112 NATURAL HISTORY 



there all night. As soon as the air became 

 clear and pleasant they all were on the 

 wing at once ; and, by a placid and easy 

 flight, proceeded on southward towards the 

 sea : after this I did not see any more flocks, 

 only now and then a straggler. 



I cannot agree with those persons that 

 assert that the swallow kind disappear some 

 and some gradually, as they come, for the 

 bulk of them seem to withdraw at once : 

 only some stragglers stay behind a long 

 while, and do never, there is the greatest 

 reason to believe, leave this island. Swal- 

 lows seem to lay themselves up, and to 

 come forth in a warm day, as bats do con- 

 tinually of a warm evening, after they have 

 disappeared for weeks. For a very respect- 

 able gentleman assured me that, as he was 

 walking with some friends under Mertow 

 wall on a remarkably hot noon, either in 

 the last week in December or the first week 

 in January, he espied three or four swallows 

 huddled together on the moulding of one 

 of the windows of that college. I have fre- 

 quently remarked that swallows are seen 



