"What next?" asked Larry.
"I think we ought to take a look around," I replied in the same low tones. "We'll climb the wall here and take a flash about. The whole place ought to be plain as day from that height."
Huldricksson, his blue eyes alert, nodded. With the greatest difficulty we clambered up the broken blocks.
To the east and south of us, set like children's blocks in the midst of the sapphire sea, lay dozens of islets, none of them covering more than two square miles of surface; each of them a perfect square or oblong within its protecting walls.
On none was there sign of life, save for a few great birds that hovered here and there, and gulls dipping in the blue waves beyond.
We turned our gaze down upon the island on which we stood. It was, I estimated, about three-quarters of a mile square. The sea wall enclosed it. It was really an enormous basalt-sided open cube, and within it two other open cubes. The enclosure between the first and second wall was stone paved, with here and there a broken pillar and long stone benches. The hibiscus, the aloe tree, and a number of small shrubs had found place, but seemed only to intensify its stark loneliness.
"Wonder where the Russian can be?" asked Larry.
I shook my head. There was no sign of life here. Had Marakinoff gone—or had the Dweller taken him, too? Whatever had happened, there was no trace of him below us or on any of the islets within our range of vision. We scrambled down the side of the gateway. Olaf looked at me wistfully.
"We start the search now, Olaf," I said. "And first, O'Keefe, let us see whether the grey stone is really here. After that we will set up camp, and while I unpack, you and Olaf search the island. It won't take long."
Larry gave a look at his service automatic and grinned. "Lead on, Macduff," he said. We made our way up the steps, through the outer enclosures and into the central square, I confess to a fire of scientific curiosity and eagerness tinged with a dread that O'Keefe's analysis might be true. Would we find the moving slab and, if so, would it be as Throckmartin had described? If so, then even Larry would have to admit that here was something that theories of gases and luminous emanations would not explain; and the first test of the whole amazing story would be passed. But if not—And there before us, the faintest tinge of grey setting it apart from its neighbouring blocks of basalt, was the moon door!