out of this precious predicament."

But that they would ever get out of it at all seemed to both of them
now in the highest degree improbable. Cyril, by reason, Elma, by
instinct, argued out the whole situation at once, and correctly.
There had been much rain lately. The sandstone was water-logged. It
had caved in bodily, before them and behind them. A little isthmus
of archway still held out in isolation just above their heads. At
any moment that isthmus might give way too, and, falling on their
carriage, might crush them beneath its weight. Their lives depended
upon the continued resisting power of some fifteen yards or so of
dislocated masonry.

Appalled at the thought, Cyril moved from his place for a minute,
and went forward to examine the fallen block in front. Then he
paced his way back with groping steps to the equally ruinous mass
behind them. Elma's eyes, growing gradually accustomed to the
darkness and the faint glimmer of the oil lamps, followed his
action with vague and tearful interest.

"If the roof doesn't give way," he said calmly at last, when he
returned once more to her, "and if we can only let them know we're
alive in the tunnel, they may possibly dig us out before we choke.
There's air enough here for eighteen hours for us."

He spoke very quietly and reassuringly, as if being shut up in a
fallen tunnel between two masses of earth were a matter that needn't
cause one the slightest uneasiness; but his words suggested to
Elma's mind a fresh and hitherto unthought-of danger.