altitude, 

 above the clouds, where they probably meet with currents of air 

 which waft them in the required direction. But even if we allow 

 them these advantages, they have difficulties enough to contend 

 against. That many species keep together in the flock in which 

 they started, and do not lose one another on the darkest of nights, 

 by means of the perpetual clamour they keep up, is certain, for 

 the cry of a migrating host may be often heard as it passes over- 

 head ; and it is not improbable that the smaller species in like 

 manner communicate to one another their mutual positions by 

 twitterings and call-notes peculiar to themselves. 



But, however successful their passage, that they are generally 

 exhausted when they reach the land, and drop down to rest in 

 the nearest available cover, is well known to all who are favourably 

 situated for observing them, on our eastern and southern coasts 

 more especially. The Quail which I mentioned above* as having 

 dropped down in my garden at Mentone, after a passage over the 

 Mediterranean from Africa, and suffered itself to be taken up in 



* Supra, p. 336. 



