The way led back down the inclined gallery to a point where another door now stood open, then on down until finally the passage leveled out into a long, straight tunnel.

This they traversed for fully a mile, entering at length a large, square chamber where for a moment they paused.

“I judge we are now at the base of the large pyramid,” the professor voiced in an undertone. “It would naturally be the abode of the high priests.”

“But what do you suppose they want with us?” asked Diane.

“That I am not disposed to conjecture,” was her father’s reply.

But the note of anxiety in his voice was not lost on Diane, nor on Larry, who pressed her hand reassuringly.

Now their captors led them from the room through a small door opening on another inclined gallery, whose turns they followed until all were out of breath from the climb.

It ended abruptly on a short, level corridor with apertures to left and right.

Into the latter they were led, finding themselves in a grotesquely furnished room, lit dimly by phosphorescent lamps.

Swiftly the leader addressed Professor Stevens. Then all withdrew. The aperture was closed by a sliding block of stone.