we climbed the oval stairway and emerged on the platform under the
cupola the dawn was just about to break. The Gray Mahatma raised the
stone lid with an ease that betrayed unsuspected strength and dropped it
into place, where it fitted so exactly that no one ignorant of the
secret would ever have guessed the existence of a hidden stairway.

Swinging his lantern the Mahatma led into the temple, where the enormous
idols loomed in quivering shadow, and made straight for the biggest one
of all--the four-headed one that faced the marble screen. I thought he
was going to bow down and worship it. He actually did go down on hands
and knees, and I turned to King in amazement, thus missing my chance to
see what he was really up to.

So I don't know how he managed it; but suddenly the whole lower part of
the idol, including the thighs, swung outward and disclosed a dark
passage, into which he led us, and the stone swung back into place at
our backs as if balanced by weights.

At the far end the Mahatma led into a square-mouthed tunnel, darker if
that were possible than the vaulted gloom we had left, and as we entered
in single file I thought I heard the splashing of water underneath.

About a minute after that the Mahatma stopped and let King draw abreast;
then, continuing to swing the lantern he started forward again. I don't
know whether it was fear, intuition, or just curiosity that made me
wonder why he should change the formation in that way, but quite
absurdly I deduced that he wished King to walk into a trap. It was that
that saved me.

"Look out, King!" I warned.

Exactly as I spoke I set my foot on a yielding stone trap-door--felt a
blast of cool air--and heard water unmistakably. The air brought a
stagnant smell with it. I slid forward and downward, but sprang
simultaneously, managing to get my fingers on the edge of the stone in
front. But the balanced trap-door, resuming its equilibrium, caught me
on the back of the head, half-stunning me, and in another second I would
have gone down into the dark among the alligators. I just had enough
consciousness left to realize that I was hanging over the covered end of
the alligator tank.

But the faint outer circle of light cast by the Mahatma's lantern just
reached me, and as King turned his head to acknowledge my warning he saw
me fall. He sprang back, and seized my wrists, just as my fingers began
slipping on the smooth stone; but my weight was almost too much for him