My attainment of the Pole

by Frederick Albert Cook

The time for observations was at hand, and I returned to take up the sextant. Returning later to the lead, to watch the seas breathe, the cry seemed stilled. The thin ice-sheets were cemented together, and in an open space nearby I had an opportunity to study the making and breaking of the polar ice.

That tiny film of ice which voiced the baby cries spreads the world's most irresistible power. In its making we have the nucleus for the origin of the polar pack, that great moving crust of the earth which crunches ships, grinds rocks, and sweeps mountains into the sea. Beginning as a mere microscopic crystal, successive crystals, by their affinity for each other, unite to make a disc. These discs, by the same law of cohesion, assemble and unite. Now the thin sheet, the first sea ice, is complete, and either rests to make the great field of ice, or spreads from floe to floe and from field to field, thus spreading, bridging and mending the great moving masses which cover the mid-polar basin.

Another law of nature was solved by a similar insignificant incident. In spreading our things out to air and dry (for things will dry in wind and sun, even at a very low temperature), two pieces of canvas were thrown on a hummock. It was a white canvas sled-cover and a black strip of canvas, in which the boat fittings were wrapped. When these strips of canvas were lifted it was found that under the part of the black canvas, resting on a slope at right angles to the sun, the snow had melted and recongealed. Under the white canvas the snow had not changed. The temperature was -41°; we had felt no heat, but this black canvas had absorbed enough heat from a feeble sun to melt the snow beneath it. This little lesson in physics began to interest me, and on the return many similar experiments were made. As the long, tedious marches were made, I asked myself the questions: Why is snow white? Why is the sky blue? And why does black burn snow when white does not?

Little by little, in the long drive of monotony, satisfactory answers came to these questions. Thus, in seeking abstract knowledge, the law of radiation was thoroughly examined. In doing this, there came to me slowly the solution of various problems of animal life, and eventually there was uncovered what to me proved a startling revelation in the incidents that led up to animal coloring in the Arctic. For here I found that the creatures' fur and feathers were colored in accord with their needs of absorbing external heat or of conserving internal heat. The facts here indicated will be presented later, when we deal with the snow-fitted creatures at close range.

One of the impressions which I carried with me of this night march was that the sun seemed low—lower, indeed, than that of midday, which, in reality, was not true, for the observations placed it nine minutes higher. This was an indication of the force of habit. In the northward march we had noted a considerable relative difference in the height of the night sun and that of the day. Although this difference had vanished now, the mind at times refused to grasp the remarkable change.[16]

At the Pole I was impressed by a peculiar uniformity in the temperature of the atmosphere throughout the twenty-four hours, and also by a strange monotone in color and light of sea and sky. I had begun to observe this as I approached the boreal center. The strange equability of light and color, of humidity and of air temperatures extended an area one hundred miles about the Pole. This was noted both on my coming and going over this district.

Approaching the Pole, and as the night sun gradually lifted, an increasing equalization of the temperature of night and day followed. Three hundred miles from the Pole the thermometer at night had been from 10° to 20° lower than during the day. There the shivering chill of midnight made a strong contrast to the burning, heatless glitter of midday. At the Pole the thermometer did not rise or fall appreciably for certain fixed hours of the day or night, but remained almost uniform during the entire twenty-four hours.

This, to a less notable extent, was true also of the barometer. Farther south there had been a difference in the day and night range of the barometer. Here, although the night winds continued more actively than those of the day, the barometer was less variable than at any time on my journey.

At the Pole the tendency of change in force and direction of air currents, observed farther south, for morning and evening periods, was no longer noted. But when strong winds brushed the pack, a good deal of the Polar equalization gave place to a radical difference, giving a period for high and low temperatures; which period, however, did not correspond to the usual hours of day or night. The winds, therefore, seemed to carry to us the sub-Polar inequality of atmospheric variation in temperature and pressure. Many of the facts bearing upon this problem were not learned until later. Subsequently, I learned, also, that strong winds often disturb the Polar atmospheric sameness; but all is given here because of the striking impression which it made upon me at this time.

In the region about the Pole I observed that, although there were remarkable and beauteous color blendings in the sky, the intense contrasts and the spectacular display of cloud effects, seen in more southern regions, were absent.