Physical Geography Of The Sea 1855/7

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How Whales struck on the east Side of the Continent have been taken on the west Side, § 278. — Right Whales can not cross the Equator, 279. — How the Existence of a northwest Passage was proved by the Whales, 280. — Other Evidence in Favor of it, 281. — An under Current sets into the Arctic Ocean, 282. — Evidences of a milder Climate near the Pole, 284. — The Water Sky of Lieutenant De Haven, 285. — This open Sea not permanently in one Place, 286.

278. It is the custom among whalers to have their harpoons marked with date and the name of the ship; and Dr. [William] Scoresby, in his work on Arctic voyages, mentions several instances of whales that have been taken near the Bering’s Strait side with harpoons in them bearing the stamp of ships that were known to cruise on the Baffin’s Bay side of the American continent; and as, in one or two instances, a very short time had elapsed between the date of capture in the Pacific and the date when the "fish" must have been struck on the Atlantic side, it was argued therefore that there was a northwest passage by which the whales passed from one side to the other, since the stricken animal could not have had the harpoon in him long enough to admit of a passage around either Cape Horn or the Cape of Good Hope. The whale-fishing is, among the industrial pursuits of the sea, one of no little importance; and when the system of investigation out of which the wind and current charts have grown was commenced, the haunts of this mammal did not escape attention or examination. The log-books of whalers were collected in great numbers, and patiently examined, coordinated, and discussed, in order to find out what parts of the ocean are frequented by this kind of whale, what parts by that, and what parts by neither. (See Plate IX.)

279. Log-books containing the records by different ships for hundreds of thousands of days were examined, and the observations in them cowordinated for this chart. And this investigation,


as Plate IX. shows, led to the discovery that the tropical regions of the ocean are to the right whale as a sea of fire, through which he can not pass, and into which he never enters. The fact was 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 Bering’s Strait, and that the right whale of the northern hemisphere is a different animal from that of the southern.

280. Thus the fact was established that the harpooned whales did not pass around Cape Horn or the Cape 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 irrefragable 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 can not 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.

281. There is an under current setting from the Atlantic through Davis’s 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 was seven times greater than their height above. No doubt they were drifted by a powerful under current.

282. Now this under current comes from the south, where it is warm, and the temperature of its waters is perhaps not below 32º; 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.

283. These salts are supplied by the under current; for as much salt as one current brings in, other currents (§ 252) must take out, else the polar basin would become a basin of salt; and where the under current transfers its waters to the surface, there is, it is supposed, a basin in which the waters, as they rise to the surface, are at 30º, or whatever be the temperature of the under current, which we know must be above the freezing point, for the current is of water in a fluid, not in a solid state.

An arrangement in nature, by which a basin of considerable area in the frozen ocean could be supplied by water coming in at the bottom and rising up at the top, with a temperature not below 30º, or even 28º — the freezing point of sea water — would go far to mitigate the climate in the regions round about.

284. And that there is a warmer climate somewhere in that inhospitable sea, the observations of many of the explorers who have visited it indicate. Its existence may be inferred also from the well-known fact that the birds and animals are found at certain seasons migrating to the north, evidently in search of milder climates. The instincts of these dumb creatures are unerring, and we can imagine no mitigation of the climate in that direction, unless it arise from the proximity or the presence there of a large body of open water. It is another furnace (§ 60) in the beautiful economy of Nature for tempering climates there.

285. Relying upon a process of reasoning like this, and the deductions flowing therefrom, Lieutenant De Haven, when he went in command of the American expedition in search of Sir John Franklin and his companions, was told, in his letter of instructions, to look, when he should get well up into Wellington Channel, for an open sea to the northward and westward. He looked, and saw in that direction a “water sky.” Captain Penny afterward went there, found open water, and sailed upon it.

286. The open sea in the Arctic Ocean is probably not always in the same place, as the Gulf Stream (§ 54) is not always in one place. It probably is always where the waters of the under current are brought to the surface; and this, we may imagine, would depend upon the freedom of ingress for the under current. Its course may, perhaps, be modified more or less by the ice on the


surface, by changes, from whatever cause, in the course or velocity of the surface current, for obviously the under current could not bring more water into the frozen ocean than the surface current would carry out again, either as ice or water.

287. Every winter, an example of how very close warm water in the sea and a very severe climate on the land or the ice may be to each other, is afforded to us in the case of the Gulf Stream, and the Labrador-like climate of New England, Nova Scotia, and Newfoundland. In these countries, in winter, the thermometer frequently sinks far below zero, notwithstanding that the tepid waters of the Gulf Stream may be found with their summer temperature within one good day’s sail of these very, very cold places.