62 NATURAL HISTORY 



And I myself, on the twenty-ninth of last October (as 

 I was travelling through Oxford), saw four or five 

 swallows hovering round and settling on the roof of the 

 county hospital. 



Now is it likely 10 that these poor little birds (which 



It was wet, cold, and foggy, witlj only occasional gleams of sunshine : 

 but in spite of the weather these birds continued to fulfil their parental 

 functions with the most persevering assiduity and industry. Taking 

 advantage of every propitious hour to prepare their young for their 

 distant journey, and as if instinctively aware of the necessity of expe- 

 diting their departure, they subsequently appeared to have brought them 

 out earlier than usual, and seemed to be teaching them to fly. They 

 were observed to pass under the young bird when it appeared to be 

 sinking, and were seen to raise its head, assisting it thus in its progres- 

 sion through the air. I saw them on the 23rd of October ; and on the 

 24th they had departed. On the 28th martins were observed at Maida 

 Hill, Paddington : these had possibly been beaten back by the violent 

 storm from the south which occurred on the night of the 25th. G. D. 



10 It is, however, quite certain that young swifts, the moment they leave 

 the nest, have often occasion to make the great migration. See Mr. 

 White's Observation, Letter LI I. to Daines Barrington. The various 

 species of Himndines remain in their nests till they are more completely 

 feathered than other birds, and when they come forth they are matured 

 for flight. I suspect that the troublesome insect, called Hippobosca Hintn- 

 ilinis, is a resource in the scheme of providence, to force them to venture 

 upon the wing from the perilous height at which their nest is placed, by 

 making the abode insupportable. 



Few subjects are more interesting or more difficult to unravel, than the 

 instinct of birds. Instinct is explained by Dr. Johnson, to be desire or 

 aversion acting in the mind without the intervention of reason ; the power 

 of determining the will of brutes. He should have added in some parti- 

 cular cases, for it is not true generally. The will of brutes on many, and 

 indeed on most occasions, is influenced by memory of the past, and appre- 

 hension of the future, as much as that of a human being; and that which 

 is called reason in mankind is, perhaps, rather an improved state of 

 understanding, resulting from mutual communication of ideas through 

 the gift of speech, than a distinct and separate quality. Instinct is, in 

 fact, the immediate agency of the Almighty power on the mind of creatures 

 not endued with speech, which supplies the place of reason, and deter- 

 mines their most important actions : and perhaps in nothing is the uni- 

 versal superintendence of the Almighty more wonderfully displayed, 

 than in its immediate agency upon the minds of the most insignificant 

 creatures. 



The difficulty attending this subject is, to distinguish imitation of the 

 parents, from instinctive propensities. It is well known to those who 

 teach young birds to pipe, or rear them to learn the notes of some better 

 songster, that, unless they are removed from hearing the parents, at the 



