"Not long," admitted Walt.
"A gun is an overloaded machine," said Don. "Even a little one. The life of a gun barrel is measured in seconds; totalling up the time of transit of all the rounds from new gun to worn barrel gives a figure expressed in seconds. Your electron gun, Walt, whether it be fish, flesh, or fowl, must be overloaded for an instant."
"Is overload a necessary requirement?" asked Arden. "It seems to me that you might be able to bore a sixteen-inch gun for a twenty-two. What now, little man?"
"By the time we get something big enough to do more than knock paint off, we'll have something bigger than a twenty-two," grinned Channing. "I was speaking in terms of available strength versus required punch. In the way that a girder will hold tremendous overloads for brief instants, a gun is overloaded for milliseconds. We'll have a problem—"
"O.K., aside from that, have you figured out why I haven't been able to do more than warm anything larger than a house brick?"
"Sure," laughed Channing. "What happens in a multi-grid radio tube when the suppressor grid is hanging free?"
"Charges negative and blocks the electron stream ... hey! That's it!"
"What?" asked Arden.
"Sure," said Walt. "We fire off a batch of electrons, and the first contingent that arrives charges the affair so that the rest of the beam sort of wriggles out of line."
"Your meteor is going to take on a charge of phenomenal negative value, and the rest of your beam is going to be deflected away, just as your electron lenses deflect the original beam," said Channing. "And now another thing, old turnip. You're squirting out a lot of electrons. That's much amperage. Your voltage—velocity—is nothing to rave about even though it sounds high. Watts is what you want, to corn a phrase."