Where a little rill of sweet water sprang from between two boulders, boiling out white sand from the depths of its spring, was the print of a bear's paw. Many of these marks Jack and Mark saw for themselves; but Andy was quick to point them out as he led the way up the steep path. Their progress was necessarily slow because of the aged professor. Although the scientist was not the man to retard the party, Andy would let nobody take the lead but himself, so that he could watch the old man's flagging steps and call a halt whenever he thought it best for Mr. Henderson to rest. "You are babying me, Andy!" ejaculated the professor, with some irritation. "You're the most important person in this party, sir," declared the hunter. "We can lose any other person and not miss him much. But without you we'd be without a head." Therefore, when they had clambered through the last steep cut and reached the farther slope of the cliff, the hunter called a halt and built a camp, determined to bivouac here although the oil man assured him that they were now less than twenty miles from Aleukan. A few hours later they awoke to find the sun rising once more and the heat of the exposed hillside becoming unbearable. Were it not for the wonderful clearness of the air they could not have stood the heat at all. But all agreed that they would better descend the hill to the forest and so be sheltered from the direct rays of the sun. The bearing of their extra clothing in this tropical heat was an effort, and they were all glad to find shelter beneath the huge-limbed trees at the foot of the slope. There they lay in the shade and discussed the direction they should travel from this point. It was not until this time they discovered that their pocket compasses pointed the north as being in a totally different direction from what they had supposed. Phineas Roebach had declared the native settlement of Aleukan to be directly north and west of the place where he had tapped the mud-spouter. But now, although he was positive of the contour of the hills and the line of peaks of the Endicott Range under which Aleukan was established, their compasses made the direction southwest. "Not at all strange, sir," said Professor Henderson. "In becoming detached from the old earth, our new planet was shifted a good bit, and that which was to the north is now almost west. If, by chance, this island in the air includes that point on the earth's surface which once represented the most northerly spot--the North Pole, in fact--it is the North Pole no longer. The magnetic needle points instead to a new North Pole, established on this fragment of a planet since it was shot off into space from its parent world."