The column swung wide to the left, then back again. Off to the right was a circular depression perhaps fifty yards across; Bruce could not see the bottom. He paused, intending to question Sam; the Scoutmaster's voice prodded him. "Bruce! Keep moving!"

Much later Speedy's voice called out, "Hard ground!" Shortly the column reached it and stopped to remove skis. Bruce switched off his radio and touched his helmet to Sam's.

"What was that back where the Skipper yelled at me?"

"That? That was a morning glory. They're poison!"

"A 'morning glory'?"

"Sort of a sink hole. If you get on the slope, you never get out. Crumbles out from under you and you wind up buried in the bottom. There you stay - until your air gives out. Lot of prospectors die that way. They go out alone and are likely to come back in the dark."

"How do you know what happens if they go out alone?"

"Suppose you saw tracks leading up to one and no tracks going away?"

"Oh!" Bruce felt silly.

The troop swung into a lope; slowly the hills drew closer and loomed high into the sky. Mr. Andrews called a halt. "Camp," he said. "Sam, spot the shelter west of that outcropping. Bruce, watch what Sam does.

The shelter was an airtight tent, framed by a half cylinder of woven heavy wire. The frame came in sections. The Scoutmaster's huge pack was the air bag.

The skeleton was erected over a ground frame, anchored at corners and over which was spread an asbestos pad. The curved roof and wall sections followed. Sam tested joints with a wrench, then ordered the air bag unrolled. The air lock, a steel drum, was locked into the frame and gasketed to the bag. Meanwhile, two Scouts were rigging a Sun shade.

Five boys crawled inside and stood up, arms stretched high. The others passed in all the duffel except skis and poles. Mr. Andrews was last in and closed the air lock. The metal frame blocked radio communication; Sam plugged a phone connection from the lock to his helmet. "Testing," he said.

Bruce could hear the answer, relayed through Sam's radio. "Ready to inflate."

"Okay." The bag surged up, filling the frame. Sam said, "You go on, Bruce. There's nothing left but to adjust the shade."

"I'd better watch."

"Okay." The shade was a flimsy Venetian blind, stretched over the shelter. Sam half - opened the slats. "It's cold inside," he commented, "from expanding gas. But it warms up fast." Presently, coached by phone, he closed them a bit. "Go inside," he urged Bruce. "It may be half an hour before I get the temperature steady."

"Maybe I should," admitted Bruce. "I feel dizzy."

Sam studied him. "Too hot?"

"Yeah, I guess so."

"You've held still in the Sun too long. Doesn't give the air a chance to circulate. Here." Sam opened Bruce's supply valve wider; "Go inside."

Gratefully, Bruce complied.

As he backed in, and straightened up, two boys grabbed him. They closed his valves, unlocked his helmet, and peeled off his suit. The suit traveled from hand to hand and was racked. Bruce looked around.

Day lamps were strung from air lock to a curtain at the far end that shut off the sanitary unit. Near this curtain suits and helmets were racked. Scouts were lounging on both sides of the long room. Near the entrance a Scout was on watch at the air conditioner, a blood - oxygen indicator clipped to his ear. Nearby, Mr. Andrews phoned temperature changes to Sam. In the middle of the room Chubby had set up his commissary. He waved. "Hi, Bruce! Siddown - chow in two shakes."

Two Scouts made room for Bruce and he sat. One of them said, "Y'ever been at Yale?" Bruce had not. "That's where I'm going," the Scout confided. "My brother's there now." Bruce began to feel at home.

When Sam came in Chubby served chow, beef stew, steaming and fragrant, packaged rolls, and bricks of peach ice cream. Bruce decided that Moon Scouts had it soft. After supper, the Bugler got out his harmonica and played. Bruce leaned back, feeling pleasantly drowsy.

"Hollifield!" Bruce snapped awake. "Let's try you on first aid."

For thirty minutes Bruce demonstrated air tourniquets and emergency suit patches, artificial respiration for a man in a space suit, what to do for Sun stroke, for anoxia, for fractures. "That'll do," the Scoutmaster concluded. "One thing: What do you do if a man cracks his helmet?"

Bruce was puzzled. "Why," he blurted, "you bury him."

"Check," the Scoutmaster agreed. "So be careful. Okay, sports - six hours of sleep. Sam, set the watch."

Sam assigned six boys, including himself. Bruce asked, "Shouldn't I take a watch?"

Mr. Andrews intervened. "No. And take yourself off, Sam. You'll take Bruce on his two - man hike tomorrow; you'll need your sleep."

"Okay, Skipper." He added to Bruce, "There's nothing to it. I'll show you." The Scout on duty watched several instruments, but, as with suits, the important one was the blood - oxygen reading. Stale air was passed through a calcium oxide bath, which precipitated carbon dioxide as calcium carbonate. The purified air continued through dry sodium hydroxide, removing water vapor.

"The kid on watch makes sure the oxygen replacement is okay," Sam went on. "If anything went wrong, he'd wake us and we'd scramble into suits."

Mr. Andrews shooed them to bed. By the time Bruce had taken his turn at the sanitary unit and found a place to lie down, the harmonica was sobbing: "Day is done Gone the Sun..."

It seemed odd to hear Taps when the Sun was still overhead. They couldn't wait a week for sundown, of course. These colonials kept funny hours... bed at what amounted to early evening, up at one in the morning. He'd ask Sam. Sam wasn't a bad guy - a little bit know - it - all. Odd to sleep on a bare floor, too - not that it mattered with low gravity. He was still pondering it when his ears were assaulted by Reveille, played on the harmonica.

Breakfast was scrambled eggs, cooked on the spot. Camp was struck, and the troop was moving in less than an hour. They headed for Base Camp at a lope.

The way wound through passes, skirted craters. They had covered thirty miles and Bruce was getting hungry when the pathfinder called, "Heel and toe!" They converged on an air lock, set in a hillside.

Base Camp had not the slick finish of Luna City, being rough caverns sealed to air tightness, but each troop had its own well - equipped troop room. Air was renewed by hydroponic garden, like Luna City; there was a Sun power plant and accumulators to last through the long, cold nights.

Bruce hurried through lunch; he was eager to start his two - man hike. They outfitted as before, except that reserve air and water replaced packaged grub. Sam fitted a spring - fed clip of hiking rations into the collar of Bruce's suit.

The Scoutmaster inspected them at the lock. "Where to, Sam?"

"We'll head southeast. I'll blaze it."

"Hmm - rough country. Well, back by midnight, and stay out of caves."

"Yes, sir."

Outside Sam sighed, "Whew! I thought he was going to say not to climb."

"We're going to?"

"Sure. You can, can't you?"

"Got my Alpine badge."

"I'll do the hard part, anyhow. Let's go."

Sam led out of the hills and across a baked plain. He hit an eight - mile gait, increased it to a twelve - miler. Bruce swung along, enjoying it. "Swell of you to do this, Sam."

"Nuts. If I weren't here, I'd be helping to seal the gymnasium."

"Just the same, I need this hike for my Mooncraft badge."

Sam let several strides pass. "Look, Bruce - you don't really expect to make Lunar Eagle?"

"Why not? I've got my optional badges. There are only four required ones that are terribly different: camping, Mooncraft, path finding, and pioneering. I've studied like the dickens and now I'm getting experience.

"I don't doubt you've studied. But the Review Board are tough eggs. You've got to be a real Moon hand to get by."