valley for a time and then dissipated."

Wayne frowned and shook his head. Both hypotheses made sense.

"Do you have any suggestions, Doctor?" Petersen said.

"Since we don't have any direct information about why those men died,
Colonel, I can't make any definite statements. But I can offer one bit
of advice to everyone: _wear your suits and be alert_."

* * * * *

During the week that followed, several groups went out without suffering
any ill effects. A short service was held for the eight of the _Mavis_
and then the skeletons were buried in the valley.

They ran a check on the double-nucleus beryllium toward the end of the
week, after it had been fairly safely established that no apparent harm
was going to come to them. Wayne and Sherri were both in the crew that
went outside to set up the detector.

"You man the detector plate," said Major MacDougal, who was in charge of
the group, turning to Wayne.

He put his hand on the plate and waited for the guide coordinates to be
set. MacDougal fumbled at the base of the detector for a moment, and the
machine began picking up eloptic radiations.

Wayne now looked down at the detector plate. "Here we are," he said.
"The dial's oscillating between four and eight, all right. The stuff's
here."

MacDougal whistled gently. "It's really sending, isn't it!" He pointed
toward the mountaintop. "From up there, too. It's going to be a nice
climb. Okay, pack the detector up and let's get back inside."

They entered the airlock and passed on into the ship.

"The D-N beryllium up there, sir," Major MacDougal said. "It's going to
be a devil of a job to get up to find the stuff."

"That's what Captain Wayne's here for," Petersen said. "Captain, what
do you think? Can you get up here?"

"It would have been easier to bring along a helicopter," Wayne said
wryly. "Pity the things don't fit into spaceships. But I think I can get
up there. I'd like to try surveying the lay of the land, first. I want
to know all the possible routes before I start climbing."

"Good idea," Petersen said. "I'll send you out with three men to do some
preliminary exploring. Boggs! Manetti! MacPherson! Suit up and get with
it!"

* * * * *

Wayne strode toward the spacesuit locker, took out his suit, and donned
it. Instead of the normal space boots, he put on the special
metamagnetic boots for mountain climbing. The little reactors in the