ace. Only a small
group of scientists remained, their helicopter standing by. They checked
out the radio firing unit, threw switches according to their check list,
then announced:

"We're ready!"

CHAPTER XIX

The Old One Yields

Rick banked the Sky Wagon over the fleet. Scotty, in the front passenger
seat, had the camera ready. Hartson Brant, in the rear seat, had a
motion-picture camera poised. Governor Montoya, the fourth in the party,
even had his personal camera along.

Their cameras were not the only ones. Nearly every ship had its official
photographers, and there were photography planes in the air.

Directly under the Sky Wagon now was a U. S. destroyer. Aboard her was
the nuclear firing party from Los Alamos Scientific Laboratory, and the
UN Observer Group. On other ships of the fleet were the representatives
of the interested nations and the Seabees.

Rick turned up the volume of his plane radio. By agreement, the
countdown was to be broadcast to all aircraft over one of the airport
frequencies.

"Thirty seconds!" the voice said.

"Won't we need dark glasses?" Scotty asked.

"No," Hartson Brant replied. "The nuclear fireball won't emerge. If it
gets a little too bright, squint and turn your head."

"How long after the nuclear shot will the volcano go?" Rick asked.

"We don't know. Anywhere from seconds to hours. It depends on how much
of a path the nuclear shot cracks."

"Ten seconds!"

Rick made sure they had a good view of El Viejo's western slope, and
held the plane on course.

"Five, four, three, two, one ...

"Zero!"

There was an instant of quiet, then dust spurted from the deep hole,
followed by billowing clouds of pulverized rock. Down below, the earth
heaved as though from another earthquake, and a line of waves appeared,
running from shore outward!

The dust settled slowly, hanging in the air like a great gray ball.

The nuclear explosion, deep underground, had gone off.

"Now what?" Rick wondered.

Hartson Brant said quietly, "We may have to wait a while."

"That explosion sure didn't look like the pictures I've seen of shots in
Nevada," Rick told him.

"No, Rick. This was too far underground. They've had those in Nevada,
too, but the pictures don't get much publicity because they're not
spectacular."

Far below, where the end of the big hole had been, the huge chamber
blown by the atomic explosion was white-hot with trapped heat and
radioactivity. Below the