reat value as to be utterly beyond computation.

"Without doubt," I answered, stooping and picking up several jewelled
trinkets, girdles and other ornaments, each bearing the sacred reptile or
the vampire crest of royalty. "The recovery of these will, at least repay
thy nation for the expedition sent against their enemy. Retain possession
of the Rock Diadem of Mo, for thou hast discovered it, and with thine own
hands shalt thou deliver it into the possession of the ruler who loveth
thee."

Then, carefully wrapping the ancient badge of regal dignity in a piece of
hide and binding it securely with wire as the carriers' loads had been, I
gave it back to her. In half an hour we had completed our examination of
the wondrous accumulation of treasure, finding among it many quaint and
extraordinary ornaments, some no doubt dating from the earlier days of
the foundation of the mysterious isolated kingdom, and others
manufactured during recent centuries. The gems were unique in size and
character. Truly the thieves in the employ of the Arab chief had taken
care to secure the most valuable portion of the royal jewels and leave
behind only those of least worth.

With the secret of their concealment in our possession we were both full
of eagerness to get back to the light of day and take steps for their
removal, yet I confess that the mystery of what was contained behind
those strange plates of iron puzzled me.

Leaving Liola to continue her inspection of our discovered treasures, I
crossed to the wall and examined one of the plates again, trying with
both hands to force it out, but being compelled to relinquish the attempt
as hopeless. I was about to give up all idea of discovering how they
might be opened, when Liola suddenly uttered an exclamation, and in
turning to glance at her, the flame of the lamp I held came into contact
with the wall close to the plate that had defied my exertions to remove
it.

In an instant a bright flash ran around the chamber, lighting it up as
bright as day; a puff of grey smoke was belched in our faces, and a
report like thunder deafened us.

An explosion had occurred, great pieces of rock and other _debris_ being
flung in all directions.

Its terrific force hurled me heavily against the wall, while Liola was
flung face downward upon the pile of jewels. Fortunately, neither of us
sustained any injury beyond a few bruises, but when I had assisted her to
rise, and gazed around, I was amazed to