786 POPULAR SCIENCE MONTHLY. 



Newton (Encyclopaedia Britannica, article Birds) says : " We 

 have here more than enough to excite our wonder, and instead are 

 brought face to face with perhaps the greatest mystery which the 

 whole animal kingdom presents a mystery which attracted the 

 attention of the earliest writers, and can in its chief point be no 

 more explained by the modern man of science than by the simple- 

 minded savage or the poet or prophet of antiquity. Some facts are 

 almost universally known, and have been the theme of comment in 

 all ages and in all lands. The hawk that stretches her wings toward 

 the south is as familiar to the latest Nile-boat traveler or dweller on 

 the Bosporus as of old to the author of the book of Job. 



" The autumnal thronging by myriads of waterfowl of the 

 rivers of Asia is witnessed by the modern sportsman as it was of old 

 by Homer. . . . But there is no need to multiply instances. The 

 flow and ebb of the mighty feathered wave has been sung by poets 

 and reasoned by philosophers, has given rise to proverbs and en- 

 tered into popular superstitions, and yet we must say of it still that 

 our ignorance is immense." 



While this author does not exaggerate either the interest or our 

 ignorance of the life of birds, which goes on in regions that are 

 almost inaccessible and unknown, there is no reason to suppose their 

 migrations are any more mysterious than most biological problems; 

 for the modern man of science is little more able than the simple- 

 minded savage or the poet or prophet to tell how all the co-ordinated 

 faculties of a predaceous animal are so thrown into action by the 

 stimulus of hunger as to lead to the pursuit and capture of prey; 

 yet there is no mystery in the physiology of hunger, for, while 

 there is much we do not understand, we do know that hunger 

 incites actions which are responsive, or adapted for satisfying 

 hunger. 



So also it may be possible to make progress in the study of the 

 meaning of migration in spite of our ignorance of the nature of the 

 impulse which excites and determines it; and while I gratefully 

 acknowledge my debt to Newton for the facts, I am not able to agree 

 with him that there is anything distinctively or peculiarly mysterious 

 in the subject. 



While there is reason to believe almost every bird of temperate 

 and arctic climates is migratory to some degree, those which simply 

 range over a wider area at one season than at another present nothing 

 notable, and it is only in regions which are almost or quite deserted 

 by birds for part of the year that their migrations attract the atten- 

 tion of students. As many birds which are most valued for food 

 are found in temperate regions for only a short time in the spring 

 and fall, sportsmen and hunters and all who pursue them for food 



