496 THE LAWS OF ORIENTATION AMONG ANIMALS. 



finds himself forced to abandon the domain which he has devastated; 

 he emigrates to the plains and leads a wandering life, settling tempo- 

 rarily in such regions as offer abundant game. He picks out in the 

 center of his hunting ground temporary shelters, to which he returns 

 every evening until spring brings him back to the solitudes, where he 

 builds his nest. What guides the bird of prey in this long expedition ? 

 Undoubtedly the sense of direction. We can not admit that the bird 

 has a memory sufficiently lasting to retain for many months the recol- 

 lection of all the irregularities of the ground which mark a course of 

 many thousands of kilometers. All the bird's power of observation is 

 in fact concentrated on one object — the chase. Topography is of no 

 consequence to him. Like a registering machine set going at the 

 moment of departure, the sense of direction notes automatically all 

 the road covered by the bird in his pursuit of prey. 



The cormorant and many of the fishing birds sometimes follow for 

 many months the long routes of migrating fishes. Though lost in the 

 midst of the sea, they know well how to return to their homes when 

 their fishing is over. 



Naturalists who have studied orientation have very wrongly noticed 

 only one fact — the return to a single home. They have usually attrib- 

 uted this to a knowledge of the locality, founded on long observation. 

 Such a theory gives no explanation of the facts we have just cited. 

 Have we not shown that the law of retracemeut guides the animal 

 when it wanders away from the known territory, brings him back to a 

 temporary home, and sometimes, after an absence of many months, 

 leads him back to his native region ? 



VII. 



It would be interesting to know whether the theory we have just 

 explained is applicable to man. 



An animal's movements are regulated by the law of preservation, 

 which assigns to him an imperative purpose, leaving him a restricted 

 liberty in the choice of means. Man is actuated by the same law, but 

 instinct is not the only determining cause of his action; he is also 

 endowed with reason. While instinct points out to the animal only 

 one course, reason points out to man many solutions; he chooses freely 

 whichever seems best to him. He can even consider the promptings 

 of instinct of no consequence; thus by suicide and Malthusian prac- 

 tices he may set himself in revolt against the law of preservation of 

 himself and his kind. 



We have attempted to prove that the action of orientation from a 

 distance depends solely on the function of one organ — the sense of 

 direction — which acts to some extent automatically. If a man who is 

 trying to orient himself calls to his aid both reason and observation, 

 the sense of direction, through lack of exercise, becomes atrophied. 

 This is why a well-informed man, who estimates everything that he 



