"Goodwin, during the next two hours we tried every way in our power to force entrance through the slab. The rock resisted our drills. We tried explosions at the base with charges covered by rock. They made not the slightest impression on the surface, expending their force, of course, upon the slighter resistance of their coverings. "Afternoon found us hopeless. Night was coming on and we would have to decide our course of action. I wanted to go to Ponape for help. But Edith objected that this would take hours and after we had reached there it would be impossible to persuade our men to return with us that night, if at all. What then was left? Clearly only one of two choices: to go back to our camp, wait for our men, and on their return try to persuade them to go with us to Nan-Tauach. But this would mean the abandonment of Thora for at least two days. We could not do it; it would have been too cowardly. "The other choice was to wait where we were for night to come; to wait for the rock to open as it had the night before, and to make a sortie through it for Thora before it could close again. "Our path lay clear before us. We had to spend that night on Nan-Tauach! "We had, of course, discussed the sleep phenomena very fully. If our theory that lights, sounds, and Thora's disappearance were linked with secret religious rites of the natives, the logical inference was that the slumber had been produced by them, perhaps by vapours--you know as well as I, what extraordinary knowledge these Pacific peoples have of such things. Or the sleep might have been simply a coincidence and produced by emanations either gaseous or from plants, natural causes which had happened to coincide in their effects with the other manifestations. We made some rough and ready but effective respirators. "As dusk fell we looked over our weapons. Edith was an excellent shot with both rifle and pistol. We had decided that my wife was to remain in the hiding-place. Stanton would take up a station on the far side of the stairway and I would place myself opposite him on the side near Edith. The place I picked out was less than two hundred feet from her, and I could reassure myself now and then as to her safety as it looked down upon the hollow wherein she crouched. From our respective stations Stanton and I could command the gateway entrance. His position gave him also a glimpse of the outer courtyard. "A faint glow in the sky heralded the moon. Stanton and I took our places. The moon dawn increased rapidly; the disk swam up, and in a moment it was shining in full radiance upon ruins and sea. "As it rose there came a curious little sighing sound from the inner terrace. Stanton straightened up and stared intently through the gateway, rifle ready.