No exit of any sort rewarded them here either, and hardly daring to look each other in the face, from fear of what they might see there, they returned to the main chamber, into which Drake had fallen headlong in the first instance. Here they could still hear the distant shouts and trampling of the pirates, who were evidently moving about in the chamber directly overhead, continuing the search for their prey; but even the thought that they were safe from those barbarous savages was now hardly sufficient to cheer them. It would have been almost better to have met death in the open, fighting, than to be compelled to watch his slow approach in this dismal place, far below the level of the ground.
Unable to remain still, Frobisher again most carefully examined the inside of the secret door in search of a hidden spring, but no sign of it could he discover. It seemed evident that, unless the door were actually propped open by the person entering the vault, there was no getting back by that way; and Frobisher could not help thinking that surely some other exit must have been provided. The people accustomed to using the vault could not be expected always to remember to prop the door open when they entered; and it did not seem reasonable to suppose that the place had been so constructed that a mere lapse of memory would be tantamount to a person signing his own death-warrant. An emergency exit must have been made for use in case the main door became closed accidentally or otherwise; but the question was, where was it situated?
Drake suggested that there must undoubtedly be an opening somewhere, because the air in the vault was comparatively pure and fresh; at least it had not the dead, stale, stuffy smell of air confined in a hermetically-sealed chamber. But Frobisher pointed out that the door by which they had entered, although an excellent fit, did not butt up against the jambs so closely as to exclude the air altogether; yet he acknowledged that the air in the vault certainly seemed sweeter than might have been expected, had the main door been the only channel through which it could filter in.
Under the stimulus of the new glimmer of hope thus caught, every corridor was once more explored, even more closely than before, but with no other result than that Frobisher completely satisfied himself that there was most certainly no exit from any of the passages. Even a concealed door, opened by a spring, could hardly have evaded the close scrutiny of the two men; and it became more and more apparent that they had been caught in a trap from which there was no escape. Both were feeling famished for want of food, and were parched with thirst; and Frobisher could not help wondering how long the agony of death from starvation and thirst would be prolonged before blessed unconsciousness came to their relief.
Suddenly—they had both been sitting dejectedly on the floor—Frobisher jumped to his feet.
“Look here, Drake,” he exclaimed, “there is just one place that we never thought of searching, and that’s the treasure chamber itself. We were too deeply interested in the valuables we found to think of looking for an exit in there. Who knows?—the very thing we are hunting for may be in there all the time.”
The two men fairly raced down the passage leading to the chamber, opened the latch, with all due caution, and re-entered the vault. At first sight there appeared to be no semblance of a second door, and their hopes dropped to zero once more. Then Drake proposed that, as a last chance, they should remove the chests to the centre of the room and see whether, possibly, there might be a door concealed behind any of them. They set to work feverishly, and in doing so spilled the jewels and coins in heaps on the floor. But what did that matter? Unless they found a way of escape from their prison, jewels and coin would be of far less value to them than a loaf of bread and a jar of water.
Then, at the very end, when their hopes were practically extinguished, the last chests removed disclosed a little oaken door set into the wall, not more than four feet high by three feet broad. Drake was about to open it impulsively when Frobisher restrained him. He did not want either of them to be killed on the very threshold of success by some other hidden and fiendishly ingenious piece of mechanism. But when cautiously opened with the aid of one of the sticks, nothing happened in this instance, and they crawled safely through into another passage, being careful to close the door behind them.
This passage looked a good deal more promising, there being no less than four other corridors branching off it at right angles, each, curiously enough, leading away to the left. But they determined to go straight ahead in the first instance, exploring the corridors afterwards, if not successful in their present direction. They traversed so long a distance in a perfectly straight line, the ground rising gently all the way, that they soon became convinced that they were at last on the right track, as the passage must, some distance back, have passed from under the foundations of the palace itself, and be leading, undoubtedly, to some exit at a considerable distance from the building. It seemed probable that it might have been constructed with a view to providing a means of escape, should the palace ever be attacked and stormed.
That they were correct in their surmise was proved shortly afterward when, a little distance ahead, Frobisher caught sight of a pin-hole of light. This presently resolved itself into sunlight shining through the keyhole of another door; and they realised that, since it was now broad daylight, they must have spent several hours in Genghiz Khan’s treasure-house. The door did not open with a handle, as the others had done, and there was no key hanging handily on the wall, as there had been when Frobisher escaped out of the pirate fortress; so that, after all, there was still a rather formidable obstacle to be overcome before they could actually stand in the blessed light of day again.