Dr. Jenner on the Migration of Birds. 51 



they appear and disappear, their respective habits, and many 

 other observations, have been given with considerable accu- 

 racy by several naturalists who have paid attention to this 

 very curious subject. It is with a view of representing some 

 facts, hitherto unnoticed, chiefly with respect to the cause, which 

 excites the bird, at certain seasons of the year, to quit one 

 country for another, that I communicate the following pages 

 to this learned body. 



But before I proceed to state my observations on this head, 

 it may be necessary to adduce some arguments first, in sup- 

 port of the reality of migration, the fact itself not being gene- 

 rally admitted ; and secondly, against the hypothesis of a state 

 of torpor, or what has been called the hibernating system. 



In the first place, the ability of birds to take immensely long 

 flights is proved by the observations of almost every person 

 conversant with the seas. To the many instances already re- 

 corded, I shall add the following : 



My late nephew, Lieutenant Jenner, on his passage to New- 

 foundland, saw on the 20th of May the hobby hawk. It came 

 on board, and was secured. The day following a swallow came 

 on board. At this time the ship was steeling a course direct 

 for that island, and was not within the distance of an hundred 

 leagues of any land. His brother, the Reverend G. C. Jenner, 

 in crossing the Atlantic, observed an owl (of what species he 

 could not precisely acertain, but he believes it to be the com- 

 mon brown owl) gliding over the ocean with as much apparent 

 ease as if it had been seeking for a mouse among its native 

 fields *. Wild geese have frequently been shot in Newfound- 

 land, whose craps were plentifully stored with maize or In- 

 dian corn ; consequently, these birds must have taken a pretty 

 bold flight in a short space of time, as no corn of this kind is 

 cultivated within a vast distance of that island. These how- 

 ever I do not consider as migrations of any further conse- 

 quence, than just to show the powers of the wing. 



My ingenious friend and neighbour, the late Reverend Na- 

 thaniel 1 hornbury, who had occasionally visited Holland, in- 

 formed me that the pigeons about the Hague make a daily 

 marauding excursion, at certain seasons, to the opposite shore 

 of Norfolk, to feed on vetches, a distance of forty leagues. 



* Mr. Jenner informs me, that in subsequent voyages he has taken, in 

 the Atlantic, several hundred miles from land, the nuthatch, hoopoe, and 

 snipe; and has often seen small birds of the linnet kind. Of the latter, a 

 large nock came OO board, perched on the rigging, appeared very lively, 

 and after adjusting their plumage, and chirping in concert for a kv/ mi- 

 nutes, took their (light in a direction for the Azores. 



(i 2 Now, 



