also brought out that the same kind of whale that is found off the shores of Greenland, in Baffin's Bay, &c., is found also in the North Pacific, and about Behring's Strait, and that the right whale of the northern hemisphere is a different animal from that of the southern. Thus the fact was established that the harpooned whales did not pass around Cape Horn or the Capo of Good Hope, for they were of the class that could not cross the equator. In this way we were furnished with circumstantial evidence affording the most irrefutable proof that there is, at times at least, open-water communication through the Arctic Sea from one side of the continent to the other, for it is known that the whales cannot travel under the ice for such a great distance as is that from one side of this continent to the other. But this did not prove the existence of an open sea there; it only established the existence—the occasional existence, if you please—of a channel through which whales had passed. Therefore we felt bound to introduce other evidence before we could expect the reader to admit our proof, and to believe with us in the existence of an open sea in the Arctic Ocean.
424. The under current into the Arctic Ocean—its influences.—There is an under current setting from the Atlantic through Davis' Strait into the Arctic Ocean, and there is a surface current setting out. Observations have pointed out the existence of this under current there, for navigators tell of immense icebergs which they have seen drifting rapidly to the north, and against a strong surface current. These icebergs were high above the water, and their depth below, supposing them to be parallelepipeds, was at least seven times greater than their height above. No doubt they were drifted by a powerful under current. Now this under current comes from the south, where it is warm, and the temperature of its waters is perhaps not below 30°; at any rate, they are comparatively warm. There must be a place somewhere in the arctic seas where this under current ceases to flow north, and begins to flow south as a surface current; for the surface current, though its waters are mixed with the fresh waters of the rivers and of precipitation in the polar basin, nevertheless bears out vast quantities of salt, which is furnished neither by the rivers nor the rains. These salts are supplied by the under current; for as much salt as one current brings in, other currents must take out, else the polar basin would become a basin of salt; and where the under current transfers its waters to the
