Having lighted the wick and spread it with his fingers until it flamed up brightly, Kāra turned his back to the arch and carefully examined the rear wall of the room. The house, as has been explained, was built against a shallow cave of the mountains; but, owing to the irregularity of the hollow, part of the rear wall was of solid masonry, while the other part was formed by the cliff itself. Kāra had never before paid much attention to that fact, but now it struck him as very evident that the masonry had been constructed to shut off an orifice too deep or too irregular to be utilized as part of the dwelling. Otherwise, the continuation of the cliff would have rendered a wall unnecessary. The stones were of large size and were built up and cemented as far as the overhanging rock that formed the greater portion of the roof.

The Egyptian’s eyes rested upon the third layer of these stones, and he counted from the corner to the seventh stone. In appearance this was not different from the others; but Hatatcha’s directions had been exact, and she knew.

He walked to the spot and pressed hard against the right edge of the stone. It moved, and gradually swung inward, the left edge being supported by solid pivots of bronze at the top and bottom.

The opening disclosed was about four feet long by three feet in height, and Kāra at once crept through it, holding his lamp extended before him. Yes; his surmise had been correct—a low, but deep and irregular cavern was behind the wall.

His first care was to close up the entrance by pressing the block of stone back to its former position. There was a bronze handle on the inner side that would permit him to open it again easily.

The cavern felt damp and cool, and when he raised his lamp he saw some deep fissures leading far under the mountain. He selected the second from the left of these rifts and cautiously made his way along the rough floor. At first it seemed that he had made a mistake, for this way was less promising than several of the others; but when he stopped and thought upon Hatatcha’s directions, he knew that he was right.

The rift made a sudden turn and sank downward; but the rocks under his feet were now more even and the way became easier to traverse. A hundred paces farther, the passage ended abruptly in a sharp point where the rock had originally split.

The young Egyptian walked to the extreme end and then carefully measured three paces back again. Raising his lamp, he examined the right wall of the tunnel closely. It contained many irregular cracks and hollows, but one indentation seemed, on observation, to be surrounded by a tiny circle of black, or a color darker than the other portions of the rock.

Kāra uttered an ejaculation of pleasure. He had feared he might not find this spot, in spite of his grandmother’s assurances that it was plain to keen eyes.

Drawing a short, pointed dagger from the folds of his burnous—a weapon he had found in the crypt beside the arch of the living-room—the Egyptian thrust it into the orifice of the rock and pushed until it had sunk in to the very hilt. Then he turned the handle, and a sharp “click” was audible.