"Why, Professor, that looks a whole lot like an outline map of the Hudson Bay Territory, Canada, and Newfoundland. There's the mouth of the St. Lawrence, sure! What are you doing?" "I have been drawing," said the gentleman, solemnly, "an outline of what I see upon that luminous body floating there in space," and he pointed a trembling finger at the strange planet. "Impossible!" cried Mark. "I do not think I am losing my mind," said the professor, testily. "It remains, however, that the outline of certain bodies of water and of land upon that luminous globe seem to be the exact counterpart of land-bodies and water-bodies on the Earth." "But what does it mean?" questioned Jack. "If I knew that," grumbled the professor, returning to his instrument, "I should feel better satisfied." That some strange--some really wonderful--change had taken place in their physical surroundings, too, there could be no doubt. But what it was the boys could not imagine. Of one thing they were sure, however: The law of gravitation had been partly overcome. And a second fact was discernible: There was a surprising rarity to the air they breathed, and had been since the fall of volcanic ashes had ceased. In lifting the heavier tools they handled it was noticeable that they seemed lighter. And Andy Sudds surprised them all, when it became necessary to roll a log out of the way of the flying machine, by seizing the heavy timber and lifting it with the ease with which one might lift a small sapling. "We've all become strong men--professional strong men," gasped Jack. "Wash is the champion jumper and Andy beats old Samson, I declare! What do you make of it, Mark?" "If the professor cannot explain it, don't expect me to do so," returned his chum. "It am de seriousest question dat has ebber come befo' us," declared Washington, looking wondrous wise. "Disher jumpin' has always been in ma fambly, howebber. We had some great jumpers down Souf befo' de War." The boys hurried to finish the repairs. It was some time after midnight when they pronounced the _Snowbird_ again ready for flight. The professor had to be urged more than once to leave his telescope, however; and then he insisted upon setting it up on the deck of the flying machine. He would not discuss the situation at all; but his serious visage and his anxious manner betrayed to them all that he was disturbed indeed by the strange, pale planet he had so closely examined. Mr. Roebach turned loose his dogs again and climbed gingerly aboard the flying machine. "I've never been up in the air," he said, "and I must admit that I am somewhat more afraid of a flying machine than I am of an earthquake." "No more earthquakes in mine, thank you!" cried Jack. "I'd rather sail on a kite than go through what we did yesterday."