valanched once before," Troy commented. "Shall we
operate, Dr. Patterson?"

"Better extravagant with the taxpayers' money than sorry for
ourselves," Alec replied, pulling the avalanche gun from his holster.
It looked like an early-day Very pistol, with its big, straight-bore
muzzle. "Let's get back a couple of feet."

They kick-turned and skied back from the sides of the cornice. Alec
raised the gun and aimed at the center of the deepest segment over the
overhang. The gun discharged with a muffled "pop" and the concentrated
ball of plastic explosive arced through the air, visible to the naked
eye. It vanished into the snow roof and the men waited. Ten seconds
later there was a geyser of flame and the smoke and snow as the charge
detonated deep under the overhang. The wind whipped the cloud away and
the roof still held, despite the gaping hole.

"What do you think?" Troy asked.

"One more for good measure," Alec said as he fired again, this time to
the right of the first shot. The plastic detonated in another geyser
of smoke and snow, but the small cloud was instantly lost as the
entire overhang broke and fell the ten to twelve feet from the crest
to the face of the slope and then boiled and rolled, gathering more
snow and greater mass and impetus as it thundered down the slope and
was lost in the storm. The dense clouds of loose powder snow raised by
the avalanche whipped away in the clutches of the wind.

"Well done, Dr. Patterson," Troy called as he leaned into his poles
and moved out across the newly-crushed snow on the slope.

"Thank you, Dr. Braden," Alec called in his wake, "you may proceed to
the patient."

* * * * *

They worked past the buried radiation gauge to the crest and then
turned and came slowly back along the wind ridge, following directly
behind the detection needle. Troy glanced at his intensity gauge. The
needle was on the "danger" line in the red. He stopped. Behind him,
Alec checked his drop slowly down the windward side of the slope,
reading his own meter. When his intensity needle hit the same mark,
he, too, halted about thirty feet to Troy's right.

"I'm dead on," Troy said, indicating with a ski pole an imaginary line
straight ahead.

"I've got it about forty-five degrees left," Alec called, marking his
position and a direction line in the crust with a pole. Each moved
towards the other and from the mid-point of their two markings
extended with their