'm going to get on top of the pedestal."

He managed to scramble up by stepping on and clinging to various
ornamental projections, and soon gained the flat place where the big
golden statue had rested. But he saw at a glance that it was as
smooth as a billiard table.

"Nothing here!" he called down to Ned.

"Then how do you suppose the gate closed down when the statue was
pulled off?" asked Ned.

"It must have been because of the disturbance of the equilibrium, or
due to a change of weight. Probably this pedestal rests on a
platform, like the platform of a large scale. Its weight, with that
of the statue, rested on certain concealed levers, and held the
stone up out of sight in the roof of the tunnel. When I yanked down
the statue I made the weight uneven, and the stone fell, and there
doesn't seem to be any way of putting the weight back again."

"No, we never could get the statue back on the pedestal," said Ned.
"But maybe there's some mechanism at the stone gate, or near it,
like the black knob which turned off the water. We may be able to
work that and raise the big stone slab."

"It's the only thing to try, as long as we haven't dynamite to blast
it," agreed Tom. "Come on, we'll take a look."

They went back to where the rock closed the tunnel, but a long and
frantic search failed to show the least projection, lever, handle or
any other thing, that could be moved.

"What in the world do you suppose those ancients made such a
terrible contrivance for?" Ned wanted to know.

"Well, if we could read the warning on the statue we might know,"
replied Mr. Damon. "That probably says that whoever disturbs the
status will close up the golden city forever."

"Maybe there's another way out--or in," suggested Tom hopefully. "We
didn't look for that. It must be our next move. We must not let a
single chance go by. We'll look for some way of getting out, at the
far end of this underground city."

Filled with gloomy and foreboding thoughts, they walked away from
the stone barrier. To search for another means of egress would take
some time, and the same fear came to all of them--could they live
that long?

"It was a queer thing, to make that statue hollow," mused Ned as he
walked between Mr. Damon and Tom. "I wonder why it was done, when
all the others are solid gold?"

"Maybe they found they couldn't melt up, and cast in a mould, enough
gold to make a solid statue that size," suggested Mr. Damon. "Then,
too, ther