The Ocean and its Wonders, Robert Michael Ballantyne [portable ebook reader txt] 📗

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"The influence of this long intense darkness was most depressing. Even our dogs, although the greater number of them were natives of the arctic circle, were unable to withstand it. Most of them died from an anomalous form of disease, to which I am satisfied, the absence of light contributed as much as extreme cold." Quoting from his journal he says: "I am so afflicted with the insomnia of this eternal night, that I rise at any time between midnight and noon. I went on deck this morning at five o'clock. It was absolutely dark; the cold not permitting a swinging lamp, there was not a glimmer came to me through the ice-crusted window-panes of the cabin. While I was feeling my way, half puzzled as to the best method of steering clear of whatever might be before me, two of my Newfoundland dogs put their cold noses against my hand, and instantly commenced the most exuberant antics of satisfaction. It then occurred to me how very dreary and forlorn must these poor animals be, at atmospheres 10 degrees above zero in-doors and 50 degrees below zero without--living in darkness, howling at an accidental light, as if it reminded them of the moon--and with nothing, either of instinct or sensation, to tell them of the passing hours, or to explain the long lost daylight. They shall see the lantern more frequently."

Yet this state of midnight darkness is not altogether unmitigated. There are a few ameliorating influences at work, the nature of some of which we will treat of in the next chapter. Among others, the moon frequently shines there with great brilliancy in winter. Dr Kane says that in October the moon had reached her greatest northern declination: "She is a glorious object. Sweeping around the heavens, at the lowest part of her curve she is still 14 degrees above the horizon. For eight days she has been making her circuit with nearly unvarying brightness. It is one of those sparkling nights that bring back the memory of sleigh-bells and songs and glad communings of hearts in lands that are far away."

But despite all the varied and transient beauties of the northern skies in winter, the long arctic night is undoubtedly depressing in the extreme. In these regions men speak of being able to read the thermometer on the 7th of November at noonday "without a light," as being matter for gratulation. The darkness still before them at that time would be of about three months' duration, and even then they would only get back to a species of twilight.

The cold experienced by these navigators of the northern seas is terribly intense. Their thermometers have frequently indicated a temperature as low as 75 degrees below zero, or 107 degrees of frost, on Fahrenheit's scale. The thermometers of arctic explorers are always filled with spirits of wine, as quicksilver freezes at about 40 degrees below zero, and is therefore unsuitable. It would be frozen, indeed, the greater part of the winter.

Dr Kane says: "At such temperatures chloric ether became solid, and carefully prepared chloroform exhibited a granular pellicle on its surface. Spirits of naphtha froze at 54 degrees below zero, and oil of sassafras at 49 degrees. The oil of winter-green was in a flocculent state at 56 degrees, and solid at 63 degrees.

"The exhalations from the surface of the body invested the exposed or partially clad parts with a wreath of vapour. The air had a perceptible pungency upon inspiration, but I could not perceive the painful sensation which has been spoken of by some Siberian travellers. When breathed for any length of time, it imparted a sensation of dryness to the air-passages. I noticed that, as it were involuntarily, we all breathed guardedly, with compressed lips."

Now, strange to say, this extremely low temperature does not affect the ocean to any great depth. Just below the ice, in cold such as the above, the sea was found to be 29 degrees _above_ zero. No doubt, deeper down, the temperature was still warmer. We have heard it said, that when men chance to fall into the water in cold regions, in the depth of winter, it feels at first rather warm and agreeable! On scrambling out again, however, their condition is not enviable; for in a few minutes the keen frost causes their garments to become as hard as boards.

Much light has been thrown on the fact of the existence of under and upper currents in the sea, by the phenomena of the arctic regions, and some of the questions to which these currents give rise are so interesting that we shall treat of them in a new chapter.


CHAPTER TWELVE.


QUESTION OF AN OPEN SEA ROUND THE POLES--UPPER AND UNDER CURRENTS OF THE OCEAN--CAUSE THEREOF--HABITS OF THE WHALE AS BEARING ON THE QUESTION-- DR. KANE'S DISCOVERY OF AN OPEN SEA IN THE FAR NORTH--NOTES ON THE EXPEDITION--A BEAR-HUNT.

It was long and very naturally supposed that the impenetrable ice of the arctic regions extended to, and, as it were, sealed up the pole. But from time to time philosophic observers of Nature's laws began to hint their opinion that there is an open ocean around the pole; and of late years this opinion has all but been converted into a firm belief.

