How do you equip an army of barbarians still in the early Iron Age to cross four and a third light-years of space?
A preliminary question, perhaps is, Do you want to?
Ray emphatically didn't, but he had very little choice in the matter. He was soon given forcibly to understand that men kept their place and did as they were commanded.
He went to Urushkidan and poured out his sorrows. The Martian, after an abortive attempt to steal the spaceship and sneak home, had been given a room in one of the castle towers and was covering large sheets of local parchment with equations. This place, thought Ray, has octopuses in the belfry.
"They want to go to Jupiter and fight the Jovians," he said.
"What of it?" asked Urushkidan, lighting his pipe. He had found that dried bark could be smoked. "Tey may eben succeed. Primitibes habe often obercome more adbanced and better armed hosts. Read te history of Eart sometime."
"But they'll take us along."
"Oh. Oh-oh! Tat is different." The Martian riffled through his papers. "Let me see, I tink Equations 549 trough 627 indicate—yes, here we are. It is possible to project te same type of dribing beam as we use in te faster-tan-light engine so as to impart a desired belocity bector to external objects. Toward or away from you. Or—look here, differentiation of tis equation shows it would be equally simple to break intranuclear bonds by trowing only a certain type of particle into te pseudo-condition. Te atom would ten feed on its own energy."
Ray looked at him in awe. "You," he whispered, "have just invented the tractor beam, the pressor beam, the disintegrator, and the all-purpose, all-fuel atomic motor."