The first thought that occurred to us after the excitement of discovery had somewhat subsided was that the interior of the earth was in all probability a habitable planet, possessing as it did a life-giving luminary of its own, and our one object was to get into the planet as quickly as possible. A continual breeze from the interior ocean of air passed out of the gulf. Its temperature was much higher than that of the sea on which we sailed, and it was only now that we began to think of laying off our Arctic furs. A closer observation of the interior sun revealed the knowledge that it was a very luminous orb, producing a climate similar to that of the tropics or nearly so. As we entered the interior sphere the sun rose higher and higher above us, until at last he stood vertically above our heads at a height of about 3,500 miles. We saw at once what novel conditions of life might exist under an earth-surrounded sun, casting everywhere perpendicular shadow, and neither rising nor setting, but standing high in heaven, the lord of eternal day. We seemed to sail the bottom of a huge bowl or spherical gulf, surrounded by oceans, continents, islands, and seas. A peculiar circumstance, first noticed immediately after arriving at the centre of the gulf, was that each of us possessed a sense of physical buoyancy, hitherto unfelt. Flathootly told me he felt like jumping over the mast in his newly-found vigor of action, and the sailors began a series of antics quite foreign to their late stolid behavior. I felt myself possessed of a very elastic step and a similar desire to jump overboard and leap miles out to sea. I felt that I could easily jump a distance of several miles. Professor Starbottle explained this phenomenal activity by stating that on the outer surface of the earth a man who weighs one hundred and fifty pounds, would weigh practically nothing on the interior surface of an earth shell of any equal thickness throughout. But the fact that we did weigh something, and that the ship and ocean itself remained on the under surface of the world, proved that the shell of the earth, naturally made thicker at the equator by reason of centrifugal gravity than at the poles, has sufficient equatorial attraction to keep open the polar gulf. Besides this centrifugal gravity confers a certain degree of weight on all objects in the interior sphere. "I'll get a pair of scales," said Flathootly, "an' see how light I am in weight." "Don't mind scales," said the professor, "for the weights themselves have lost weight." "Well, I'm one hundred and seventy-five pounds to a feather," said Flathootly, "an' I'll soon see if the weights are right or not." "The weights are right enough," said the professor, "and yet they are wrong." "An' how can a thing be roight and wrang at the same time, I'd loike to know? We'll thry the weights anyway," said the Irishman.