"Oh, forget it, Gus. Have a drink."
"A pious thought — but not Scotch. I'm going to have a martini; we ought to eat pretty soon."
"I'll have one, too."
"Do you good." Erickson lifted his blond head and bellowed, "Israfel!"
A large, black person appeared at his elbow. "Mistuh Erickson! Yes, suh!"
"Izzy, fetch two martinis. Make mine with Italian." He turned back to Harper. "What are you going to do now, Cal?"
"Radiation laboratory."
"Well, that's not so bad. I'd like to have a go at the matter of rocket fuels myself. I've got some ideas."
Harper looked mildly amused. "You mean atomic fuel for interplanetary flight? The problem's pretty well exhausted. No, son, the stratosphere is the ceiling until we think up something better than rockets. Of course, you could mount the bomb in a ship, and figure out some jury rig to convert its radiant output into push, but where does that get you? One bomb, one ship — and twenty years of mining in Little America has only produced enough pitchblende to make one bomb. That's disregarding the question of getting the company to lend you their one bomb for anything that doesn't pay dividends."
Erickson looked balky. "I don't concede that you've covered all the alternatives. What have we got? The early rocket boys went right ahead trying to build better rockets, serene in the belief that, by the time they could build rockets good enough to fly to the Moon, a fuel would be perfected that would do the trick. And they did build ships that were good enough — you could take any ship that makes the antipodes run, and refit it for the Moon— if you had a fuel that was sufficiently concentrated to maintain the necessary push for the whole run. But they haven't got it.