252 Union Bay 



searched busily for insects over the water. Where had they 

 gone? 



I could have answered the question without difficulty had 

 I been a Greek follower of Aristotle. Observers in the Middle 

 Ages would have had a ready explanation. I could have got- 

 ten the same ready answer from the country folk and even 

 from the scientists of a couple of hundred years ago. All 

 would have said that, summer being over, the birds had hid- 

 den themselves in dark caves or crevices where they would 

 remain until spring, or they had buried themselves in the soft 

 mud of the marsh where anybody who knew how to find 

 them could dig them out. If I had been incredulous, many 

 reputable witnesses could have been produced who had seen 

 them in the veiy act of submerging: they had crowded a bul- 

 rush to such an extent that the stalk yielded slowly and 

 gracefully to the strain and the whole mass approached the 

 water steadily. I had seen this performance many times in 

 the fall; how could I doubt the veracity of the witnesses? Of 

 course I had never seen the birds actually submerge. In fact, 

 I thought them young birds which wanted to flock together 

 and which had shown bad judgment in overloading their 

 perches. They had always flown away just at the moment of 

 immersion. Perhaps it was only my misfortune or lack of per- 

 sistence which had prevented me from seeing the actual 

 entry into the water on their way to the soft security of the 

 marsh bottom. The arguments against me would have been 

 heavy if I had tried to deny the hibernation. Did not the 

 birds congregate in large numbers and then disappear prac- 

 tically over night? Had anybody seen them afterward? They 

 could not get insect food in cold weather and they must seek 

 a winter hiding place. Did not mammals and fish hibernate? 

 Why should not birds? I could see little chance of winning 

 such an argument. 



I thought it strange that the belief in the hibernation of 

 swallows had persisted for so many centuries. For swallows 



