82 On the Migration of North American Birds. 



an Intricate subject ; for the elucidation of which, I have myself pos- 

 sessed some op^portunities, by witnessing the migration of birds, in 

 three very distinct portions of America. 



That instinct is truly mysterious, which, at particular seasons of 

 the year, teaches birds to take wing and leave their native haunts, 

 pursuing their onward course, sometimes across arms of the sea, and 

 in most cases over rivers, mountains and forests, into far distant coun- 

 tries. It is equally surprising, that many of them, commencing their 

 migrations in summer, should thus anticipate the cold ; while others 

 return from southern climes, before the snows of the north have dis- 

 appeared, and whilst winter still "lingers in the lap of spring." 



Among animals and birds, we often discover a train of actions, all 

 adapted to produce a certain effect, by the agency of certain means, 

 without the exhibition of any part of a regular chain of thought, the 

 essential characteristic of reason ; this substitute for reason is called 

 instinct, a term which has given rise to many unsatisfactory theories. 

 I shall, therefore, pass them over with a few brief remarks, on the 

 difference between instinct and reason. 



When certain species of birds, at their first season of breeding, 

 being without experience, build all their nests alike, both in form and 

 materials, this may be called the result of instinct. On the other 

 hand, when man guards against danger, or makes provision for the 

 wants of life, or seeks relief from diseases, by the application of 

 medicines, he acts from reason, because he is instructed by the ex- 

 perience of the past. When birds, at certain seasons of the year, 

 change the climate, in anticipation of cold or heat, they act from 

 instinct, because, to many of them, it is their first migration ; and as 

 they often migrate singly, and not in flocks, in such cases no expe- 

 rience can aid them. On the other hand, when man makes provis- 

 ion for the changes of seasons and climates, he acts from reason, 

 and is instructed by his own experience, or the experience of others. 



Whatever difficulties there may be, in accounting for that myste- 

 rious principle in birds, called instinct, ard which induces them, at 

 certain seasons, to change their abode, and again, after an interval of 

 six months, to return to the neighborhood where, the year before, 

 they reared their young ; the facts of these migrations are incontro- 

 vertible, and the reasons why they take place are becoming more 

 and more apparent. 



Those birds that migrate, are, from the very structure of their 

 bodies admirably adapted to rapid and continued flight. Their 



