The season was now so far advanced that the sun, circling as always in this latitude around and around the heavens, was above the horizon nearly half the time, and during the other half there was almost no darkness--only a gray twilight.
The temperature this day was in the minus fifties, as evidenced by the frozen brandy and the steam-enshrouded dogs; but bubbles in all my spirit thermometers prevented a definite temperature reading.

These bubbles were caused by the separation of the column, owing to the jolting of the thermometer with our constant stumbling over the rough ice of the polar sea.

The bubbles might be removed at night in camp, but this required some time, and the accurate noting of temperatures during our six or seven weeks' march to the Pole and back did not seem sufficiently vital to our enterprise to make me rectify the thermometer every night.

When I was not too tired, I got the bubbles out.
Again Marvin, who was still pioneering the trail, gave us a fair march of fifteen miles or more, at first over heavy and much-raftered ice, then over floes of greater size and more level surface.

But the reader must understand that what we regard as a level surface on the polar ice might be considered decidedly rough going anywhere else.
The end of this march put us between 85 deg.