"Weighty! I guess you're right, Mike."

"I know I'm right!" said Mike. "If you spent six weeks in bed you'd
expect to feel wobbly when you tried to walk. Up on the Platform you
didn't even use energy to stand up! We didn't realize it, but we were
living like invalids! We'll get our strength back, but next time we'll
take measures. Huh! Take a trip to Mars in free fall, and by the time a
guy got there his muscles'd be so flabby he couldn't stand up in
half-gravity! Something's got to be done about that, Joe!"

Joe said sombrely, "Something's got to be done about space ships before
that comes up again!"

Somebody appeared with a tray. There was food on it. Smoking hot food.
Joe looked at it and knew that his appetite, anyhow, was back to Earth
normal.

"Thanks!" he mumbled appreciatively, and attacked the food.

Mike drank his coffee. Then he said, "Joe, do you know anything about
powder metallurgy?"

Joe shrugged. It hurt. "Powder metallurgy? Yes, I've seen it used, at my
father's plant. They've made small precision parts with it. Why?"

"D'you know if anybody ever made a weld with it?" asked Mike.

Joe chewed. Then he said: