I stood in the broad moonlight, near the north-east angle of the great pile, at the twelfth stone from the corner. A random fancy struck me, that I might turn this stone by pushing it inward on the left side. I leant against it with all my weight, and tried to move it on the imaginary pivot. Did it give way a fraction of an inch? No, it must have been mere fancy. Let me try again. Surely it is yielding! Gracious Osiris, it has moved an inch or more! My heart beats fast, either with fever or excitement, and I try a third time. The rust of centuries on the pivot wears slowly off, and the stone turns ponderously round, giving access to a low dark passage. It must have been madness which led me to enter the forgotten corridor, alone, without torch or match, at that hour of the evening; but at any rate I entered. The passage was tall enough for a man to walk erect, and I could feel, as I groped slowly along, that the wall was composed of smooth polished granite, while the floor sloped away downward with a slight but regular descent. I walked with trembling heart and faltering feet for some forty or fifty yards down the mysterious vestibule: and then I felt myself brought suddenly to a standstill by a block of stone placed right across the pathway. I had had nearly enough for one evening, and I was preparing to return to the boat, agog with my new discovery, when my attention was suddenly arrested by an incredible, a perfectly miraculous fact. The block of stone which barred the passage was faintly visible as a square, by means of a struggling belt of light streaming through the seams. There must be a lamp or other flame burning within. What if this were a door like the outer one, leading into a chamber perhaps inhabited by some dangerous band of outcasts? The light was a sure evidence of human occupation: and yet the outer door swung rustily on its pivot as though it had never been opened for ages. I paused a moment in fear before I ventured to try the stone: and then, urged on once more by some insane impulse, I turned the massive block with all my might to the left. It gave way slowly like its neighbour, and finally opened into the central hall.