"I mean, sir, that we dare not call any ship to our assistance while these things exist. I have found no way of destroying them. If we lead them back to Mars, and they prove indestructible, we would doom the system. They would be carried to every planet. And the planets themselves are food for them." "Mightn't other physicists succeed where you fail, Markoe?" asked Chapman, with a sneer. "Maybe you're not as good as you think! We have plenty of brilliant men in the labs and universities. They'd probably lick these spaceworms in no time." "There are many men more brilliant than myself," replied Markoe, ignoring the sneer. "And if they can be destroyed those men would find the way. But it would take time. Time! I am not in error about that, Mr. Chapman. Barring a lucky accident it would take months of experiment. Think of the loss of life that would precede their success! And it's fully possible that they are indestructible. Lord, man! Will you gamble the fate of our whole civilization just to save your own skin? These flames are of disease of metal--maybe a disease of planets. By our oath, we must find the cure--or not return!" "Damned nonsense!" broke in Simms. "To hell with that stuff! Why haven't these flames attacked the planets before, if they're all you say? And if they've just come into the system we can't stop them. They're probably on the planets already. What good will our death do? I don't have to be a physicist to see that these things can live in space. They don't need heat or air. They can go where they like--" "That's where you're wrong, Mr. Simms," interrupted Markoe. "They can't go where they like. It's true they need no atmosphere. But they do need _food_! They can move through empty space only relatively short distances; the force which holds them together consumes tremendous quantities of energy. When the _Denebola_ is gone they will break up, die, if you want to call it that, unless an asteroid or meteor is within their reach. And they aren't new to the system, in my opinion. I suppose they're as old on the asteroids as life is on Earth; older, maybe, but they can't cross the enormous gulf between the asteroid belt and the nearest planets, Mars and Jupiter." "You're space crazy!" retorted Simms. "Why, in that length of time they'd have reduced a quarter of matter a thousand times as great as all the asteroids--" "You forget the distances between the asteroids themselves. The normal 'death-rate' of the earthworms of space on the asteroids must be very high. And their consumption of stone and ore is much slower; I've timed them on samples we collected." * * * * *