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 occasions 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 Épernay. Its inhabitants were not set at liberty, while the pigeons of the neighboring 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 Épernay. 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 Épernay to Chalons in a strange wagon left for Épernay, and there found their wandering home. How did they succeed in tracing their way back from Épernay to Chalons, and in finding 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 Bapatume, 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 Évreux, taking up the reverse of a journey made some days before on the railroad. At Évreux, 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 grown strong and has learned to escape by flight from the pursuer, he
- ↑ 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 rolling 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.