and again the torpedoes replied, this time
all clear. The hush of a hundred voices, the silence of the bars and
shovels and picks gave back to the chill canyon its loneliness, and the
roar of the river rose undisturbed to the brooding night.

On the ledge Glover was alone. The final detail he was taking into his
own hands. The few that could still command the point saw the red
light moving, and beside it a figure vaguely outlined making its way.
When the red light paused, a spark could be seen, a sputtering blaze
would run slowly from it, hesitate, flare and die. Another and another
of the fuses were touched and passed. With quickening steps tier after
tier was covered, until those looking saw the red light flung at last
into the air. It circled high between the canyon walls in its flight
and dropped like a rocket into the Rat. A muffled report from the
lower tier was followed by a heavier and still a heavier one above. A
creeping pang shot the heart of the granite, a dreadful awakening was
upon it.

From the tier of the upmost holes came at length the terrific burst of
the heavy mines. The travail of an awful instant followed, the face of
the spur parted from its side, toppled an instant in the confusion of
its rending and with an appalling crash fell upon the river below.

With the fragments still tumbling, the nearest men started with a cheer
from their concealment. Smoke rolling white and sullen upward obscured
the moon, and the canyon air, salt and sick with gases, poured over the
high point on which the Pittsburgers stood. Below, torches were
shooting like fireflies out of the rock. From every vantage point
headlights flashed one after another unhooded on the scene, and the
song of the river mingled again with the calling of the foremen.

"That ends the fireworks," remarked Bucks to those about him. "Let us
watch a moment for Mr. Glover's signal to me. As soon as he inspects
he is to show signals on the Cat's Paw, and if it is a success we will
return at once to Sleepy Cat."

"And by the way, Mr. Bucks, I shall expect you and Mr. Glover up to the
car for my game supper. Have you arranged for him to come?"

"I have, Mrs. Whitney, thank you."

"Oh, see those pretty red lights over there now. What are they?" asked
Louise, who stood with Allen Harrison.

"The signals," exclaimed Bucks. "Three fusees. Good for Glover; that
means success. Shall we go?"

When the sightseers made their way