"I meant those damned, long, shining objects that shoot that light-ray of theirs. Their guns shoot it out in packages, but we can understand that and deal with them; our artillery is just as good. But if we can't stop those shining things there will be no army left and that means no men left on this planet. This army is our last resource. If you know of anything, anything, that will stop them, for God's sake tell us! All we've found that does any good so far are the twelve-inch railroad guns and we have only four of them. One was knocked out by their shells this afternoon."
"You mean their fighting-machines," Sherman replied. "Why, I'm not absolutely certain. I only know what I picked up from them and what Marta Lami"—he swallowed hard at the mention of her name—"the bravest woman in the world, told me. But I think that a shell with a lead cap would go through those fighting machines like a knife through a piece of cheese."
There was a tiny silence in the room at this momentous announcement. Then an artillery officer said, dreamily, "The armor-piercing shells the railroad guns use have lead caps."
As though his words had released a spell there came a quick drumfire of questions:
"What are they armored with?"
"What kind of a power-plant do they use?"
"Can you stop the light-ray?"
"What makes you think so?"
Sherman smiled. "Just a moment. One question at a time. I'm not sure I can answer them all, anyway. As to what makes me think so and what they're armored with, they have a coating of steel armor, but it isn't very thick. It's plated on the outside with a coat of lead and outside that with the substance they call 'pure light.' I don't know what it is, but it's the same stuff they use in the light-ray and in their shells, and I know that lead sheeting will stop it, even when the lead is very thin."