WAKING AND SLEEPING 5 



you look at their remote ancestry, you might 

 suppose that they would provide, at least, a sleeper 

 or two, for there seems little doubt that they are a 

 branch of the great reptile family, all the represen- 

 tatives of which in England are fast asleep at the 

 present time. 



Having wings they have little need to sleep 

 through the winter, and still less of the passive tem- 

 perament that makes such long oblivion possible. 

 When coldness and scarcity of food come, the bird, 

 except such steadfast souls as the robin, drifts with 

 the sun a little way southward, and there finds food 

 plentiful for another week. Thus it southerns 

 and southerns till the sea is reached, ancRhat, too, 

 it crosses if it has the hereditary instinct to face 

 a landless stretch that seems from the shore to 

 have no limit. The autumn migration of birds is 

 not our only evidence that Britain and Spain were 

 once joined with land. Ages ago, no doubt, a 

 southern lake across which the migratory bird 

 flew widened year by year till it became a strait, a 

 sea, an ocean, over which the birds still fly, because 

 their ancestors have done so every year for a 

 myriad generations. Any migrating animal would 

 have been stopped before the river had widened 

 to half a mile, unless we are to take it that the 

 strange whim that leads the hamsters to travel 

 across Norway in occasional swarms and throw 

 themselves into the sea is inherited from hamsters 

 of a million years ago th'at walked into Scotland 

 dry-foot by this route. 



