u talk to me
about nerve."

"There come the others."

The Professor, the guide and the other boys walked slowly up to them at
this juncture. Chunky expected that Ned would make fun of him. Ned did
nothing of the sort. Both Ned and Walter were solemn and their faces
were drawn. They sighed as if they had just awakened from a deep sleep.

"What do you think of it, Professor?" asked Tad, looking up.

"Words fail me."

"I must have another look," announced Butler.

He walked straight to the edge of the rim, then lying flat on his
stomach, head out over the chasm, he gazed down into the terrible abyss.

Jim Nance nodded approvingly.

"He's going to love it just the same as I do." The old man's heart
warmed toward Tad Butler in that moment, when Tad, all alone, sought a
closer acquaintance with the mystery of the great gash. After a time
the others walked back, Dad taking Chunky by the nape of the neck.
Perhaps it was the method of approach, or else Chunky, having had his
fright, had been cured. At least this time he felt no fear. He was
lost in wonder.

"Buck up now!" urged the guide.

"I am bucked. Leggo my neck. I won't make a fool of myself this time,
I promise you."

"You can't blame him," said Tad, rising from his perilous position and
walking calmly back to them. "I nearly got them myself."

"Got what?" demanded Stacy.

"The jiggers."

"That's it. That describes it."

Professor Zepplin, who had informed himself before starting out, now
turned suddenly upon them.

"He's going to give us a lecture. Listen," whispered Tad.

"Young gentlemen, you have, perhaps, little idea of the vastness of that
upon which you are now gazing."

"We know it is the biggest thing in the world, Professor," said Ned.

"Imagine, if you can," continued the Professor, without heeding the
interruption, "that this amphitheatre is a real theatre. Allowing
twice as much room as is given for the seat of each person in the most
comfortable theatre in the world, and you could seat here an audience
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 t