hand in mute appeal
to heaven, and at the instant there is a flash, a sharp report not
thirty yards away, an angry spat as the leaden missile strikes the
shelving top of his parapet and goes humming across the gorge, a
stifled shriek from Ruth looking fearfully up from below, an Irish
oath from Walsh as he whirls about to answer the shot, and Drummond
can barely repress a little gasp.

"Narrow squeak that, Walsh! That devil has crawled close up on us. Can
you see him?"

"Begad, sir, I can see nothing at all but rocks, rocks, rocks. How can
a man fight anyway agin' human beings that crawl like snakes?"

Zip! Another shot close at hand, too, and from another unseen foe. The
first came from somewhere among the bowlders down to the southeast,
and this second whizzed from across the canon. A little puff of blue
smoke is floating up from among the rocks fifty yards or so to the
north of the narrow slit.

Crouching lower, Drummond calls across to Costigan, posted as the
easternmost of the two men on the opposite side,--

"That fellow is nearest you, corporal; can you see nothing of him?"

"Nothing, sir; I was looking that way, too, when he fired. Not even
the muzzle of his gun showed."

This is serious business. If one Indian or two can find it so easy to
creep around them and, armed only with their old muzzle-loading guns,
send frequent shots that reach the besieged "in reverse," what can be
hoped when the whole band gathers and every rock on every side
shelters a hostile Apache? From the first Drummond has feared that
however effective might be these defences against the open attack of
white men, they are ill adapted to protect the defenders against the
fire of Indians who can climb like squirrels or crawl or squirm
through any chink or crevice like so many snakes.

Another shot! Another bullet flattens itself on the rock close to his
right shoulder and then drops into the dust by his knee. It comes from
farther up the cliff,--perhaps two hundred yards away among those
stunted cedars,--but shudderingly close. Costigan and the other men
glance anxiously over their shoulders at the point where their young
commander and Walsh are crouching. They are not yet subjected to a
fire from the rear, these others. The lookout, the signal-station, as
it might be called, is the highest point and most exposed about the
position.

"For God's sake, lieutenant," cries the corporal, "don't stay there.
They've got your range on two