Maury remarks, that like air--like the body--the ocean _must_ have a system of circulation for its waters. And an attentive study of the currents of the sea, and a close examination of the laws which govern the movements of the waters in their channels of circulation through the ocean, will lead us irresistibly to the conclusion that always, in summer and winter, there must be, somewhere within the arctic circle, a large body of open water.

There is an under-current setting from the Atlantic, northward through Davis' Straits, into the Arctic Ocean, and a surface-current setting out.

The fact is proved beyond a doubt by the observations of arctic explorers, who have seen immense icebergs drifting rapidly northward against a strong current. This apparent anomaly could only be accounted for by the fact that a powerful undercurrent carried them northward; and as at least seven times more of these bergs must have been under than above water, we can easily understand how the under-current, acting on the larger mass of each berg, had power to carry it against the surface-current.

This under-current is _warm_, while the upper-current is _cold_. Now we know that according to Nature's laws, heated water, like heated air, rises to the surface, and cold water sinks to the bottom. How, then, comes this warm current to be underneath the cold, as soundings have proved it to be? It is owing to the fact that the under-current is much salter, and therefore heavier (despite its warmth), than the surface-current; which latter, being mingled with the drainage and ice-masses of the arctic regions, is comparatively fresh, and therefore light as well as cold.

The hot and salt waters of the tropics are carried north by the Gulf Stream. There are here two counteracting agents at work. Heat inclines the Gulf Stream to rise; saltness inclines it to sink. During the first part of its journey, as we know, its great heat prevails over the other influence, and it flows as a surface-current. But, at a certain point in its northward route, it meets with the cold, brackish, ice-bearing currents that flow out of the arctic basin. Having lost much of its heat (though still possessing a great deal more than the arctic currents), the saltness of the Gulf Stream prevails; it dips below the polar waters, and thenceforth continues its course as an under-current, salt, and comparatively warm.

To state the matter briefly: The hot water, which _ought_ to keep on the surface because of its heat, is sunk by its superabundant salt; and the cold water, which _ought_ to sink because of its cold, is buoyed on the surface because of its want of salt.

Now arises the question--what becomes of the great quantity of salt that is thus being carried perpetually into the polar basin? Manifestly it must be carried out again by the surface-current, otherwise the polar basin would of necessity become a basin of salt. The under-current _must_, therefore, rise to the surface somewhere near the pole, with its temperature necessarily only a little, if at all, below the freezing-point--which, be it observed, is a _warm_ temperature for such regions. Here, then, where the warm waters from the south rise to the surface, it is supposed this open Arctic Ocean must exist.

So much for theory. Now for facts that have been observed, and that tend, more or less, to corroborate this proposition of an open polar sea. The habits of the whale have gone far to prove it. The log-books of whalers have for many years been carefully examined and compared by scientific men. These investigations have led to the discovery "that the tropical regions of the ocean are to the `right' whale as a sea of fire, through which he cannot pass, and into which he never enters." It has also been ascertained that the same kind of whale which is found off the shores of Greenland, in Baffin's Bay, etcetera, is found in the North Pacific, and about Behring's Straits; and that the `right' whale of the southern hemisphere is a different animal from that of the northern. How, then, came the Greenland whales to pass from the Greenland seas to the Pacific? Not by the Capes Horn or Good Hope; the "sea of fire" precluded that. Clearly there was ground here for concluding that they did so through the (supposed) open sea lying beyond, or rather within, the frozen ocean.

It is true the objection might be made, that the same kind of whale which exists in the North Pacific exists also in the North Atlantic, although they never cross over to see each other. But another discovery has met this objection.

It is the custom among whalers to have their harpoons marked with date and name of ship, and Dr Scoresby, in his work on arctic voyages mentions several instances of whales having been taken near Behring's Straits, with harpoons in them bearing the stamp of ships that were known to cruise in the Greenland seas; and the dates on the harpoons were so recent as to preclude the supposition that the said whales had, after being struck, made a voyage round the capes above mentioned,--even were such a voyage possible to them. All this does not, indeed, absolutely prove the existence of an open arctic sea, but it does, we think, prove the existence of at least an _occasionally_ open sea there, for it is well known that whales cannot travel such immense distances under ice.

But the most conclusive evidence that we have in regard to this subject is the fact, that one of the members of Dr Kane's expedition, while in search of Sir John Franklin, did actually, on foot, reach what we have every reason to believe was this open sea; but not being able to get their ship into it, the party had no means of exploring it, or extending their investigations. The account of this discovery is so interesting, and withal so romantic, that we extract a few paragraphs relating to it from Kane's work.

After spending the dreary winter in the ice-locked and unexplored channels beyond the head of Baffin's Bay, Kane found his little ship still