ther
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.

* * * * *

For a moment they stood there silent, straining their eyes in the
gloom to detect the details of their surroundings, which included
several curious chairs and a number of mattings strewn on the tiled
floor.

"What did he say?" asked Diane at length, in a tremulous voice.

"He said we will remain here for the night," her father replied, "and
will be taken before the high priests at dawn."

"At dawn!" exclaimed Larry. "How the deuce do they know when it is
dawn, down here?"

"By their calendars, which they have kept accurately," was the answer.
"But there are many other questions you must both want to ask, so I
shall anticipate them by telling you now what I have been able to
learn. Suppose we first sit down, however. I for one am weary."

Whereupon they drew up three of those curious chairs of some heavy
wood carved with the hideous figures of this strange people's ancient
gods, and Professor Stevens began.

* * * * *

Their sunken empire, as he had surmised, had indeed been the great
island of Antillia and a colony of Atlantis. A series of earthquakes
and tidal waves such as engulfed their homeland ages before had sent
it down, and the estimated archaeological date of the final
submergence--namely, 200 B. C.--was approximately correct.

But long be