ountain and the
airport tower. Then, with that as his base line, it was easy to draw two
lines at the correct angles from each of the points. The transit's
position was where the two lines intersected.

By the time the scientist had finished, it was nearly one o'clock. The
three walked to the detonator. "Pull the handle up," Zircon directed.
Rick did so. "I'll count down from ten seconds. Push down on zero."

It was like the countdown for a rocket firing, Rick thought. Zircon
called out the time starting at one minute, then called off the last ten
seconds. As he reached zero, Rick pushed the handle home.

The dynamite went off with a roar that sent leaves and dirt flying, and
Rick felt the shock wave slam against his ears with stunning force.

"Open your mouth next time," Zircon said. "I forgot to warn you." He was
already reeling in the wire. "Let's get going. One mile farther on for
the next shot."

At the next station the same procedure was repeated, but before it was
time, there was a far-off explosion. Zircon looked at his watch. "Brad
Connel. Right on time." In another fifteen minutes there was an even
more distant sound as David Riddle's first shot went off. They ate their
lunch and listened to the echo off the mountain.

Zircon and the boys were ready when their time came. Location this time
had been made on sightings toward the mountain, and a flagpole at Cape
San Souci on the western side of the island.

The road petered out and they were forced to go cross-country to reach
the third shot station. Fortunately, Brad Connel had left a path of
crushed vegetation, so it was only necessary to follow where he had led.

After the third shot, the three collected their equipment and drove back
to the hotel.

They were the first back. All three were sticky from the heat, and
somewhat insect bitten. By unanimous consent they headed for the
showers.

Rick dressed except for his shoes, then stretched out on his bed. He
wondered what the day's work would show. The memory of the earthquake
was still fresh, and he was anxious to see if it had come from rising
magma far below, or from some other source. He had a mental image of
white-hot rock rising sluggishly, melting a path to the surface. Now and
then the magma struck water, or gas-producing minerals, and then there
was a tightly held explosion that made the earth shudder.

Well, it was probably like that, from what he had read about volcanic
action. Anyway, he