co reported that the bomb had been dismantled. Rip went to it and
examined the raw plutonium, being careful to keep the pieces widely
separated.

This particular bomb design used five pieces of plutonium which were
driven together to form a ball. Rip made a quick estimate. Two were
enough to form a critical mass. He would use two to blast into the sun
and three to blast out again. He would need the extra kick.

There was only one trouble. The pieces were wedge shaped. They would have
to be mounted in thorium in order to keep them rigid. Only Kemp could do
that. They had no cutting tool but the torch.

Santos appeared, carrying a rocket head under each arm. They had wires
wound around them, ready to be attached to an electrical source.

Rip hurried back to where Kemp was at work. The private was using a
cutting nozzle that threw an almost invisible flame five feet long.
In air, the nozzle wouldn't have worked effectively beyond two feet, but
in space it cut right down to the end of the flame. Kemp had his arm
inside the hole and was peering past it as he finished the cut.

"Done, sir," he said, and adjusted the flame to a spout of red fire. He
thrust the torch into the hole and quickly withdrew it as pieces of
thorium flew out. A stream of water hosed into the tube would have worked
the same way.

Rip took a block of plutonium from Dominico and handed it to Kemp. "Cut
a plug and fit this into it. Then cut a second plug for the other piece.
They have to match perfectly, and you can't put them together to try out
the fit. If you do, we'll have fission right here in the open."

Kemp searched and found a piece he had cut in making the tube. It was
perfectly round, ideal for the purpose. He sliced off the inner side
where it tapered to a cone, then, working only by eye estimate, cut out a
hole in which the wedge of fission material would fit. He wasn't off by a
thirty-second of an inch. Skillful application of the torch melted the
thorium around the wedge and sealed it tightly.

Koa was ready with a sheet of nuclite. Trudeau arrived with a pole made
by lashing two crate sticks together.

Rip gave directions as they formed a cylinder of nuclite. Kemp
spot-welded it, and they pushed it into the hole.

Nunez found a small piece of material in one of the earlier craters. It
would provide some neutrons to start the chain reaction. Rip added it to
the front of the plutonium wedge, along with a piece of beryllium from
the