i>2 Dr. Jenner on the Migration of Birds. 



Now, may not this be almost considered as daring a flight as 

 that of the bird which crosses the Atlantic? For it is not at 

 all probable that the shores of this country can be visible to 

 the flock when they set out. 



Again : Is there not something as extraordinary in the pi- 

 geon, which can in a few hours find out its home, though 

 taken away in a box and totally excluded from the light, to 

 the distance of two hundred miles, as in that bird which quits 

 one shore to seek another, whatever may be the extent of in- 

 tervening seas ? The fact seems to be, that we, the little lords 

 of the creation, are too prone to measure the sentient principle 

 in animals by the scale of our own ideas, and thus, unwillingly, 

 allow them to possess faculties which may surpass our own, 

 though peculiarly appropriate to their respective natures ; but 

 a little reflection must compel us to confess, that they are en- 

 dowed with discriminating powers totally unknown to, and 

 for ever unattainable by man. I have no objection to admit 

 the possibility that birds may be overtaken by the cold of 

 winter, and thus be thrown into the situation of other animals 

 which remain torpid at that season ; though I must own I 

 never witnessed the fact, nor could I ever obtain evidence on 

 the subject that was to me satisfactory : but as it has been 

 often asserted, may I be allowed to suppose, that some decep- 

 tion might have been practised with the design of misleading 

 those to whom it might seem to have appeared obvious ? For 

 far be it from me to insinuate that the subject has been wil- 

 fully misrepresented by those naturalists who have stated it 

 as a fact. Yet how careful should we be in the investigation 

 of all subjects in natural history which may captivate by their 

 apparent novelty ! 



If birds crept into holes and crevices to hibernate, would 

 they not, like quadrupeds, creep out again in a languid state, 

 their fat all absorbed, and their bodies emaciated? We see 

 this fact exemplified in the hedge-hog, one of the most re- 

 markable of our hibernating animals, which retires to its hut 

 at the approach of winter, with vast stores of fat placed in 

 every situation where nature could find room for it. This fat 

 is its only source of nutrition for the winter, which, by the 

 time the sun rouses it to fresh life and activity, is exhausted, 

 and the animal comes forth thin and emaciated. But the case 

 with birds is extremely different. If, on the first day of its 

 appearance, a martin, a swift, or a redstart be examined, it 

 will be found as plump and fleshy as at any season during its 

 stay; it appears also as strong on the wing, and as full of ac- 

 tivity at that period as at any other during its abode with us. 



How 



