"I can walk through walls!"

"Rubbish!"

"Yeah, pull the other one!"

Brain was always coming up with stupid comments. We always let him know what we thought when he did though. He always took it in good part too. He was a likable idiot.

"No really, guys. Its possible to walk through anything !"

"You need your head examined!"

Brain pushed his large, black-rimmed glasses up his nose and looked at us earnestly.

"If you had been listening in class . . .," he said, "You would have heard all that stuff about atoms."

"No such thing!" we said, 'Too small to see! If you can't see'um they're not real! Just a fairy tale!"

"Yeah, a fairy tale!"

Brain (that was his nickname) tilted his glasses up his nose again and frowned at us.

"You guys are going to miss out one day. Science is moving ahead and you will still be in the Dark Ages."

"OK! OK!" we laughed, slapping him on the back, "Give us your theory!"

"Well its not really a theory" said Brains, "Its been proven. Atoms are more space than solid. They attract each other when they're apart, and they repel each other when they get too close .. ."

"Sound like girls!" I said, "First they give you the come on, then they dump you!"

"Cut the jokes for a minute, will you?" said Brain "I'm trying to be serious. Look, if we could find a way of stopping that repelling force, we could pass objects through each other, no trouble at all!. It's already sort of happening in Nature, only it takes longer."

"What are you talking about?" we laughed.

"Where in Nature?" we said.

"In the rocks," said Brain "I've seen a picture of two types of rock stuck together. They've been squashed so hard against each other, they've started to move through