Migration of Swifts. 109 



expected to have had some influence in retarding their migra- 

 tion. That this was not the case was very evident; for, 

 although the month of August came in very hot, yet by the 

 9th they, apparently, had all taken their departure ; and for 

 several succeeding days I did not observe a single individual 

 of this species ; consequently, I was rather surprised on see- 

 ing a pair of these birds, on the morning of the 17th, winging 

 their rapid flight along the eaves of a house, where a colony 

 of those birds had taken up their residence, for the purpose of 

 nidification, during several seasons. I found, from observa- 

 tion, this pair of birds continued to frequent this locality for a 

 few days, when they disappeared. Their detention in this 

 country, I judged at the time, was owing to their having a 

 brood of young ones, which were unable to follow their con- 

 geners in the early part of the month. With this conjecture 

 I was obliged to rest satisfied, as I could not conveniently 

 ascertain the fact at the time. After an interval of a week, a 

 solitary individual made its appearance on the 28th, about 

 noon, the thermometer at the time standing at 60°. After 

 coursing round the same situation a few times, it disappeared ; 

 and none were seen afterwards. 



Although the summer of 1835 exceeded in heat that of the 

 preceding, yet, apparently, it had no visible effect whatever 

 upon the migratory movements of the swifts. Up to August 

 3., there appeared to be a daily increase to their numbers, as 

 they assembled, towards the evenings, in joyous conclaves, 

 high over the town. The severe drought experienced at that 

 time compelled the great majority of our Hirundines to seek 

 for food along the meadows adjoining the river; consequently, 

 but few were to be seen during the middle of the day. From 

 the 3d to the 18th, each assemblage gradually decreased in 

 numbers, when 1 only saw a few pairs, which, in a few days, 

 were reduced to a single pair; and they continued to resort 

 to their nesting-place throughout the month ; and, as they 

 still lingered in its vicinity, I was induced, on September 3., 

 to examine the situation ; when, to my utter astonishment, I 

 found a nest containing a pair of squabs, probably only a 

 week old. The parent birds were unremitting in their 

 exertions, throughout the remainder of the month, in bring- 

 ing food for their progeny ; apparently more so than at the 

 usual period of nidification, by their constant and repeated 

 visits during the middle of the day, which was evidently the 

 fact ; for, when I examined the nest again on October 1., I 

 found the pair of young birds very fat, and ready to wing 

 their flight to distant climes, which, I suspect, took place on 

 the 4th, that being the last day that I observed their parents 



