Ice now came rolling down in great quantities and with irresistible force, and at last the ship was whirled into the much-dreaded pack, where she became firmly embedded, and drifted along with it before the gale into the unknown regions of the North all that night.  To add to their distress and danger a thick fog overspread the sea, so that they could not tell whither the ice was carrying them, and to warp out of it was impossible.  There was nothing for it therefore but to drive before the gale, and take advantage of the first opening in the ice that should afford them a chance of escape.

Towards evening of the following day the gale abated, and the sun shone out bright and clear; but the pack remained close as ever, drifting steadily towards the north.

“We’re far beyond the most northerly sea that has ever yet been reached,” remarked Captain Guy to Fred and Singleton, as he leaned on the weather bulwarks, and gazed wistfully over the fields of ice in which they were embedded.

“I beg your pardon for differing, Captain Guy, but I think that Captain Parry was farther north than this when he attempted to reach the Pole,” remarked Saunders, with the air of a man who was prepared to defend his position to the last.

“Very possibly, Mr. Saunders; but I think we are at least farther north in this direction than any one has yet been; at least I make it out so by the chart.”

“I’m no sure o’ that,” rejoined the second mate positively; “charts are not always to be depended on, and I’ve heard that whalers have been up hereabouts before now.”

“Perhaps you are right, Mr. Saunders,” replied the captain, smiling; “nevertheless, I shall take observations, and name the various headlands, until I find that others have been here before me.—­Mivins, hand me the glass; it seems to me there’s a water-sky to the northward.”

“What is a water-sky, captain?” inquired Fred.

“It is a peculiar, dark appearance of the sky on the horizon, which indicates open water; just the reverse of that bright appearance which you have often seen in the distance, and which we call the ice-blink.”

“We’ll have open water soon,” remarked the second mate authoritatively.

“Mr. Saunders,” said Mivins, who, having just finished clearing away and washing up the debris and dishes of one meal, was enjoying in complete idleness the ten minutes of leisure that intervened between that and preparations for the next—­“Mr. Saunders, sir, can you hinform me, sir, ’ow it is that the sea don’t freeze at ’ome the same as it does hout ’ere?”

The countenance of the second mate brightened, for he prided himself not a little on his vast and varied stores of knowledge, and nothing pleased him so much as to be questioned, particularly on knotty subjects.

“Hem! yes, Mivins, I can tell ’ee that.  Ye must know that before fresh water can freeze on the surface the whole volume of it must be cooled down to 40 degrees, and salt water must be cooled down to 45 degrees.  Noo, frost requires to be very long continued and very sharp indeed before it can cool the deep sea from the top to the bottom, and until it is so cooled it canna freeze.”