hen
the great stone cross-piece, weighing several tons, that was set as
a transom above the tall door of our room, dislodged itself, and fell
quite gently into the doorway, which it completely blocked.

Other rocks fell also at a distance, making a great noise, and somehow
I found myself on the ground, my stool had slid away from me. Next
followed a muffled, awful roar, and with it came a blast of wind blowing
where wind never blew before since the beginning of the world, that with
a terrible wailing howled itself to silence in the thousand recesses of
the cave city. As it passed our lamps went out. Lastly, quite a minute
later I should think, there was a thud, as though something of enormous
weight had fallen on the surface of the earth far above us.

Then all was as it had been; all was darkness and utter quietude.

"Well, that's over," said Oliver, in a strained voice which sounded very
small and far away through that thick darkness; "all over for good or
ill. I needn't have been anxious; the first battery was strong enough,
for I felt the mine spring as I touched the second. I wonder," he went
on, as though speaking to himself, "what amount of damage nearly a ton
and a half of that awful azo-imide compound has done to the old sphinx.
According to my calculations it ought to have been enough to break the
thing up, if we could have spread the charge more. But, as it is, I
am by no means certain. It may only have driven a hole in its bulk,
especially if there were hollows through which the gases could run.
Well, with luck, we may know more about it later. Strike a match, Adams,
and light those lamps. Why, what's that? Listen!"

As he spoke, from somewhere came a series of tiny noises, that,
though they were so faint and small, suggested rifles fired at a great
distance. Crack, crack, crack! went the infinitesimal noises.

I groped about, and finding the receiver of the field telephone, set
it to my ear. In an instant all grew plain to me. Guns were being fired
near the other end of the wire, and the transmitter was sending us the
sound of them. Very faintly but with distinctness I could hear Higgs's
high voice saying, "Look out, Sergeant, there's another rush coming!"
and Quick answering, "Shoot low, Professor; for the Lord's sake shoot
low. You are empty, sir. Load up, load up! Here's a clip of cartridges.
Don't fire too fast. Ah! that devil got me, but I've got him; he'll
never throw another spear."

"They are