I almost dropped it.

"It's like a ball of ice!" I said. "Have you been keeping it in the

refrigerator?"

"No. As a matter of fact, it was at room temperature a few minutes

ago."

"Now wait a minute," I said. "I only teach physics in high school, but

I know better than that. Moving around in warm air doesn't make

anything cold except by evaporation."

"Well, there's your input and output, John," he said. "The ball lost

heat and took on motion. Simple conversion."

My jaw must have dropped to my waist. "Do you mean that that little

thing is converting heat to kinetic energy?"

"Apparently."

"But that's impossible!"

He was beginning to smile thoughtfully. The ball was not as cold now

as it had been and I was holding it in my lap.

"A steam engine does it," he said, "and a steam turbine. Of course,

they're not very efficient."

"They work mechanically, too, and only because water expands when it

turns to steam."

"This seems to do it differently," he said, sipping thoughtfully at

his dark-brown martini. "I don't know exactly how--maybe something

piezo-electric about the way its molecules slide about. I ran some

tests--measured its impact energy in foot pounds and compared that

with the heat loss in BTUs. Seemed to be about 98 per cent efficient,

as close as I could tell. Apparently it converts heat into bounce very

well. Interesting, isn't it?"

"_Interesting?_" I almost came flying out of my chair. My mind was

beginning to spin like crazy. "If you're not pulling my leg with this

thing, Farnsworth, you've got something by the tail there that's just

a little bit bigger than the discovery of fire."

He blushed modestly. "I'd rather thought that myself," he admitted.

"Good Lord, look at the heat that's available!" I said, getting really

excited now.

* * * * *

Farnsworth was still smiling, very pleased with himself. "I suppose

you could put this thing in a box, with convection fins, and let it

bounce around inside--"

"I'm way ahead of you," I said. "But that wouldn't work. All your

kinetic energy would go right back to heat, on impact--and eventually

that little ball would build up enough speed to blast its way through

any box you could build."

"Then how would you work it?"

"Well," I said, choking down the rest of my rum, "you'd seal the ball

in a big steel cylinder, attach the cylinder to a crankshaft and

flywheel, give the thing a shake to start the ball bouncing back and

forth, and let it run like a gasoline engine or something. It would

get all the heat it needed from the air in a normal room. Mount the

apparatus in your house and it would pump your water, operate a

generator and keep you cool at the same time!"

The Big Bounce · 第 5 / 7 题