The exodus of the Kalmucks is a sufficient answer to every argument that can be advanced on the subject of primitive migration by land. In eight months, in spite of the intense extremes of cold and heat, of incessant attacks from implacable enemies, and in spite of hunger and thirst, this nation had accomplished a distance equal in a straight line to one-eighth of the circumference of the earth. If we take into consideration all the enforced detours, we ought probably to double the amount. With such facts as these, how can we doubt the possibility of still longer expeditions for a tribe advancing peacefully by stages, and having only to contend against the difficulties presented by the soil or wild beasts? CHAPTER XVII. MIGRATIONS BY SEA.—POLYNESIAN MIGRATIONS.—MIGRATIONS TO NEW ZEALAND. I. The greater number of the defenders of autochthony allow that there is no fundamental impossibility in migration by land, but maintain that it is different in migrations by sea. The peopling of America, and especially that of Polynesia, by emigrants from our great continent, is, in their opinion, far more than could possibly be undertaken or accomplished by nations unacquainted with the science of astronomy, and the improved method of navigation. According to them, geographical conditions, winds and currents, must oppose an insurmountable obstacle to any enterprise of this nature. Starting from Polynesia, let us see how much truth there is in these assertions. This will be taking, so to speak, the bull by the horns, for no other part of the globe seems to justify to such an extent, the opinions of autochthonists. II. Polynesia is not quite so isolated as we are accustomed to think. A study of the map alone should be sufficient to justify us in holding that a maritime people, accustomed to the navigation of the Malay Archipelago, might, on some occasion, have pushed as far as New Guinea. This fact is now established above all dispute. Beyond New Guinea, the Archipelago of New Britain and the Solomon Islands would put, so to speak, any fairly adventurous navigators on their way to the Fiji Islands; once arrived at this archipelago, however little they may have been impelled by the spirit of discovery, they must easily have reached Polynesia properly so called. New Zealand to the south, and the Sandwich Islands to the north, remain, however, beyond the limits of this route, as it is pointed out by geography.