Now below us, and now above us, for the ship had rolled completely over each time we had passed the point at which we came finally to rest, we had noted the luminosity that Norton had first observed from above the mouth of the crater. Each of us had been doing considerable thinking, and at last young Norton could contain himself no longer.
“I beg your pardon, sir,” he said deferentially, “but you tell us what you think of it; what your theory is as to where we are and why we hang here in midair, and why the ship rolled over every time we passed this point?”
“I can only account for it,” I replied, “upon a single and rather preposterous hypothesis, which is that the Moon is a hollow sphere, with a solid crust some two hundred and fifty miles in thickness. Gravity is preventing us from rising above the point where we now are, while centrifugal force keeps us from falling.”
The others nodded. They too had been forced to accept the same apparently ridiculous theory, since there was none other that could explain our predicament. Norton had walked across the room to read the barometer which he had rather neglected while the ship had been performing her eccentric antics far below the surface of the Moon. I saw his brows knit as he glanced at it, and then I saw him studying it carefully, as though to assure himself that he had made no mistake in the reading. Then he turned toward us.
“There must be something wrong with this instrument, sir,” he said. “It is registering pressure equivalent to that at the Earth’s surface.”
I walked over and looked at the instrument. It certainly was registering the pressure that Norton had read, nor did there seem to be anything wrong with the instrument.
“There is a way to find out,” I said. “We can shut down the insulating generator and open an air-cock momentarily. It won’t take five seconds to determine whether the barometer is correct or not.” It was, of course, in some respects a risky proceeding, but with West at the generator, Jay at the air-cock and Norton at the pump I knew that we would be reasonably safe, even if there proved to be no atmosphere without. The only danger lay in the chance that we were hanging in a poisonous gas of the same density as the earthly atmosphere, but as there was no particular incentive to live in the situation in which we were, we each felt that no matter what chance we might take it would make little difference in the eventual outcome of our expedition.
I tell you that it was a very tense moment as the three men took their posts to await my word of command. If we had indeed discovered a true atmosphere beneath the surface of the Moon, what more might we not discover? If it were an atmosphere, we could propel the ship in it, and we could, if nothing more, go out on deck to breathe fresh air. It was arranged that at my word of command West was to shut off the generator, Jay to open the air-cock, and Norton to start the pump. If fresh air failed to enter through the tube Jay was to give the signal, whereupon Norton would reverse the pump, West start the generator, and immediately Jay would close the air-cock again.
As Jay was the only man who was to take a greater chance than the others, I walked over and stood beside him, placing my nostrils as close to the air-cock as his. Then I gave the word of command. Everything worked perfectly and an instant later a rush of fresh, cold air was pouring into the hull of The Barsoom. West and Norton had been watching the effects upon our faces closely, so that they knew almost as soon as we did that the result of our test had been satisfactory. We were all smiles, though just why we were so happy I am sure none of us could have told. Possibly it was just because we had found a condition that was identical with an earthly condition, and though we might never see our world again we could at least breathe air similar to hers.
I had them start the motors again then, and presently we were moving in a great spiral upward toward the interior of the Moon. Our progress was very slow, but as we rose the temperature rose slowly, too, while the barometer showed a very-slightly-decreasing atmospheric pressure. The luminosity, now above us, increased as we ascended, until finally the sides of the great well through which we were passing became slightly illuminated.
All this time Orthis had remained in irons in his stateroom. I had given instructions that he was to be furnished food and water, but no one was to speak to him, and I had taken Norton into my stateroom with me. Knowing Orthis to be a drunkard, a traitor and a potential murderer I had no sympathy whatsoever for him. I had determined to court-martial him and did not intend to spend the few remaining hours or years of my life cooped up in a small ship with him, and I knew that the verdict of any court, whether composed of the remaining crew of The Barsoom or appointed by the Judge Advocate General of the Navy, could result in but one thing, and that was death for Orthis.
