ked field amid the
rousing cheers from the stands. Across the field, the cadets of the
_Arcturus_ unit walked out to meet them, stopping beside McKenny at the
mid-field line. Mike waited for the six boys to form a circle around
him, while he held the mercuryball, a twelve-inch plastic sphere, filled
with air and the tricky tube of mercury.

"You all know the rules," announced McKenny abruptly. "Head, shoulders,
feet, knees, or any part of your body except your hands, can touch the
ball. _Polaris_ unit will defend the north goal," he said, pointing to a
white chalk line fifty yards away, "_Arcturus_ the south," and he
pointed to a line equally distant in the opposite direction.
"Five-minute periods, with one-minute rest between. All clear?"

As captain of the _Polaris_ unit, Tom nodded, while smiling at the
captain of the _Arcturus_ team, a tow-headed boy with short chunky legs
named Schohari.

"All clear, Mike," said Tom.

"All clear here, Mike," responded Schohari.

"All right, shake hands and take your places."

The six boys shook hands and jogged toward respective opposite lines.
Mike waited for them to reach their goal lines, and then placed the ball
in the middle of a chalk-drawn circle.

Toeing the line, Tom, Roger and Astro eyed the _Arcturus_ crew and
prepared for the dash to the ball.

"All right, fellas," urged Tom, "let's show them something!"

"Yeah," breathed Astro, "just let me get my size thirteens on that
pumpkin before it starts twisting around!"

Astro wanted the advantage of the first kick at the ball while the
mercury tube inside was still quiet. Once the mercury was agitated, the
ball would be as easy to kick as a well-greased eel.

"We'll block for you, Astro," said Tom, "and you put every ounce of
beef you've got into that first kick. If we're lucky, we might be able
to get the jump on them!"

"Cut the chatter," snapped Roger nervously. "Baldy's ready to give us
the go ahead!"

Standing on the side lines, Warrant Officer McKenny slowly raised his
hand, and the crowd in the grandstand hushed in eager anticipation. A
second passed and then there was a tremendous roar as he brought his
hand down and blew heavily on the whistle.

Running as if their lives depended on it, the six cadets of the two
units raced headlong toward the ball. Tom, just a little faster than
Roger or Astro, flashed down the field and veered off to block the
advancing Schohari. Roger, following him, charged into