The boys promised and so did the Professor, and both men knew the lads would keep their word, for by this time they held that stream in wholesome respect.

Chunky, after the guide and Tad had left, perched himself on the point of a rock where he lifted up his voice in “Where the Silvery Colorado Wends Its Way,” Ned Rector occupying his time by shying rocks at the singer, but Chunky finished his song and had gotten half way through it a second time before one of Ned’s missiles reached him.  That put an end to the song and brought on a rough and tumble fight in which Ned and Stacy were the sole participants.  Chunky, of course, got the worst of it.  The two combatants locked arms and strolled away down the river bank after Chunky had been sufficiently punished for trying to sing.

Night in the canyon was an experience.  The roaring of the river which no longer could be seen was almost terrifying.  Then, too, a strange weird moaning sounded all about them.  Dad, who had returned, explained that it was supposed to be the wind.  He confided to Tad that it was the spirit of the Canyon uttering its warning.

“Warning of what?”

“I don’t know.  Maybe a storm.  But you can believe something’s going to come off, kid,” answered Nance with emphasis.

Something did come off.  Tad and Nance had fetched the blankets of the party back with them, together with two large bundles of wood for the camp fire, which materials they had let down from point to point at the end of their ropes.  Tad had learned always to carry his lasso at his belt.  It was the most useful part of his equipment.  He had gotten the other boys into the habit of doing the same.  Rifles had been left in the camp above, as they were a burden in climbing down the rocks.  But all hands carried their heavy revolvers.

A very comfortable camping place was located Under an overhanging shelf of rock, the camp fire just outside lighting up the chamber in a most cheerful manner.  There after supper the party sat listening to Dad’s stories of the Canyon during some of his thirty years’ experience with it.

The wind was plainly rising.  It drew the flames of the fire first in one direction, then in another.  Nance regarded the signs questioningly.  After a little he got up and strolled out to the edge of the roaring river.  Tad and Chunky followed him.

“We are going to have a storm,” said Dad.

“A heavy one?” asked Tad.

“A regular hummer!”

“Rain?”

“Everything.  The whole thing.  I’m sorry now that we didn’t go back up the trail, but maybe we’d never got up before we were caught.  However, we’re pretty safe down here, unless-----”

“Unless what?” piped Chunky.

“Unless we get wet,” answered Nance, though Tad knew that was not what was in the guide’s mind.

Just as they were turning back to the camp there came an explosion that seemed as if the walls of the Canyon had been rent in twain.  Chunky uttered a yell and leaped straight up into the air.  Tad took firm hold of the fat boy’s arm.