THE LAW* OF ORIENTATION AMONG ANIMALS. 495 



around its carriage, but by the sense of direction, which would give it 

 a subjective idea of its position in respect to its home. 



Practice has in every case confirmed our theory. We have had occa- 

 sions to make some interesting observations, and we will now cite 

 certain facts which relate directly to our discussion. 1 



A pigeon carriage was stationed for twenty-four hours at Eperuay. 

 Its inhabitants were not set at liberty, while the pigeons of the neigh- 

 boring wagons, after remaining quiet for two hours, were taken to some 

 distance to be released. 



The next morning the carriages were taken to Chalons, with the 

 exception of the carriage from which the pigeons had not flown at 

 Epernay. Those pigeons were distributed among the other carriages, 

 which were exactly like the first in pattern. At Chalons the cotes 

 were opened and these pigeons set free. Some of those which had 

 made the journey from Epernay to Chalons in a strange wagon left for 

 Epernay, and there found their wandering home. How did they suc- 

 ceed in tracing their way back from Epernay to Chalons, and in find- 

 ing their carriage in a place of which they could know nothing ? Only 

 the law of retracement can explain this action. We have, moreover, 

 repeated this curious experiment many times. 



While a pigeon carriage was stationed at the Chateau of Morchies 

 two pigeons went astray. They were found again at Bapatune, the 

 last stopping place of the carriage. One was taken, the other escaped. 

 Its course of flight was reported to us from all the places where its 

 carriage had stopped. It arrived in this way at Houdain. From 

 there it left for Evreux, taking up the reverse of a journey made 

 some days before on the railroad. At Evreux, where the carriage had 

 stopped for some months, we succeeded in capturing it. Is not the 

 retracing of this journey step by step the best proof which could be 

 given in support of our theory? By means of the law of retracement 

 we can almost always determine the exact point at which to find our 

 lost pigeon. We thus succeed in decreasing the number of losses which 

 would otherwise be numerous and difficult to repair. 



The return of a pigeon to a moving home is not an exceptional thing; 

 we might cite many examples of the same sort borrowed from the 

 history of birds. 



The birds of prey which live in the forests of Argonne and of Ardennes- 

 or even in the solitudes of the Alps, find in spring in their native region 

 everything that is necessary to their subsistence — young broods and 

 game in abundance. But when autumn comes, when the game has 

 grow r n strong and has learned to escape by flight from the pursuer, he 



1 Our experiments have settled one interesting point. According to M. Daresre, 

 eggs shaken with some violence for a considerable time will not hatch out. We 

 have proved that rolliug over roads, over a pavement, or on a railroad, when the 

 eggs are shipped, in no way alters the conditions of hatching. We may say with 

 certainty that in a movable cote the pigeons hatch with the same regularity as 

 their kindred in ordinary cote. 



