e fellows would have been scared just stiff, and couldn't have
thrown out a hand to save a chum. But look here, Frank, you don't
imagine that thing was done on purpose, do you?"

Frank looked at his companion, with a wrinkle on his forehead.

"I don't want to think anybody could be so mean and low as to want to
hurt boys who'd never done them any harm," he said; "but all the same I
seem to have an idea that I got a glimpse of a man's arm when that rock
started to drop."

"Whew! you give me a cold chill, Frank," muttered Bob, gazing helplessly
upward toward the spot from which the descending rock had started on its
riotous tumble.

"Yes, and I hope I was mistaken," Frank went on. "I don't see anything
up there now; and perhaps it was only a delusion. All these bright
colors affect the eyes, you see. Then, again, it might have been some
goat jumping, that started that rock on its downward plunge."

"But you didn't see any goat, Frank, did you?" Bob asked, anxiously.

"No, I didn't," admitted the other; "but then there may be a shelf up
there, and any animal on it would be hidden from the eyes of those right
below."

They passed on; but more than once Bob craned his neck in the endeavor
to look up to that spot, from whence the loose rock had plunged. He
could not get it out of his head that foes were hovering about, who
thought so little of human life that they would conspire to accomplish a
death if possible.

The day passed without any further peril confronting them. Charley Moi
seemed to fill the bill as a guide, very well. He also knew the
different points of interest, and chattered away like a magpie or a
monkey as they kept pushing on.

Bob became curious to know just how the Chinaman could tell about so
many things when they were now above the trails used ordinarily by
tourists, who gave two or three days to seeing the Grand Canyon, and
then rushed away, thinking they had exhausted its wonders, when in fact
they had barely seen them.

He put the question to Charley Moi, and when the smiling-faced Chinaman
replied, Frank caught his breath.

"That easy, bloss," said Charley, nodding. "Happen this way. Long time
black me 'gage with sahib, like one know out in Canton. Think have samee
big joss some bit up here in canlon. Me to bling grub to certain place
evly two month. Him give me list what buy, and put cash in hand. Know
can trust Chinaman ebery time. Many time now me do this; so know how
make trail up-r