of two hundred and fifty millions of people. These would all be in the
boxes on this side."

The boys opened their eyes at the magnitude of the figures.

"An orchestra of one hundred million pieces and a chorus of a hundred
and fifty million voices could be placed comfortably on the opposite
side. Can you conceive of such a scene? What do you think of it?"

"I---I think," stammered Chunky, "that I'd like to be in the box office
of that show---holding on to the ticket money."

Without appearing to have heard Stacy Brown's flippant reply, Professor
Zepplin began again.

"Now that you are about to explore this fairy land it is well that you
be informed in advance as to what it is. The river which you see down
there is the Colorado. As perhaps some of you, who have studied your
geography seriously, may know, the river is formed in southern Utah by
the confluence of the Green and Grand, intersecting the north-western
corner of Arizona it becomes the eastern boundary of Nevada and
California, flowing southward until it reaches the Gulf of California."

"Yes, sir," said the boys politely, filling in a brief pause.

"That river drains a territory of some three hundred thousand square
miles, and from its source is two thousand miles long. This gorge is
slightly more than two hundred miles long. Am I correct in my
figures, Mr. Nance?" demanded the Professor, turning to Dad, a
"contradict-me-at-your-peril" expression on his face.