Rador drew from his girdle a ring and held it out to the first dwarf. He examined it, handed it to the one beside him, and not until each had inspected the ring did they lower their curious weapons; containers of that terrific energy they called the Keth, I thought; and later was to know that I had been right.

We stepped out; the doors closed behind us. The place was weird enough. Its pave was a greenish-blue stone resembling lapis lazuli. On each side were high pedestals holding carved figures of the same material. There were perhaps a score of these, but in the mistiness I could not make out their outlines. A droning, rushing roar beat upon our ears; filled the whole cavern.

“I smell the sea,” said Larry suddenly.

The roaring became deep-toned, clamorous, and close in front of us a rift opened. Twenty feet in width, it cut the cavern floor and vanished into the blue mist on each side. The cleft was spanned by one solid slab of rock not more than two yards wide. It had neither railing nor other protection.