Outside was a low embankment, then the dark waste of the morass that girded Shingtse-lunpo. To the west, in the thin veil of rain, was a shapeless blur that Trent imagined was Amber Bridge. The Great Magician shut the gate and led the way down the embankment. The ground was not soggy, as Trent expected, and, straining his eyes, he saw the reason. They were following a barely visible road through the rushes.
Toward the shapeless blur they moved. As they drew nearer it became apparent that it was not Amber Bridge, but a pile of broken stone—a remnant of the old outer-fortifications—in the middle of the swamp-belt. When they reached the mass of masonry Trent saw that it was a portion of a broken wall, rising above nearly obliterated flagstones that formed the floor of what had once been a room, or a tunnel, under a mighty rampart—a wall that was hollowed and whose roof had fallen in. The passage thus formed was not more than three feet in width and ran for several yards before it ended in a cul-de-sac.
Into the narrow space between the walls Trent and Sarojini Nanjee followed the Great Magician. It was damp and smelled of freshly-turned earth. A few feet from the entrance the Tibetan paused and grunted a word to Sarojini. Instantly a saber of light smote the darkness, a ray from a very modern electric torch in the woman's hand. The Great Magician took the light from her, flashing it into the cul-de-sac and upon a small stone stairway that plunged into grim depths.
Down into the bowels of the earth it carried them, into a rectangular crypt. Blocks of masonry had been torn away from one side of the wall and an irregular aperture gaped blackly. Trent observed that the stones had not been removed recently, for they were wedged in mud and grown with fungi.
Through the rent in the crypt they passed, entering a tunnel that bored downward at a gradual incline. The torchlight wavered upon damp, ancient walls; upon several inches of water in the bottom of the passage. Cold, earthy odors fouled the air. Before they had proceeded far, loose rocks rattled underfoot, and Trent, glancing down, saw that he was treading upon chips and small particles of stone. White dust streaked the muddy water. This prepared him for the pile of shattered rock that appeared suddenly ahead, heaped at one side of a crude doorway. All of which attested to the fact that the passage had at one time been sealed, but very recently opened—and by men who were not masons.
The tunnel continued its gradual downward course for what Trent calculated was at least a mile. If he judged aright they must be somewhere near the middle of the city. Suddenly the subterranean corridor made a series of turns, then sloped upward, running straight after that and bringing them at length into a crypt similar to the one beneath the swamp-ruins. The smell of oil hung in the air, and Trent identified it with the iron-bound door at one side. He was surprised to see that its lock was very modern. (From some shop in Gyangtse or Darjeeling—thus he conjectured irrelevantly.) The Great Magician fumbled at the formidable portal, and, following a grating noise, it swung out soundlessly on well-oiled hinges. Yellow light impinged upon the darkness of a stairway, on the bottom step of which rested a brass lamp.
The priest lighted the lamp, and Sarojini Nanjee, slipping her hand into Trent's, led the Englishman through the door and up the stairway. Looking back, Trent saw the Great Magician sink cross-legged upon the floor; then the picture was shut out as they climbed higher into gloom. Near the top Sarojini halted and directed the light upward. It swept a square of stone at the very head of the stairs; the lines where it fitted into place were scarcely visible.
"You will have to lift the stone," Sarojini told him, stepping aside.
He mounted the few remaining stairs and stooped in the meager space at the top, pressing hands and shoulders against the square of stone. Warm blood rushed into his stained cheeks as he slowly drew erect, lifting the stone from place and letting it fall noisily upon the floor above. The space into which the rock fitted was perhaps three yards around, widening out at the top. Trent's head and shoulders projected from the aperture into blackness that was more intense because of the light from which he had emerged.
"Pull yourself up," directed Sarojini. "Then I will give you the light."