LIFE OF WILSON. CX ci 



I have, at this time, in the press, a memoir on the migration 

 and torpidity of these birds. I am confident that I shall be 

 able to convince every candid philosopher, that great num- 

 bers of swallows, of different species, do occasionally pass 

 into a state of torpidity, more or less profound, not merely 

 ' in some remote quarter of America,' but in the vicinity of 

 our capital cities, where there are some men of genuine obser- 

 vation and inquiry, and who are as little propense to believe 

 the marvellous in natural history, as any philosophers elsewhere. 



" I do not suppose that all the swallows of North America 

 become torpid. It is my present opinion, and it was my opinion 

 when I published the * Fragments' in 1799, that the swallows, 

 in general, are migratory birds. But subsequent and very ex- 

 tensive inquiries have convinced me, that the instances of tor- 

 pid swallows are much more frequent than I formerly supposed 

 they were; and that there are two species of the genus Hirun- 

 do, which are peculiarly disposed to pass the brumal season in 

 the cavities of rocks, in the hollows of trees, and in other simi- 

 lar situations, where they have often -been found in a soporose 

 state. These species are the Hirundo riparia, or sand swal- 

 low; and the H. pelasgia, which we call chimney swallow. 

 There is no fact in ornithology better established, than THE 

 FACT of the occasional torpidity of these two species of Hi- 

 rundo!"* 



It is not strange that the " very extensive" inquiries of our 

 learned professor should have had a result so different from 

 those of Wilson, an ornithologist infinitely better qualified than 

 himself to investigate a question of this kind, by his zeal, his 

 capacity, and his experience. Who those men of genuine ob- 



* Tilloch's Philosophical Magazine, vol. 35, p. 241. 



"Naturalists," says Dr. Barton in another place, " have not always been 

 philosophers. The slight and superficial manner in which they have examined 

 many of the subjects of their science; the credulity which has accompanied 

 them in their researches after truth; and the precipitancy with which they have 

 decided upon many questions of importance; are proofs of this assertion." Me- 

 moir concerning the fascinating faculty of serpents. 



