“It’s certain this tunnel wasn’t dug for nothing,” Gil said, after they had walked at an ordinary pace for at least twenty minutes without having seen anything but the coral walls. “People wouldn’t spend much time on such work simply for fun, and it must have required many days to hew out such an amount of rock.”

“I reckon we’ve come to the end,” Jenkins replied, as the passage began to trend upward at a very decided inclination, and a moment later he stopped at what appeared to be the termination of the tunnel.

Before them was apparently a solid wall, but, as the light was thrown on it, Gil could see a crevice, very narrow and nearly filled with dust, at the side and bottom.

“It’s a door!” he cried, “and behind it is the gold!”

Jenkins handed the torch to Nelse, and threw his whole weight against the rock.

It yielded slightly, giving an opening not more than half an inch wide, through which warm air and a glow as of a fire entered the tunnel.

Quickly, and without speaking, the mate extinguished the torch, and, to the astonishment of all, the sound of voices could be heard, indistinctly, it is true, but sufficiently to make it positive human beings were conversing at no very great distance from the aperture.

This was a conclusion to the tour of discovery upon which the explorers had not reckoned, and for several moments all stood in silent dismay, not knowing what course to pursue.

Then Jenkins tried to close the stone door, but in vain. It was perfectly smooth, and he could gain no hold upon it.

But few seconds were spent on the useless work.